<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="rfc2629.xslt" ?> <!-- generated by https://github.com/cabo/kramdown-rfc2629 version 1.6.2 (Ruby 2.7.0) --><!DOCTYPE rfc [ <!ENTITY nbsp " "> <!ENTITY zwsp "​"> <!ENTITY nbhy "‑"> <!ENTITY wj "⁠"> ]><?rfc strict="yes"?> <?rfc compact="yes"?><!-- generated by https://github.com/cabo/kramdown-rfc2629 version 1.6.2 (Ruby 2.7.0) --> <rfc xmlns:xi="http://www.w3.org/2001/XInclude" ipr="trust200902" docName="draft-ietf-lpwan-schc-yang-data-model-21" number="9363" submissionType="IETF" category="std" consensus="true" tocInclude="true" sortRefs="true"symRefs="true">symRefs="true" updates="" obsoletes="" xml:lang="en" version="3"> <!-- xml2rfc v2v3 conversion 3.15.0 --> <front> <title abbrev="LPWAN SCHC YANGmodule">DataData Model">A YANG Data Model for Static Context Header Compression (SCHC)</title> <seriesInfo name="RFC" value="9363"/> <author initials="A." surname="Minaburo" fullname="Ana Minaburo"> <organization>Acklio</organization> <address> <postal> <street>1137A avenue des Champs Blancs</street><city>35510 Cesson-Sevigne<city>Cesson-Sevigne Cedex</city> <code>35510</code> <country>France</country> </postal> <email>ana@ackl.io</email> </address> </author> <author initials="L." surname="Toutain" fullname="Laurent Toutain"><organization>Institut<organization abbrev="IMT Atlantique">Institut MINES TELECOM; IMT Atlantique</organization> <address> <postal> <street>2 rue de laChataigneraie</street> <street>CSChataigneraie CS 17607</street><city>35576 Cesson-Sevigne<city>Cesson-Sevigne Cedex</city> <code>35576</code> <country>France</country> </postal> <email>Laurent.Toutain@imt-atlantique.fr</email> </address> </author> <dateyear="2022" month="October" day="09"/> <workgroup>lpwan Working Group</workgroup>year="2023" month="February"/> <area>int</area> <workgroup>lpwan</workgroup> <keyword>Header Compression</keyword> <keyword>Fragmentation</keyword> <keyword>SCHC Rule</keyword> <keyword>IPv6</keyword> <keyword>UDP</keyword> <keyword>CoAP</keyword> <keyword>OSCORE</keyword> <abstract> <t>This document describes a YANG data model for theSCHC (StaticStatic Context HeaderCompression)Compression (SCHC) compression and fragmentationrules.</t>Rules.</t> <t>This document formalizes the description of therulesRules for better interoperability between SCHC instances either to exchange a set ofrulesRules or to modify the parameters of somerules parameters.</t>Rules.</t> </abstract> </front> <middle> <sectionanchor="Introduction"><name>Introduction</name>anchor="Introduction"> <name>Introduction</name> <t>SCHC is a compression and fragmentation mechanism for constrained networks defined in <xref target="RFC8724"/>. It is based on a static context shared by two entities at the boundary of the constrained network. <xref target="RFC8724"/> provides an informal representation of therulesRules used either for compression/decompression(or C/D)(C/D) or fragmentation/reassembly(or F/R).(F/R). The goal of this document is to formalize the description of therulesRules to offer:</t><t><list style="symbols"> <t>the<ul spacing="normal"> <li>the same definition on both ends, even if the internal representation isdifferent;</t> <t>andifferent, and</li> <li>an update of the other end to set up some specific values(e.g.(e.g., IPv6 prefix, destinationaddress,...).</t> </list></t>address, etc.).</li> </ul> <t><xref target="I-D.ietf-lpwan-architecture"/> illustrates the exchange ofrulesRules using the YANG data model.</t> <t>This document defines a YANGmoduledata model <xref target="RFC7950"/> to represent both compression and fragmentationrules,Rules, which leads to common representation for values for all therulesRules' elements.</t> </section> <sectionanchor="requirements-language"><name>Requirementsanchor="requirements-language"> <name>Requirements Language</name><t>The<t> The key words"MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY","<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>", "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>", "<bcp14>MAY</bcp14>", and"OPTIONAL""<bcp14>OPTIONAL</bcp14>" in this document are to be interpreted as described inBCP 14BCP 14 <xref target="RFC2119"/> <xref target="RFC8174"/> when, and only when, they appear in all capitals, as shownhere.</t>here. </t> </section> <sectionanchor="Term"><name>Terminology</name>anchor="Term"> <name>Terminology</name> <t>This section defines the terminology and acronyms used in this document. It extends the terminology of <xref target="RFC8376"/>.</t><t><list style="symbols"> <t>App: LPWAN<dl newline="false" spacing="normal"> <dt>App:</dt> <dd>Low-Power WAN (LPWAN) Application, as defined by <xref target="RFC8376"/>. An application sending/receiving packets to/from theDev.</t> <t>Bi: Bidirectional.Dev.</dd> <dt>Bi:</dt> <dd>Bidirectional. Characterizes a Field Descriptor that applies to headers of packets traveling in either direction (Up andDw,Dw; see thisglossary).</t> <t>CDA: Compression/Decompressionglossary).</dd> <dt>CDA:</dt> <dd>Compression/Decompression Action. Describes the pair of actions that are performed at the compressor to compress a header field and at the decompressor to recover the original value of the headerfield.</t> <t>Context: Afield.</dd> <dt>Context:</dt> <dd>A set of Rules used to compress/decompressheaders.</t> <t>Dev: Device,headers.</dd> <dt>Dev:</dt> <dd>Device, as defined by <xreftarget="RFC8376"/>.</t> <t>DevIID: Devicetarget="RFC8376"/>.</dd> <dt>DevIID:</dt> <dd>Device Interface Identifier. The IID that identifies the Devinterface.</t> <t>DI: Directioninterface.</dd> <dt>DI:</dt> <dd>Direction Indicator. This field tells which direction of packet travel (Up,DwDw, or Bi) a FieldDescriptionDescriptor applies to. This allows for asymmetric processing, using the sameRule.</t> <t>Dw: DownlinkRule.</dd> <dt>Dw:</dt> <dd>Downlink direction for compression/decompression, from SCHC C/D in the network to SCHC C/D in theDev.</t> <t>FID:Dev.</dd> <dt>FID:</dt> <dd>Field Identifier or FieldIdentifier.ID. This identifies the protocol and field a FieldDescriptionDescriptor appliesto.</t> <t>FL: Field Lengthto.</dd> <dt>FL:</dt> <dd>Field Length. This is the length of the original packet header field. It is expressed as a number of bits for header fields of fixed lengths or as a type (e.g., variable, token length, ...) forfield lengthsField Lengths that are unknown at the time of Rule creation. The length of a header field is defined in the corresponding protocol specification (such as IPv6 orUDP).</t> <t>FP: whenUDP).</dd> <dt>FP:</dt> <dd>Field Position. When aFieldfield is expected to appear multiple times in a header, the Field Position specifies the occurrence this FieldDescriptionDescriptor applies to (for example, firsturi-pathUri-Path option, seconduri-path,Uri-Path, etc. in aCoAPConstrained Application Protocol (CoAP) header), counting from 1. The value 0 is special and means "don'tcare", seecare" (see <xreftarget="RFC8724"/> Section 7.2.</t> <t>IID: Interfacetarget="RFC8724" sectionFormat="of" section="7.2"/>).</dd> <dt>IID:</dt> <dd>Interface Identifier. See the IPv6 addressing architecture <xreftarget="RFC7136"/>.</t> <t>L2 Word: thistarget="RFC7136"/>.</dd> <dt>L2 Word:</dt> <dd>This is the minimum subdivision of payload data that theL2Layer 2 (L2) will carry. In most L2 technologies, the L2 Word is an octet. In bit-oriented radio technologies, the L2 Word might be a single bit. The L2 Word size is assumed to be constant over time for eachdevice.</t> <t>MO: Matchingdevice.</dd> <dt>MO:</dt> <dd>Matching Operator. An operator used to match a value contained in a header field with a value contained in aRule.</t> <t>Rule ID (Rule Identifier):Rule.</dd> <dt>RuleID:</dt> <dd>Rule Identifier. An identifier for a Rule. SCHC C/D on both sides share the sameRule IDRuleID for a given packet. A set ofRule IDsRuleIDs are used to support SCHC F/Rfunctionality.</t> <t>TV: Target value.functionality.</dd> <dt>TV:</dt> <dd>Target Value. A value contained in a Rule that will be matched with the value of a headerfield.</t> <t>Up: Uplinkfield.</dd> <dt>Up:</dt> <dd>Uplink direction for compression/decompression, from the Dev SCHC C/D to the network SCHCC/D.</t> </list></t>C/D.</dd> </dl> </section> <sectionanchor="schc-rules"><name>SCHC rules</name>anchor="schc-rules"> <name>SCHC Rules</name> <t>SCHC compression isgeneric,generic; the main mechanism does not refer to a specific protocol. Any header field is abstracted throughana Field Identifier (FID), a position (FP), a direction (DI), and a value that can be a numerical value or a string. <xref target="RFC8724"/> and <xref target="RFC8824"/> specify fields for IPv6 <xref target="RFC8200"/>,UDP<xrefUDP <xref target="RFC0768"/>, and CoAP <xreftarget="RFC7252"/>target="RFC7252"/>, including options defined for no server response <xref target="RFC7967"/> andOSCOREObject Security for Constrained RESTful Environments (OSCORE) <xref target="RFC8613"/>. For thelatterlatter, <xref target="RFC8824"/> splits this field intosub-fields.</t>subfields.</t> <t>SCHC fragmentation requires a set of common parameters that are included in arule.Rule. These parameters are defined in <xref target="RFC8724"/>.</t> <t>The YANG data model enables the compression and the fragmentation selection using the feature statement.</t> <sectionanchor="comp_types"><name>Compressionanchor="comp_types"> <name>Compression Rules</name> <t><xref target="RFC8724"/> proposes an informal representation of the compressionrule.Rule. A compression context for a device is composed of a set ofrules.Rules. EachruleRule contains information to describe a specific field in the header to be compressed.</t> <figuretitle="Compressionanchor="Fig-ctxt"> <name>Compression DecompressionContext" anchor="Fig-ctxt"><artwork><![CDATA[Context</name> <artwork><![CDATA[ +-----------------------------------------------------------------+ | Rule N | +-----------------------------------------------------------------+| | Rule i || +-----------------------------------------------------------------+|| | (FID) Rule 1 ||| |+-------+--+--+--+------------+-----------------+---------------+||| ||Field 1|FL|FP|DI|Target Value|Matching Operator|Comp/Decomp Act|||| |+-------+--+--+--+------------+-----------------+---------------+||| ||Field 2|FL|FP|DI|Target Value|Matching Operator|Comp/Decomp Act|||| |+-------+--+--+--+------------+-----------------+---------------+||| ||... |..|..|..| ... | ... | ... |||| |+-------+--+--+--+------------+-----------------+---------------+||/ ||Field N|FL|FP|DI|Target Value|Matching Operator|Comp/Decomp Act||| |+-------+--+--+--+------------+-----------------+---------------+|/ | | \-----------------------------------------------------------------/]]></artwork></figure>]]></artwork> </figure> </section> <sectionanchor="identifier-generation"><name>Identifier generation</name>anchor="identifier-generation"> <name>Identifier Generation</name> <t>Identifiers used in the SCHC YANG data model are from the identityref statement to ensure global uniqueness and easy augmentation if needed. The principle to define a new type based on a group of identityref is the following:</t><t><list style="symbols"> <t>define<ul spacing="normal"> <li>Define a main identity ending with the keywordbase-type.</t> <t>derivebase-type.</li> <li>Derive all the identities used in theData Modeldata model from this basetype.</t> <t>createtype.</li> <li>Create a typedef from this basetype.</t> </list></t>type.</li> </ul> <t>The example below (<xref target="Fig-identityref"/>) shows how an identityref is created forRCS (ReassemblyReassembly CheckSequence)Sequence (RCS) algorithms used during SCHC fragmentation.</t> <figuretitle="Principleanchor="Fig-identityref"> <name>Principle todefineDefine atype basedType Based onidentityref." anchor="Fig-identityref"><artwork><![CDATA[identityref</name> <sourcecode type=""><![CDATA[ identity rcs-algorithm-base-type { description "Identify which algorithm is used to compute RCS. The algorithm also defines the size of the RCS field."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } identity rcs-crc32 { base rcs-algorithm-base-type; description"CRC 32"CRC32 defined as default RCS inRFC8724.RFC 8724. This RCS is 4 bytes long."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } typedef rcs-algorithm-type { type identityref { base rcs-algorithm-base-type; } description "Define the type for RCS algorithm inrules.";Rules."; }]]></artwork></figure>]]></sourcecode> </figure> </section> <sectionanchor="convention-for-field-identifier"><name>Conventionanchor="convention-for-field-identifier"> <name>Convention for Field Identifier</name> <t>In the process of compression, the headers of the original packet are first parsed to create a list of fields. This list of fields is matched against therulesRules to find the appropriateruleRule and apply compression. <xref target="RFC8724"/> does not state how thefieldField ID value is constructed. In examples, identification is done through a string indexed by the protocol name(e.g.(e.g., IPv6.version,CoAP.version,...).</t>CoAP.version, etc.).</t> <t>The current YANG data model includesfieldsfield definitions found in <xreftarget="RFC8724"/>,target="RFC8724"/> and <xref target="RFC8824"/>.</t> <t>Using the YANG data model, each fieldMUST<bcp14>MUST</bcp14> be identified through a global YANGidentityref.<br /> Aidentityref.</t> <t>A YANGfieldField ID for the protocol is always derived from the fid-base-type.ThenThen, an identity for each protocol is specified using the naming convention fid-<<protocol name>>-base-type. All possible fields for this protocolMUST<bcp14>MUST</bcp14> derive from the protocol identity. The naming convention is "fid-" followed by the protocol name and the field name. If a field has to be divided intosub-fields,subfields, the field identity serves as a base.</t> <t>The full field-id definition is found in <xref target="annexA"/>. A type is defined for the IPv6 protocol, and each field is based on it. Note that theDiffServDiffserv bits derive from the Traffic Class identity.</t> </section> <sectionanchor="convention-for-field-length"><name>Conventionanchor="convention-for-field-length"> <name>Convention for Fieldlength</name> <t>Field lengthLength</name> <t>The Field Length is either an integer giving the size of a field in bits or a specific function. <xref target="RFC8724"/> defines the "var"functionfunction, which allowsvariable lengthvariable-length fields (whose length is expressed inbytes)bytes), and <xref target="RFC8824"/> defines the "tkl" function for managing the CoAP TokenlengthLength field.</t> <t>The naming convention is "fl-" followed by the function name.</t> <t>Thefield lengthField Length function can be defined as anidentityrefidentityref, as described in <xref target="annexA"/>. Therefore, the type forfield lengththe Field Length is a union between an integer giving the size of the length in bits and the identityref.</t> </section> <sectionanchor="convention-for-field-position"><name>Conventionanchor="convention-for-field-position"> <name>Convention for Fieldposition</name> <t>Field positionPosition</name> <t>The Field Position is a positive integerwhichthat gives the occurrence times of a specific field from the header start. The default value is1,1 and is incremented at each repetition. Value 0 indicates that the position is not important and is not considered during theruleRule selection process.</t><t>Field position<t>The Field Position is a positive integer. The type is uint8.</t> </section> <sectionanchor="convention-for-direction-indicator"><name>Conventionanchor="convention-for-direction-indicator"> <name>Convention for Direction Indicator</name> <t>The Direction Indicator(di)is used to tell if a field appears in both directions (Bi) or only uplink (Up) or Downlink (Dw). The naming convention is "di" followed by the Direction Indicator name.</t> <t>The type is "di-type".</t> </section> <sectionanchor="target_value"><name>Conventionanchor="target_value"> <name>Convention for Target Value</name> <t>The Target Value is a list of binary sequences of any length, aligned to the left. In therule,Rule, the structure will be used as a list, with the index as a key. The highest index value is used to compute the size of the index sent in residue for the match-mappingCDA (CompressionCompression DecompressionAction).Action (CDA). The index can specify several values:</t><t><list style="symbols"> <t>For Equal<ul spacing="normal"> <li>For equal andMSB,most significant bits (MSBs), the Target Value contains a single element. Therefore, the index is set to0.</t> <t>For0.</li> <li>For match-mapping, the Target Value can contain several elements. Index valuesMUST<bcp14>MUST</bcp14> start from 0 andMUST<bcp14>MUST</bcp14> becontiguous.</t> </list></t>contiguous.</li> </ul> <t>If the header field contains text, the binary sequence uses the same encoding.</t> </section> <sectionanchor="convention-for-matching-operator"><name>Conventionanchor="convention-for-matching-operator"> <name>Convention for Matching Operator</name><t>Matching<t>The Matching Operator (MO) is a function applied between a field value provided by the parsed header and thetarget value.Target Value. <xref target="RFC8724"/> defines 4MO.</t>MOs.</t> <t>The naming convention is "mo-" followed by the MO name.</t> <t>The type is"mo-type"</t>"mo-type".</t> <sectionanchor="matching-operator-arguments"><name>Matchinganchor="matching-operator-arguments"> <name>Matching Operatorarguments</name>Arguments</name> <t>They are viewed as a list, built with a tv-struct (see <xref target="target_value"/>).</t> </section> </section> <sectionanchor="convention-for-compression-decompression-actions"><name>Conventionanchor="convention-for-compression-decompression-actions"> <name>Convention for Compression Decompression Actions</name><t>Compression<t>The Compression Decompression Action (CDA) identifies the function to use for compression or decompression. <xref target="RFC8724"/> defines6 CDA.</t>7 CDAs.</t> <t>The naming convention is "cda-" followed by the CDA name.</t> <sectionanchor="compression-decompression-action-arguments"><name>Compressionanchor="compression-decompression-action-arguments"> <name>Compression Decompression Actionarguments</name>Arguments</name> <t>Currently no CDA requires arguments, butin the futuresomeCDACDAs may require one or severalarguments.arguments in the future. They are viewed as alist,list of target-value type.</t> </section> </section> <sectionanchor="frag_types"><name>Fragmentation rule</name>anchor="frag_types"> <name>Fragmentation Rule</name> <t>Fragmentation is optional in the data model and depends on the presence of the "fragmentation" feature.</t> <t>Most of the fragmentation parameters are listed inAnnex D of<xreftarget="RFC8724"/>.</t>target="RFC8724" sectionFormat="of" section="D"/>.</t> <t>Since fragmentationrulesRules work for a specific direction, theyMUST<bcp14>MUST</bcp14> contain a mandatorydirection indicator.Direction Indicator. The type is the same as the one used in compression entries, but bidirectionalMUST NOT<bcp14>MUST NOT</bcp14> be used.</t> <sectionanchor="fragmentation-mode"><name>Fragmentation mode</name>anchor="fragmentation-mode"> <name>Fragmentation Mode</name> <t><xref target="RFC8724"/> defines 3 fragmentation modes:</t><t><list style="symbols"> <t>No Ack: this<ul spacing="normal"> <li>No ACK: This mode isunidirectional,unidirectional; no acknowledgment is sentback.</t> <t>Ackback.</li> <li>ACK Always:eachEach fragmentation window must be explicitly acknowledged before going to thenext.</t> <t>Acknext.</li> <li>ACK on Error: A window is acknowledged only when the receiver detects some missingfragments.</t> </list></t>fragments.</li> </ul> <t>The type is "fragmentation-mode-type". The naming convention is "fragmentation-mode-" followed by the fragmentation mode name.</t> </section> <sectionanchor="fragmentation-header"><name>Fragmentationanchor="fragmentation-header"> <name>Fragmentation Header</name> <t>A data fragment header, starting with therule ID,RuleID, can be sent in the fragmentation direction. <xref target="RFC8724"/> indicates that the SCHC header may be composed of(cf. <xrefthe following (cf. <xref target="Fig-frag-header-8724"/>):</t><t><list style="symbols"> <t>a<ul spacing="normal"> <li>a Datagram Tag(Dtag)(DTag) identifying the datagram being fragmented if the fragmentation applies concurrently on several datagrams. This field isoptionaloptional, and its length is defined by therule.</t> <t>aRule.</li> <li>a Window (W) used inAck-AlwaysACK-Always andAck-on-ErrorACK-on-Error modes. InAck-Always,ACK-Always, its size is 1. InAck-on-Error,ACK-on-Error, it depends on therule.Rule. This field is not needed inNo-Ack mode.</t> <t>aNo-ACK mode.</li> <li>a Fragment Compressed Number (FCN) indicating the fragment/tile position within the window. This field is mandatory on all modes defined in <xref target="RFC8724"/>, and its size is defined by therule.</t> </list></t>Rule.</li> </ul> <figuretitle="Data fragment headeranchor="Fig-frag-header-8724"> <name>Data Fragment Header fromRFC8724" anchor="Fig-frag-header-8724"><artwork><![CDATA[RFC 8724</name> <artwork><![CDATA[ |-- SCHC Fragment Header ----| |-- T --|-M-|-- N --| +-- ... -+- ... -+---+- ... -+--------...-------+~~~~~~~~~~~~~~~~~~~~ | RuleID | DTag | W | FCN | Fragment Payload | padding (as needed) +-- ... -+- ... -+---+- ... -+--------...-------+~~~~~~~~~~~~~~~~~~~~]]></artwork></figure>]]></artwork> </figure> </section> <sectionanchor="last-fragment-format"><name>Last fragment format</name>anchor="last-fragment-format"> <name>Last Fragment Format</name> <t>The last fragment of a datagram is sent withan RCS (Reassemblya Reassembly CheckSequence)Sequence (RCS) field to detect residual transmissionerrorerrors and possible losses in the last window. <xref target="RFC8724"/> defines a single algorithm based on Ethernet CRC computation.</t> <t>The naming convention is "rcs-" followed by the algorithm name.</t> <t>ForAck-on-ErrorACK-on-Error mode, the All-1 fragment may just contain the RCS or can include a tile. The following parameters define the behavior:</t><t><list style="symbols"> <t>all-1-data-no: the<ul spacing="normal"> <li>all-1-data-no: The last fragment contains no data, just theRCS</t> <t>all-1-data-yes: theRCS.</li> <li>all-1-data-yes: The last fragment includes a single tile and theRCS</t> <t>all-1-data-sender-choice: theRCS.</li> <li>all-1-data-sender-choice: The last fragment may or may not contain a single tile. The receiver can detect if a tile ispresent.</t> </list></t>present.</li> </ul> <t>The naming convention is "all-1-data-" followed by the behavior identifier.</t> </section> <sectionanchor="acknowledgment-behavior"><name>Acknowledgment behavior</name>anchor="acknowledgment-behavior"> <name>Acknowledgment Behavior</name> <t>The acknowledgment fragment header goes in the opposite direction of data. <xref target="RFC8724"/> defines the header, which is composed of the following (see <xref target="Fig-frag-ack"/>):</t><t><list style="symbols"> <t>a Dtag<ul spacing="normal"> <li>a DTag (ifpresent).</t> <t>apresent).</li> <li>a mandatorywindowwindow, as in the datafragment.</t> <t>afragment.</li> <li>a C bit giving the status of RCS validation. In case of failure, a bitmap follows, indicating the receivedtile.</t> </list></t>tile.</li> </ul> <figuretitle="Acknowledgment fragment headeranchor="Fig-frag-ack"> <name>Acknowledgment Fragment Header forRFC8724" anchor="Fig-frag-ack"><artwork><![CDATA[RFC 8724</name> <artwork><![CDATA[ |--- SCHC ACK Header ----| |-- T --|-M-| 1 | +-- ... -+- ... -+---+---+~~~~~~~~~~~~~~~~~~ | RuleID | DTag | W |C=1| padding as needed (success) +-- ... -+- ... -+---+---+~~~~~~~~~~~~~~~~~~ +-- ... -+- ... -+---+---+------ ... ------+~~~~~~~~~~~~~~~ | RuleID | DTag | W |C=0|Compressed Bitmap| pad. as needed (failure) +-- ... -+- ... -+---+---+------ ... ------+~~~~~~~~~~~~~~~]]></artwork></figure>]]></artwork> </figure> <t>ForAck-on-Error,ACK-on-Error, SCHC defines when an acknowledgment can be sent. This can be at any time defined by thelayerLayer 2, at the end of a window (FCNall-0)all-0), or as a response to receiving the last fragment (FCN all-1). The naming convention is "ack-behavior" followed by the algorithm name.</t> </section> <sectionanchor="timer-values"><name>Timer values</name>anchor="timer-values"> <name>Timer Values</name> <t>The state machine requires some common values to handle fragmentation correctly.</t><t><list style="symbols"> <t>retransmission-timer<ul spacing="normal"> <li>The Retransmission Timer gives the duration before sending anackACK request(cf. section 8.2.2.4. of <xref target="RFC8724"/>).(cf. <xref target="RFC8724" sectionFormat="of" section="8.2.2.4"/>). If specified, the valueMUST<bcp14>MUST</bcp14> be strictlypositive.</t> <t>inactivity-timerpositive.</li> <li>The Inactivity Timer gives the duration before aborting a fragmentation session (cf.section 8.2.2.4. of<xreftarget="RFC8724"/>).target="RFC8724" sectionFormat="of" section="8.2.2.4"/>). The value 0 explicitly indicates that this timer isdisabled.</t> </list></t>disabled.</li> </ul> <t><xref target="RFC8724"/>dodoes not specify any range for these timers. <xref target="RFC9011"/> recommends a duration of 12 hours. In fact, the value range should be between milliseconds forreal timereal-time systems to severaldays.days for worse-than-best-effort systems. To allow a large range of applications, two parameters must be specified:</t><t><list style="symbols"> <t>the<ul spacing="normal"> <li>the duration of a tick. It is computed by thisformula 2^tick-duration/10^6.formula: 2<sup>tick-duration</sup>/10<sup>6</sup>. When tick-duration is set to 0, the unit is the microsecond. The default value of 20 leads to a unit of 1.048575second.seconds. A value of 32 leads to atick durationtick-duration of about 1 hour 11minutes.</t> <t>theminutes.</li> <li>the number of ticks in the predefined unit. With the default tick-duration value of 20, the timers can cover a range between 1.0secsecond and 19hours coveringhours, as recommended in <xreftarget="RFC9011"/> recommendation.</t> </list></t>target="RFC9011"/>.</li> </ul> </section> <sectionanchor="fragmentation-parameter"><name>Fragmentationanchor="fragmentation-parameter"> <name>Fragmentation Parameter</name> <t>The SCHC fragmentation protocol specifies the number of attempts before aborting through the parameter:</t><t><list style="symbols"> <t>max-ack-requests (cf. section 8.2.2.4. of <xref target="RFC8724"/>).</t> </list></t><ul spacing="normal"> <li>max-ack-requests (cf. <xref target="RFC8724" sectionFormat="of" section="8.2.2.4"/>)</li> </ul> </section> <sectionanchor="layer-2-parameters"><name>Layeranchor="layer-2-parameters"> <name>Layer 2parameters</name>Parameters</name> <t>The data model includes two parameters needed for fragmentation:</t><t><list style="symbols"> <t>l2-word-size:<ul spacing="normal"> <li>l2-word-size: <xref target="RFC8724"/> base fragmentation, in bits, on alayerLayer 2word whichWord that can be of any length. The default value is 8 andcorrespondcorresponds to the default value forbyte aligned layerthe byte-aligned Layer 2. A value of 1 will indicate that there is no alignment and no need forpadding.</t> <t>maximum-packet-size:padding.</li> <li>maximum-packet-size: defines the maximum size of an uncompressed datagram. By default, the value is set to 1280bytes.</t> </list></t>bytes.</li> </ul> <t>They are defined as unsignedintegers,integers; see <xref target="annexA"/>.</t> </section> </section> </section> <sectionanchor="rule-definition"><name>Rule definition</name>anchor="rule-definition"> <name>Rule Definition</name> <t>AruleRule is identified by a uniquerule identifier (rule ID)Rule Identifier (RuleID) comprising both aRule IDRuleID value and aRule IDRuleID length. The YANG grouping rule-id-type defines the structure used to represent arule ID.RuleID. A length of 0 is allowed to represent an implicitrule.</t>Rule.</t> <t>Three natures ofrulesRules are defined in <xref target="RFC8724"/>:</t><t><list style="symbols"> <t>Compression: a<ul spacing="normal"> <li>Compression: A compressionruleRule is associated with therule ID.</t> <t>No compression: thisRuleID.</li> <li>No-compression: This identifies the defaultruleRule used to send a packet integrally whenno compression ruleno-compression Rule was found (see <xreftarget="RFC8724"/> section 6).</t> <t>Fragmentation: fragmentationtarget="RFC8724" sectionFormat="of" section="6"/>).</li> <li>Fragmentation: Fragmentation parameters are associated with therule ID.RuleID. Fragmentation isoptionaloptional, and the feature "fragmentation" should beset.</t> </list></t>set.</li> </ul> <t>The YANG data modelintroducesrespectively introduces these three identities :</t><t><list style="symbols"> <t>nature-compression</t> <t>nature-no-compression</t> <t>nature-fragmentation</t> </list></t><ul spacing="normal"> <li>nature-compression</li> <li>nature-no-compression</li> <li>nature-fragmentation</li> </ul> <t>The naming convention is "nature-" followed by the nature identifier.</t> <t>To access a specificrule,Rule, therule IDRuleID length and value are used as a key. TheruleRule is either a compression or a fragmentationrule.</t>Rule.</t> <sectionanchor="compression-rule"><name>Compression rule</name>anchor="compression-rule"> <name>Compression Rule</name> <t>A compressionruleRule is composed of entries describing its processing. An entry contains all the information defined in <xref target="Fig-ctxt"/> with the types defined above.</t> <t>The compressionruleRule described <xref target="Fig-ctxt"/> is defined by compression-content. It defines a list of compression-rule-entry, indexed by theirfield id, positionField ID, position, and direction. The compression-rule-entry elementrepresentrepresents a lineof the tablein <xref target="Fig-ctxt"/>. Their type reflects the identifier types defined in <xreftarget="comp_types"/></t>target="comp_types"/>.</t> <t>Some checks are performed on the values:</t><t><list style="symbols"> <t>target value MUST be present for<ul spacing="normal"> <li>When MOdifferent from ignore.</t> <t>whenis ignore, no Target Value is needed; for other MOs, there <bcp14>MUST</bcp14> be a Target Value present.</li> <li>When MSB MO is specified, the matching-operator-value must bepresent</t> </list></t>present.</li> </ul> </section> <sectionanchor="fragmentation-rule"><name>Fragmentation rule</name>anchor="fragmentation-rule"> <name>Fragmentation Rule</name> <t>AFragmentation rulefragmentation Rule is composed of entries describing the protocol behavior. Some on them are numerical entries, others are identifiers defined in <xref target="frag_types"/>.</t> </section> <sectionanchor="yang-tree"><name>YANGanchor="yang-tree"> <name>YANG Tree</name> <t>The YANG data model described in this document conforms to the Network Management Datastore Architecture defined in <xref target="RFC8342"/>.</t> <figuretitle="Overviewanchor="Fig-model-overview"> <name>Overview of the SCHCdata model" anchor="Fig-model-overview"><artwork><![CDATA[Data Model</name> <sourcecode type="yangtree"><![CDATA[ module: ietf-schc +--rw schc +--rw rule* [rule-id-value rule-id-length] +--rw rule-id-value uint32 +--rw rule-id-length uint8 +--rw rule-nature nature-type +--rw (nature)? +--:(fragmentation) {fragmentation}? | +--rw fragmentation-mode | | schc:fragmentation-mode-type | +--rw l2-word-size? uint8 | +--rw direction schc:di-type | +--rw dtag-size? uint8 | +--rw w-size? uint8 | +--rw fcn-size uint8 | +--rw rcs-algorithm? rcs-algorithm-type | +--rw maximum-packet-size? uint16 | +--rw window-size? uint16 | +--rw max-interleaved-frames? uint8 | +--rw inactivity-timer | | +--rw ticks-duration? uint8 | | +--rw ticks-numbers? uint16 | +--rw retransmission-timer | | +--rw ticks-duration? uint8 | | +--rw ticks-numbers? uint16 | +--rw max-ack-requests? uint8 | +--rw (mode)? | +--:(no-ack) | +--:(ack-always) | +--:(ack-on-error) | +--rw tile-size? uint8 | +--rw tile-in-all-1? schc:all-1-data-type | +--rw ack-behavior? schc:ack-behavior-type +--:(compression) {compression}? +--rw entry* [field-id field-position direction-indicator] +--rw field-id schc:fid-type +--rw field-length schc:fl-type +--rw field-position uint8 +--rw direction-indicator schc:di-type +--rw target-value* [index] | +--rw index uint16 | +--rw value? binary +--rw matching-operator schc:mo-type +--rw matching-operator-value* [index] | +--rw index uint16 | +--rw value? binary +--rw comp-decomp-action schc:cda-type +--rw comp-decomp-action-value* [index] +--rw index uint16 +--rw value? binary]]></artwork></figure>]]></sourcecode> </figure> </section> </section> <sectionanchor="annexA"><name>YANG Module</name>anchor="annexA"> <name>YANG Data Model</name> <figureanchor="Fig-schc"><artwork><![CDATA[ <CODE BEGINS> file "ietf-schc@2022-10-09.yang"anchor="Fig-schc"> <name>SCHC YANG Data Model</name> <sourcecode type="yang" markers="true" name="ietf-schc@2023-01-28.yang"><![CDATA[ module ietf-schc { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-schc"; prefix schc; organization "IETF IPv6 over Low Power Wide-Area Networks (lpwan)working group";Working Group"; contact "WG Web: <https://datatracker.ietf.org/wg/lpwan/about/> WG List: <mailto:lp-wan@ietf.org> Editor: Laurent Toutain <mailto:laurent.toutain@imt-atlantique.fr> Editor: Ana Minaburo <mailto:ana@ackl.io>"; description" Copyright"Copyright (c)20222023 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Revised BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info). This version of this YANG module is part of RFCXXXX (https://www.rfc-editor.org/info/rfcXXXX);9363 (https://www.rfc-editor.org/info/rfc9363); see the RFC itself for full legal notices. The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document are to be interpreted as described in BCP 14 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here. *************************************************************** GenericDatadata model for the Static Context Header Compression Rule for SCHC, based onRFCRFCs 8724 andRFC8824. Include8824. Including compression,no compressionno-compression, and fragmentationrules.Rules. This module is a YANG data model for SCHCrules (RFCRules (RFCs 8724 andRFC8824).8824). RFC 8724 describes compressionrulesRules inaan abstract way through a table. |-----------------------------------------------------------------| | (FID) Rule 1 | |+-------+--+--+--+------------+-----------------+---------------+| ||Field 1|FL|FP|DI|Target Value|Matching Operator|Comp/Decomp Act|| |+-------+--+--+--+------------+-----------------+---------------+| ||Field 2|FL|FP|DI|Target Value|Matching Operator|Comp/Decomp Act|| |+-------+--+--+--+------------+-----------------+---------------+| ||... |..|..|..| ... | ... | ... || |+-------+--+--+--+------------+-----------------+---------------+| ||Field N|FL|FP|DI|Target Value|Matching Operator|Comp/Decomp Act|| |+-------+--+--+--+------------+-----------------+---------------+| |-----------------------------------------------------------------| This module specifies a global data model that can be used forruleRule exchanges or modification. It specifies both the data model format and the global identifiers used to describe some operations in fields. This data model applies to both compression and fragmentation."; revision2022-10-092023-01-28 { description "Initial version from RFCXXXX.";9363."; reference "RFCXXX:9363 A YANG Data Model for Static Context Header Compression (SCHC)"; } feature compression { description "SCHC compression capabilities are taken into account."; } feature fragmentation { description "SCHC fragmentation capabilities are taken into account."; } // ------------------------- // Field ID type definition //-------------------------- // generic value TV definition identity fid-base-type { description "Field ID base type for all fields."; } identity fid-ipv6-base-type { base fid-base-type; description "Field ID base type for IPv6 headers described in RFC 8200."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-version { base fid-ipv6-base-type; description "IPv6 version field."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-trafficclass { base fid-ipv6-base-type; description "IPv6 Traffic Class field."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-trafficclass-ds { base fid-ipv6-trafficclass; description "IPv6 Traffic Class field:DiffServDiffserv field."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification, RFC 3168 The Addition of Explicit Congestion Notification (ECN) to IP"; } identity fid-ipv6-trafficclass-ecn { base fid-ipv6-trafficclass; description "IPv6 Traffic Class field: ECN field."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification, RFC 3168 The Addition of Explicit Congestion Notification (ECN) to IP"; } identity fid-ipv6-flowlabel { base fid-ipv6-base-type; description "IPv6 Flow Label field."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-payload-length { base fid-ipv6-base-type; description "IPv6 Payload Length field."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-nextheader { base fid-ipv6-base-type; description "IPv6 Next Header field."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-hoplimit { base fid-ipv6-base-type; description "IPv6 Next Header field."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-devprefix { base fid-ipv6-base-type; description "Corresponds to either the source address or the destination address prefix of RFC 8200 depending on whether it is an uplink or a downlink message."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-deviid { base fid-ipv6-base-type; description "Corresponds to either the source address or the destination address IID of RFC 8200 depending on whether it is an uplink or a downlink message."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-appprefix { base fid-ipv6-base-type; description "Corresponds to either the source address or the destination address prefix of RFC 8200 depending on whether it is an uplink or a downlink message."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-ipv6-appiid { base fid-ipv6-base-type; description "Corresponds to either the source address or the destination address IID of RFC 8200 depending on whether it is an uplink or a downlink message."; reference "RFC 8200 Internet Protocol, Version 6 (IPv6) Specification"; } identity fid-udp-base-type { base fid-base-type; description "Field ID base type for UDP headers described in RFC 768."; reference "RFC 768 User Datagram Protocol"; } identity fid-udp-dev-port { base fid-udp-base-type; description "UDP source or destination port, if uplink or downlink communication, respectively."; reference "RFC 768 User Datagram Protocol"; } identity fid-udp-app-port { base fid-udp-base-type; description "UDP destination or source port, if uplink or downlink communication, respectively."; reference "RFC 768 User Datagram Protocol"; } identity fid-udp-length { base fid-udp-base-type; description "UDP length."; reference "RFC 768 User Datagram Protocol"; } identity fid-udp-checksum { base fid-udp-base-type; description "UDP length."; reference "RFC 768 User Datagram Protocol"; } identity fid-coap-base-type { base fid-base-type; description "Field ID base type for UDP headers described."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-version { base fid-coap-base-type; description "CoAP version."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-type { base fid-coap-base-type; description "CoAP type."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-tkl { base fid-coap-base-type; description "CoAP token length."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-code { base fid-coap-base-type; description "CoAP code."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-code-class { base fid-coap-code; description "CoAP code class."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-code-detail { base fid-coap-code; description "CoAP code detail."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-mid { base fid-coap-base-type; description "CoAP message ID."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-token { base fid-coap-base-type; description "CoAP token."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identityfid-coap-option-if-matchfid-coap-option { base fid-coap-base-type; description "Generic CoAP option."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-if-match { base fid-coap-option; description "CoAP option If-Match."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-uri-host { basefid-coap-base-type;fid-coap-option; description "CoAP optionURI-Host.";Uri-Host."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-etag { basefid-coap-base-type;fid-coap-option; description "CoAP optionEtag.";ETag."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-if-none-match { basefid-coap-base-type;fid-coap-option; description "CoAP option if-none-match."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-observe { basefid-coap-base-type;fid-coap-option; description "CoAP option Observe."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-uri-port { basefid-coap-base-type;fid-coap-option; description "CoAP option Uri-Port."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-location-path { basefid-coap-base-type;fid-coap-option; description "CoAP option Location-Path."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-uri-path { basefid-coap-base-type;fid-coap-option; description "CoAP option Uri-Path."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-content-format { basefid-coap-base-type;fid-coap-option; description "CoAP option Content Format."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-max-age { basefid-coap-base-type;fid-coap-option; description "CoAP option Max-Age."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-uri-query { basefid-coap-base-type;fid-coap-option; description "CoAP option Uri-Query."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-accept { basefid-coap-base-type;fid-coap-option; description "CoAP option Accept."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-location-query { basefid-coap-base-type;fid-coap-option; description "CoAP option Location-Query."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-block2 { basefid-coap-base-type;fid-coap-option; description "CoAP option Block2."; reference "RFC 7959 Block-Wise Transfers in the Constrained Application Protocol (CoAP)"; } identity fid-coap-option-block1 { basefid-coap-base-type;fid-coap-option; description "CoAP option Block1."; reference "RFC 7959 Block-Wise Transfers in the Constrained Application Protocol (CoAP)"; } identity fid-coap-option-size2 { basefid-coap-base-type;fid-coap-option; description "CoAP optionsize2.";Size2."; reference "RFC 7959 Block-Wise Transfers in the Constrained Application Protocol (CoAP)"; } identity fid-coap-option-proxy-uri { basefid-coap-base-type;fid-coap-option; description "CoAP option Proxy-Uri."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-proxy-scheme { basefid-coap-base-type;fid-coap-option; description "CoAP optionProxy-scheme.";Proxy-Scheme."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-size1 { basefid-coap-base-type;fid-coap-option; description "CoAP option Size1."; reference "RFC 7252 The Constrained Application Protocol (CoAP)"; } identity fid-coap-option-no-response { basefid-coap-base-type;fid-coap-option; description "CoAP option No response."; reference "RFC 7967 Constrained Application Protocol (CoAP) Option for No Server Response"; } identity fid-oscore-base-type { basefid-coap-type;fid-coap-option; description "OSCORE options (RFC8613) split insub options.";suboptions."; reference "RFC 8824 Static Context Header Compression (SCHC) for the Constrained Application Protocol (CoAP)"; } identity fid-coap-option-oscore-flags { basefid-oscore-base-type;fid-coap-option; description "CoAP optionoscoreOSCORE flags."; reference "RFC 8824 Static Context Header Compression (SCHC) for the Constrained Application Protocol (CoAP) (seesectionSection 6.4)"; } identity fid-coap-option-oscore-piv { basefid-oscore-base-type;fid-coap-option; description "CoAP optionoscoreOSCORE flags."; reference "RFC 8824 Static Context Header Compression (SCHC) for the Constrained Application Protocol (CoAP) (seesectionSection 6.4)"; } identity fid-coap-option-oscore-kid { basefid-oscore-base-type;fid-coap-option; description "CoAP optionoscoreOSCORE flags."; reference "RFC 8824 Static Context Header Compression (SCHC) for the Constrained Application Protocol (CoAP) (seesectionSection 6.4)"; } identity fid-coap-option-oscore-kidctx { basefid-oscore-base-type;fid-coap-option; description "CoAP optionoscoreOSCORE flags."; reference "RFC 8824 Static Context Header Compression (SCHC) for the Constrained Application Protocol (CoAP)(seesectionSection 6.4)"; } //---------------------------------- // Field Length type definition //---------------------------------- identity fl-base-type { description "Used to extendfield lengthField Length functions."; } identity fl-variable { base fl-base-type; description "Residue length inBytebytes is sent as defined for CoAP."; reference "RFC 8824 Static Context Header Compression (SCHC) for the Constrained Application Protocol (CoAP) (seesectionSection 5.3)"; } identity fl-token-length { base fl-base-type; description "Residue length inBytebytes is sent as defined for CoAP."; reference "RFC 8824 Static Context Header Compression (SCHC) for the Constrained Application Protocol (CoAP) (seesectionSection 4.5)"; } //--------------------------------- // Direction Indicator type //--------------------------------- identity di-base-type { description "Used to extenddirection indicators.";Direction Indicators."; } identity di-bidirectional { base di-base-type; description "DirectionIndicationIndicator of bidirectionality."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.1.)";Section 7.1)"; } identity di-up { base di-base-type; description "DirectionIndicationIndicator of uplink."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.1).";Section 7.1)"; } identity di-down { base di-base-type; description "DirectionIndicationIndicator of downlink."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.1).";Section 7.1)"; } //---------------------------------- // Matching Operator type definition //---------------------------------- identity mo-base-type { description "Matching Operator: used in theruleRule selection process to checkisif a Target Value matches the field's value."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation(see* section 7.2).";(see Section 7.2)"; } identity mo-equal { base mo-base-type; description "equal MO."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.3).";Section 7.3)"; } identity mo-ignore { base mo-base-type; description "ignore MO."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.3).";Section 7.3)"; } identity mo-msb { base mo-base-type; description "MSB MO."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.3).";Section 7.3)"; } identity mo-match-mapping { base mo-base-type; description "match-mapping MO."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.3).";Section 7.3)"; } //------------------------------ // CDA type definition //------------------------------ identity cda-base-type { description "Compression Decompression Actions. Specify the action to be applied to the field's value in a specificrule.";Rule."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.2).";Section 7.2)"; } identity cda-not-sent { base cda-base-type; description "not-sent CDA."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.4).";Section 7.4)"; } identity cda-value-sent { base cda-base-type; description "value-sent CDA."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.4).";Section 7.4)"; } identity cda-lsb { base cda-base-type; description"LSB"Least Significant Bit (LSB) CDA."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.4).";Section 7.4)"; } identity cda-mapping-sent { base cda-base-type; description "mapping-sent CDA."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.4).";Section 7.4)"; } identity cda-compute { base cda-base-type; description "compute-* CDA."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.4).";Section 7.4)"; } identity cda-deviid { base cda-base-type; description "DevIID CDA."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.4).";Section 7.4)"; } identity cda-appiid { base cda-base-type; description"AppIID"Application Interface Identifier (AppIID) CDA."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 7.4).";Section 7.4)"; } // -- type definition typedef fid-type { type identityref { base fid-base-type; } description "Field ID generic type."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } typedef fl-type { typeunion { type uint64 { range 1..max; } typeidentityref { base fl-base-type; }}description"Field length either a positive integer expressing the size in bits or a function defined through an identityref.";"Function used to indicate Field Length."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } typedef di-type { type identityref { base di-base-type; } description "Direction in LPWANnetwork,network: up when emitted by the device, down when received by the device, or bi when emitted or received by the device."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } typedef mo-type { type identityref { base mo-base-type; } description "Matching Operator (MO) to comparefieldsfield values withtarget values.";Target Values."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } typedef cda-type { type identityref { base cda-base-type; } description "Compression Decompression Action tocompressioncompress or decompress a field."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } // -- FRAGMENTATION TYPE // -- fragmentation modes identity fragmentation-mode-base-type { description "Define the fragmentation mode."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } identity fragmentation-mode-no-ack { base fragmentation-mode-base-type; description "No-ACK mode."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } identity fragmentation-mode-ack-always { base fragmentation-mode-base-type; description "ACK-Always mode."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } identity fragmentation-mode-ack-on-error { base fragmentation-mode-base-type; description "ACK-on-Error mode."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } typedef fragmentation-mode-type { type identityref { base fragmentation-mode-base-type; } description "Define the type used for fragmentation mode inrules.";Rules."; } // -- Ack behavior identity ack-behavior-base-type { description "Define when to send anAcknowledgment .";Acknowledgment."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } identity ack-behavior-after-all-0 { base ack-behavior-base-type; description "Fragmentation expectsAckACK after sending All-0 fragment."; } identity ack-behavior-after-all-1 { base ack-behavior-base-type; description "Fragmentation expectsAckACK after sending All-1 fragment."; } identity ack-behavior-by-layer2 { base ack-behavior-base-type; description "Layer 2 defines when to send anAck.";ACK."; } typedef ack-behavior-type { type identityref { base ack-behavior-base-type; } description "Define the type used forAckACK behavior inrules.";Rules."; } // -- All-1 with data types identity all-1-data-base-type { description "Type to define when to send an Acknowledgment message."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } identity all-1-data-no { base all-1-data-base-type; description "All-1 contains no tiles."; } identity all-1-data-yes { base all-1-data-base-type; description "All-1 MUST contain a tile."; } identity all-1-data-sender-choice { base all-1-data-base-type; description "Fragmentation process chooses to send tiles or not in All-1."; } typedef all-1-data-type { type identityref { base all-1-data-base-type; } description "Define the type used for All-1 format inrules.";Rules."; } // -- RCS algorithm types identity rcs-algorithm-base-type { description "Identify which algorithm is used to compute RCS. The algorithm also defines the size of the RCS field."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } identity rcs-crc32 { base rcs-algorithm-base-type; description"CRC 32"CRC32 defined as default RCS inRFC8724.RFC 8724. This RCS is 4 bytes long."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } typedef rcs-algorithm-type { type identityref { base rcs-algorithm-base-type; } description "Define the type for RCS algorithm inrules.";Rules."; } // -------- RULE ENTRY DEFINITION ------------ grouping tv-struct { description "Defines thetarget valueTarget Value element. If the header field contains a text, the binary sequence uses the same encoding. field-id allows the conversion to the appropriate type."; leaf index { type uint16; description "Index gives the position in thematching-list.matching list. If only one element is present, index is 0. Otherwise, index is thetheorder in the matching list, starting at 0."; } leaf value { type binary; description "Target Value content as an untyped binary value."; } reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } grouping compression-rule-entry { description "These entriesdefinesdefine a compression entry(i.e.(i.e., aline)line), as defined in RFC 8724. +-------+--+--+--+------------+-----------------+---------------+ |Field 1|FL|FP|DI|Target Value|Matching Operator|Comp/Decomp Act| +-------+--+--+--+------------+-----------------+---------------+ An entry in a compressionruleRule is composed of 7 elements: - Field ID:Thethe header field to becompressed.compressed - Field Length :Eithereither a positive integerofor afunction.function - Field Position:Aa positive (and possibly equal to 0)integer.integer - Direction Indicator:Anan indication in which direction the compression and decompression process iseffective.effective - Targetvalue: AValue: a value against which the headerFieldfield iscompared.compared - Matching Operator:Thethe comparison operation and optional associateparameters.parameters - Comp./Decomp. Action:Thethe compression or decompressionaction,action and optionalparameters.parameters "; leaf field-id { type schc:fid-type; mandatory true; description "Field ID, identify a field in the header with a YANG identity reference."; } leaf field-length { type union { type uint8; type schc:fl-type; } mandatory true; description "Field Length, expressed in number of bits if the length is known when the Rule is created or through a specific function if the length is variable."; } leaf field-position { type uint8; mandatory true; description "FieldpositionPosition in the header is an integer. Position 1 matches the first occurrence of a field in the header, while incremented position values match subsequent occurrences. Position 0 means that this entry matches a field irrespective of its position of occurrence in the header. Be aware that the decompressed header may have position-0 fields ordered differently than they appeared in the original packet."; } leaf direction-indicator { type schc:di-type; mandatory true; description "Direction Indicator, indicate if this field must be considered forruleRule selection or ignored based on the direction(bi directionnal,(bidirectional, only uplink, or only downlink)."; } list target-value { key "index"; uses tv-struct; description "A list ofvaluevalues to compare with the header field value. Iftarget valueTarget Value is a singleton, position must be 0. For use as a matching list for the mo-match-mappingmatching operator,Matching Operator, index should take consecutive values starting from 0."; } leaf matching-operator { type schc:mo-type; must "../target-value or derived-from-or-self(., 'mo-ignore')" { error-message "mo-equal,mo-msbmo-msb, and mo-match-mapping need target-value"; description "target-value is not required for mo-ignore."; } must "not (derived-from-or-self(., 'mo-msb')) or ../matching-operator-value" { error-message "mo-msb requires length value"; } mandatory true; description "MO: Matching Operator."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (see Section7.3).";7.3)"; } list matching-operator-value { key "index"; uses tv-struct; description "Matching Operator Arguments, based on TV structure to allow several arguments. In RFC 8724, only the MSBmatching operatorMatching Operator needs arguments (a single argument, which is the number of most significant bits to be matched)."; } leaf comp-decomp-action { type schc:cda-type; must "../target-value or derived-from-or-self(., 'cda-value-sent') or derived-from-or-self(., 'cda-compute') or derived-from-or-self(., 'cda-appiid') or derived-from-or-self(., 'cda-deviid')" { error-message "cda-not-sent, cda-lsb, and cda-mapping-sent need target-value"; description "target-value is not required for some CDA."; } mandatory true; description "CDA: Compression Decompression Action."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesectionSection 7.4)"; } list comp-decomp-action-value { key "index"; uses tv-struct; description "CDA arguments, based on a TV structure, in order to allow for several arguments. The CDAs specified in RFC 8724 require no argument."; } } // --Rule nature identity nature-base-type { description "Arule,Rule, identified by its RuleID,areis used for a single purpose. RFC 8724 defines23 natures: compression,no compressionno-compression, and fragmentation."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 6).";Section 6)"; } identity nature-compression { base nature-base-type; description "Identify a compressionrule.";Rule."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 6).";Section 6)"; } identity nature-no-compression { base nature-base-type; description "Identify ano compression rule.";no-compression Rule."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 6).";Section 6)"; } identity nature-fragmentation { base nature-base-type; description "Identify a fragmentationrule.";Rule."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation (seesection 6).";Section 6)"; } typedef nature-type { type identityref { base nature-base-type; } description"defines"Defines the type to indicate the nature of therule.";Rule."; } grouping compression-content { list entry { must "derived-from-or-self(../rule-nature, 'nature-compression')" { error-message "Rule nature must be compression"; } key "field-id field-position direction-indicator"; uses compression-rule-entry; description "A compressionruleRule is a list ofruleRule entries, each describing a header field. An entry is identified through a field-id, its position in the packet, and its direction."; } description "Define a compressionruleRule composed of a list of entries."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } grouping fragmentation-content { description "This grouping defines the fragmentation parameters for all the modes(No-ACK, ACK-Always(No ACK, ACK Always, andACK-on-Error)ACK on Error) specified in RFC 8724."; leaf fragmentation-mode { type schc:fragmentation-mode-type; must "derived-from-or-self(../rule-nature, 'nature-fragmentation')" { error-message "Rule nature must be fragmentation"; } mandatory true; description "Which fragmentation mode is used(No-Ack, ACK-Always, ACK-on-Error).";(No ACK, ACK Always, or ACK on Error)."; } leaf l2-word-size { type uint8; default "8"; description "Size, in bits, of thelayerLayer 2word.";Word."; } leaf direction { type schc:di-type; must "derived-from-or-self(., 'di-up') or derived-from-or-self(., 'di-down')" { error-message "Direction for fragmentationrulesRules are up or down."; } mandatory true; description "MUST be up or down, bidirectional MUST NOT be used."; } // SCHC Frag header format leaf dtag-size { type uint8; default "0"; description "Size, in bits, of the DTag field (T variable fromRFC8724).";RFC 8724)."; } leaf w-size { when "derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-on-error') or derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-always') "; type uint8; description "Size, in bits, of the window field (M variable fromRFC8724).";RFC 8724)."; } leaf fcn-size { type uint8; mandatory true; description "Size, in bits, of the FCN field (N variable fromRFC8724).";RFC 8724)."; } leaf rcs-algorithm { type rcs-algorithm-type; default "schc:rcs-crc32"; description "Algorithm used for RCS. The algorithm specifies the RCS size."; } // SCHC fragmentation protocol parameters leaf maximum-packet-size { type uint16; default "1280"; description "When decompression is done, packet size must not strictly exceed this limit, expressed in bytes."; } leaf window-size { type uint16; description "By default, if notspecifiedspecified, the FCN value is 2^w-size - 1.ShouldThis value should notexceed this value.be exceeded. Possible FCN values are between 0 and window-size - 1."; } leaf max-interleaved-frames { type uint8; default "1"; description "Maximum of simultaneously fragmented frames. Maximum value is 2^dtag-size. AllDTAGDTag values can be used, but more than max-interleaved-frames MUST NOT be active at anytime";time."; } container inactivity-timer { leaf ticks-duration { type uint8; default "20"; description "Duration of one tick inmicro-seconds:microseconds: 2^ticks-duration/10^6 = 1.048s."; } leaf ticks-numbers { type uint16 { range "0..max"; } description "Timer duration = ticks-numbers*2^ticks-duration / 10^6."; } description "Durationisin seconds of theinactivity timer,Inactivity Timer; 0 indicates that the timer is disabled. Allows a precision frommicro-secondmicrosecond to year by sending the tick-duration value. For instance:tick-duration /tick-duration: smallest value <-> highest valuev20: 00y 000d 00h 00m 01s.048575<->00y 000d 19h 05m 18s.428159 21: 00y 000d 00h 00m 02s.097151<->00y 001d 14h 10m 36s.856319 22: 00y 000d 00h 00m 04s.194303<->00y 003d 04h 21m 13s.712639 23: 00y 000d 00h 00m 08s.388607<->00y 006d 08h 42m 27s.425279 24: 00y 000d 00h 00m 16s.777215<->00y 012d 17h 24m 54s.850559 25: 00y 000d 00h 00m 33s.554431<->00y 025d 10h 49m 49s.701119 Note that the smallest value is also the incrementationstep, so the timer precision.";step."; } container retransmission-timer { leaf ticks-duration { type uint8; default "20"; description "Duration of one tick inmicro-seconds:microseconds: 2^ticks-duration/10^6 = 1.048s."; } leaf ticks-numbers { type uint16 { range "1..max"; } description "Timer duration = ticks-numbers*2^ticks-duration / 10^6."; } when "derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-on-error') or derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-always') "; description "Duration in seconds of theretransmission timer.Retransmission Timer. Seeinactivity timer.";the Inactivity Timer."; } leaf max-ack-requests { when "derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-on-error') or derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-always') "; type uint8 { range "1..max"; } description "The maximum number of retries for a specific SCHC ACK."; } choice mode { case no-ack; case ack-always; case ack-on-error { leaf tile-size { when "derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-on-error')"; type uint8; description "Size, in bits, of tiles. If not specified or set to 0, tiles fill the fragment."; } leaf tile-in-all-1 { when "derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-on-error')"; type schc:all-1-data-type; description "Defines whether the sender and receiver expect a tile in All-1 fragments or not, or if it is left to the sender's choice."; } leaf ack-behavior { when "derived-from-or-self(../fragmentation-mode, 'fragmentation-mode-ack-on-error')"; type schc:ack-behavior-type; description "Sender behavior to acknowledge, afterAll-0,All-0 or All-1 or when the LPWAN allows it."; } } description "RFC 8724 defines 3 fragmentation modes."; } reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } // Definerule ID. Rule IDRuleID. RuleID is composed of a RuleID value and a //Rule ID LengthRuleID length grouping rule-id-type { leaf rule-id-value { type uint32; description"Rule ID value, this"RuleID value. This value must be unique, considering its length."; } leaf rule-id-length { type uint8 { range "0..32"; } description"Rule ID"RuleID length, in bits. The value 0 is for implicitrules.";Rules."; } description "Arule IDRuleID is composed of a value and a length, expressed in bits."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } // SCHC table for a specific device. container schc { list rule { key "rule-id-value rule-id-length"; uses rule-id-type; leaf rule-nature { type nature-type; mandatory true; description "Specify therule'sRule's nature."; } choice nature { case fragmentation { if-feature "fragmentation"; uses fragmentation-content; } case compression { if-feature "compression"; uses compression-content; } description "AruleRule is for compression, forno-compressionno-compression, or for fragmentation."; } description "Set ofrulescompression,no compressionno-compression, or fragmentationrulesRules identified by their rule-id."; } description "A SCHC set ofrulesRules is composed of a list ofrules whichRules that are used for compression,no-compressionno-compression, or fragmentation."; reference "RFC 8724 SCHC: Generic Framework for Static Context Header Compression and Fragmentation"; } }<CODE ENDS> ]]></artwork></figure>]]></sourcecode> </figure> </section> <sectionanchor="implementation-status"><name>Implementation Status</name> <!--NOTE TO RFC EDITOR: remove the entire section before publication, as well as the reference to RFC 7942. --> <t>This section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in <xref target="RFC7942"/>. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist.</t> <t>According to <xref target="RFC7942"/>, "this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit".</t> <t><list style="symbols"> <t>Openschc is implementing the conversion between the local rule representation and the representation conforming to the data model in JSON and CBOR (following -08 draft).</t> </list></t> </section> <section anchor="iana-considerations"><name>IANAanchor="iana-considerations"> <name>IANA Considerations</name> <t>This document registers one URI and one YANGmodules.</t>data model.</t> <sectionanchor="uri-registration"><name> URIanchor="uri-registration"> <name>URI Registration</name><t>This document requests IANA to register<t>IANA registered the following URI in the "IETF XML Registry" <xref target="RFC3688"/>:</t><ul empty="true"><li> <t>URI: urn:ietf:params:xml:ns:yang:ietf-schc</t> </li></ul> <ul empty="true"><li> <t>Registrant Contact: The IESG.</t> </li></ul> <ul empty="true"><li> <t>XML: N/A;<dl newline="false" spacing="compact"> <dt>URI:</dt> <dd>urn:ietf:params:xml:ns:yang:ietf-schc</dd> <dt>Registrant Contact:</dt> <dd>The IESG.</dd> <dt>XML:</dt> <dd>N/A; the requested URI is an XMLnamespace.</t> </li></ul>namespace.</dd> </dl> </section> <sectionanchor="yang-module-name-registration"><name> YANGanchor="yang-module-name-registration"> <name>YANG Module Name Registration</name><t>This document registers<t>IANA has registered the followingoneYANGmodulesdata model in the "YANG Module Names" registry <xref target="RFC6020"/>.</t><ul empty="true"><li> <t>name: ietf-schc</t> </li></ul> <ul empty="true"><li> <t>namespace: urn:ietf:params:xml:ns:yang:ietf-schc</t> </li></ul> <ul empty="true"><li> <t>prefix: schc</t> </li></ul> <ul empty="true"><li> <t>reference: RFC XXXX Data Model for Static Context Header Compression (SCHC)</t> </li></ul><dl newline="false" spacing="compact"> <dt>name:</dt> <dd>ietf-schc</dd> <dt>namespace:</dt> <dd>urn:ietf:params:xml:ns:yang:ietf-schc</dd> <dt>prefix:</dt> <dd>schc</dd> <dt>reference:</dt> <dd>RFC 9363</dd> </dl> </section> </section> <sectionanchor="security-considerations"><name>Securityanchor="security-considerations"> <name>Security Considerations</name> <t>The YANG module specified in this document defines a schema for data that is designed to be accessed via network management protocols such as NETCONF <xref target="RFC6241"/> or RESTCONF <xref target="RFC8040"/>. The lowest NETCONF layer is the secure transport layer, and the mandatory-to-implement secure transport is Secure Shell (SSH) <xref target="RFC6242"/>. The lowest RESTCONF layer is HTTPS, and the mandatory-to-implement secure transport is TLS <xref target="RFC8446"/>.</t> <t>The Network Configuration Access Control Model (NACM) <xref target="RFC8341"/> provides the means to restrict access for particular NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content.</t><t>This<t>There are a number of datamodel formalizes the rules elements described in <xref target="RFC8724"/> for compression, and fragmentation. As explainednodes defined in this YANG module that are writable/creatable/deletable (i.e., config true, which is thearchitecture document <xref target="I-D.ietf-lpwan-architecture"/>, a rule candefault). These data nodes may beread, created, updatedconsidered sensitive ordeletedvulnerable inresponsesome network environments. Write operations (e.g., edit-config) toa management request. These actionsthese data nodes without proper protection canbe done between two instances of SCHC or betweenhave aSCHC instancenegative effect on network operations. These are the subtrees anda rule repository.</t> <figure><artwork><![CDATA[ create (-------) read +=======+ * ( rules )<------->|Rule |<--|--------> (-------) update |Manager| NETCONF, RESTCONF,... . read delete +=======+ request . +-------+ <===| R & D |<=== ===>| C & F |===> +-------+ ]]></artwork></figure> <t>The ruledata nodes and their sensitivity/vulnerability:</t> <dl newline="false"> <dt>/schc:</dt> <dd>All the data nodes may be modified. The Rule contains sensitiveinformationinformation, such as the application IPv6 address where the device's data will be sent after decompression.A deviceAn attacker may try to modify other devices'rulesRules by changing the application address and may block communication or allows traffic eavesdropping. Therefore, a device must be allowed to modify only its own rules on the remote SCHC instance. The identity of the requester must be validated. This can be done through certificates or access lists.ByModification may be allowed regarding the Field Descriptor (i.e., IPv6 addresses field descriptors should not be modified, but UDP dev port could be changed).</dd> </dl> <t>Some of the readable data nodes in this YANG module may be considered sensitive or vulnerable in some network environments. It is thus important to control read access (e.g., via get, get-config, or notification) to these data nodes. These are the subtrees and data nodes and their sensitivity/vulnerability: </t> <dl newline="false"> <dt>/schc:</dt> <dd>By reading a module, an attacker mayknowlearn the traffic generated by a devicecan generateand can also learn about application addresses or RESTAPI.</t> <t>The full tree is sensitive, since it represents all the elements that can be managed. This module aims to be encapsulated into a YANG module including access controls and identities.</t>API.</dd> </dl> </section> </middle> <back> <displayreference target="I-D.ietf-lpwan-architecture" to="LPWAN-ARCH"/> <references> <name>References</name> <references> <name>Normative References</name> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.0768.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.3688.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6020.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7136.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7252.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8200.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8342.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8613.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8724.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8824.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6241.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8040.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6242.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8446.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8341.xml"/> </references> <references> <name>Informative References</name> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7967.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7950.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8376.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9011.xml"/> <xi:include href="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-lpwan-architecture.xml"/> </references> </references> <sectionanchor="annex-a-example"><name>Annex A : Example</name>anchor="annex-a-example"> <name>Example</name> <t>The informalrulesRules given <xref target="Fig-example-rules"/>willare represented inXMLXML, as shown in <xref target="Fig-XML-rules"/>.</t> <figuretitle="Rules example" anchor="Fig-example-rules"><artwork><![CDATA[anchor="Fig-example-rules"> <name>Rules Example</name> <artwork><![CDATA[ /-------------------------\ |Rule 6/3 110 | |---------------+---+--+--+----------------+-------+----------------\ |IPV6.VER | 4| 1|BI| 6|EQUAL |NOT-SENT | |IPV6.TC | 8| 1|BI| 0|EQUAL |NOT-SENT | |IPV6.FL | 20| 1|BI| 0|IGNORE |NOT-SENT | |IPV6.LEN | 16| 1|BI| |IGNORE |COMPUTE-LENGTH | |IPV6.NXT | 8| 1|BI| 58|EQUAL |NOT-SENT | |IPV6.HOP_LMT | 8| 1|BI| 255|IGNORE |NOT-SENT | |IPV6.DEV_PREFIX| 64| 1|BI|200104701f2101d2|EQUAL |NOT-SENT | |IPV6.DEV_IID | 64| 1|BI|0000000000000003|EQUAL |NOT-SENT | |IPV6.APP_PREFIX| 64| 1|BI| |IGNORE |VALUE-SENT | |IPV6.APP_IID | 64| 1|BI| |IGNORE |VALUE-SENT | \---------------+---+--+--+----------------+-------+----------------/ /-------------------------\ |Rule 12/11 00001100 | !=========================+=========================================\ !^ Fragmentation mode : NoAck header dtag 2 Window 0 FCN 3 UP ^! !^ No Tile size specified ^! !^ RCS Algorithm: RCS_CRC32 ^! \===================================================================/ /-------------------------\ |Rule 100/8 01100100 | |NO COMPRESSIONNO-COMPRESSION RULE | \-------------------------/]]></artwork></figure>]]></artwork> </figure> <figuretitle="XML representationanchor="Fig-XML-rules"> <name>XML Representation of therules." anchor="Fig-XML-rules"><artwork><![CDATA[Rules</name> <sourcecode type="xml"><![CDATA[ <?xml version='1.0' encoding='UTF-8'?> <schc xmlns="urn:ietf:params:xml:ns:yang:ietf-schc"> <rule> <rule-id-value>6</rule-id-value> <rule-id-length>3</rule-id-length> <rule-nature>nature-compression</rule-nature> <entry> <field-id>fid-ipv6-version</field-id> <field-length>4</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-equal</matching-operator> <comp-decomp-action>cda-not-sent</comp-decomp-action> <target-value> <index>0</index> <value>AAY=</value> </target-value> </entry> <entry> <field-id>fid-ipv6-trafficclass</field-id> <field-length>8</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-equal</matching-operator> <comp-decomp-action>cda-not-sent</comp-decomp-action> <target-value> <index>0</index> <value>AA==</value> </target-value> </entry> <entry> <field-id>fid-ipv6-flowlabel</field-id> <field-length>20</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-ignore</matching-operator> <comp-decomp-action>cda-not-sent</comp-decomp-action> <target-value> <index>0</index> <value>AA==</value> </target-value> </entry> <entry> <field-id>fid-ipv6-payload-length</field-id> <field-length>16</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-ignore</matching-operator> <comp-decomp-action>cda-compute</comp-decomp-action> </entry> <entry> <field-id>fid-ipv6-nextheader</field-id> <field-length>8</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-equal</matching-operator> <comp-decomp-action>cda-not-sent</comp-decomp-action> <target-value> <index>0</index> <value>ADo=</value> </target-value> </entry> <entry> <field-id>fid-ipv6-hoplimit</field-id> <field-length>8</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-ignore</matching-operator> <comp-decomp-action>cda-not-sent</comp-decomp-action> <target-value> <index>0</index> <value>AP8=</value> </target-value> </entry> <entry> <field-id>fid-ipv6-devprefix</field-id> <field-length>64</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-equal</matching-operator> <comp-decomp-action>cda-not-sent</comp-decomp-action> <target-value> <index>0</index> <value>IAEEcB8hAdI=</value> </target-value> </entry> <entry> <field-id>fid-ipv6-deviid</field-id> <field-length>64</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-equal</matching-operator> <comp-decomp-action>cda-not-sent</comp-decomp-action> <target-value> <index>0</index> <value>AAAAAAAAAAM=</value> </target-value> </entry> <entry> <field-id>fid-ipv6-appprefix</field-id> <field-length>64</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-ignore</matching-operator> <comp-decomp-action>cda-value-sent</comp-decomp-action> </entry> <entry> <field-id>fid-ipv6-appiid</field-id> <field-length>64</field-length> <field-position>1</field-position> <direction-indicator>di-bidirectional</direction-indicator> <matching-operator>mo-ignore</matching-operator> <comp-decomp-action>cda-value-sent</comp-decomp-action> </entry> </rule> <rule> <rule-id-value>12</rule-id-value> <rule-id-length>11</rule-id-length> <rule-nature>nature-fragmentation</rule-nature> <direction>di-up</direction> <rcs-algorithm>rcs-crc32</rcs-algorithm> <dtag-size>2</dtag-size> <fcn-size>3</fcn-size><fragmentation-mode>fragmentation-mode-no-ack</fragmentation-mode><fragmentation-mode> fragmentation-mode-no-ack </fragmentation-mode> </rule> <rule> <rule-id-value>100</rule-id-value> <rule-id-length>8</rule-id-length> <rule-nature>nature-no-compression</rule-nature> </rule> </schc>]]></artwork></figure>]]></sourcecode> </figure> </section> <sectionanchor="acknowledgements"><name>Acknowledgements</name>anchor="acknowledgments" numbered="false"> <name>Acknowledgments</name> <t>The authors would like to thankDominique Barthel, Carsten Bormann, Ivan Martinez, Alexander Pelov<contact fullname="Dominique Barthel"/>, <contact fullname="Carsten Bormann"/>, <contact fullname="Ivan Martinez"/>, and <contact fullname="Alexander Pelov"/> for their careful reading and valuable inputs. A special thanks forJoe Clarke, Carl Moberg, Tom Petch, Martin Thomson, and Eric Vyncke<contact fullname="Joe Clarke"/>, <contact fullname="Carl Moberg"/>, <contact fullname="Tom Petch"/>, <contact fullname="Martin Thomson"/>, and <contact fullname="Éric Vyncke"/> for their explanations and wiseadvicesadvice when building the model.</t> </section></middle> <back> <references title='Normative References'> <reference anchor='RFC0768' target='https://www.rfc-editor.org/info/rfc768'> <front> <title>User Datagram Protocol</title> <author fullname='J. Postel' initials='J.' surname='Postel'><organization/></author> <date month='August' year='1980'/> </front> <seriesInfo name='STD' value='6'/> <seriesInfo name='RFC' value='768'/> <seriesInfo name='DOI' value='10.17487/RFC0768'/> </reference> <reference anchor='RFC2119' target='https://www.rfc-editor.org/info/rfc2119'> <front> <title>Key words for use in RFCs to Indicate Requirement Levels</title> <author fullname='S. Bradner' initials='S.' surname='Bradner'><organization/></author> <date month='March' year='1997'/> <abstract><t>In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.</t></abstract> </front> <seriesInfo name='BCP' value='14'/> <seriesInfo name='RFC' value='2119'/> <seriesInfo name='DOI' value='10.17487/RFC2119'/> </reference> <reference anchor='RFC3688' target='https://www.rfc-editor.org/info/rfc3688'> <front> <title>The IETF XML Registry</title> <author fullname='M. Mealling' initials='M.' surname='Mealling'><organization/></author> <date month='January' year='2004'/> <abstract><t>This document describes an IANA maintained registry for IETF standards which use Extensible Markup Language (XML) related items such as Namespaces, Document Type Declarations (DTDs), Schemas, and Resource Description Framework (RDF) Schemas.</t></abstract> </front> <seriesInfo name='BCP' value='81'/> <seriesInfo name='RFC' value='3688'/> <seriesInfo name='DOI' value='10.17487/RFC3688'/> </reference> <reference anchor='RFC6020' target='https://www.rfc-editor.org/info/rfc6020'> <front> <title>YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)</title> <author fullname='M. Bjorklund' initials='M.' role='editor' surname='Bjorklund'><organization/></author> <date month='October' year='2010'/> <abstract><t>YANG is a data modeling language used to model configuration and state data manipulated by the Network Configuration Protocol (NETCONF), NETCONF remote procedure calls, and NETCONF notifications. [STANDARDS-TRACK]</t></abstract> </front> <seriesInfo name='RFC' value='6020'/> <seriesInfo name='DOI' value='10.17487/RFC6020'/> </reference> <reference anchor='RFC7136' target='https://www.rfc-editor.org/info/rfc7136'> <front> <title>Significance of IPv6 Interface Identifiers</title> <author fullname='B. Carpenter' initials='B.' surname='Carpenter'><organization/></author> <author fullname='S. Jiang' initials='S.' surname='Jiang'><organization/></author> <date month='February' year='2014'/> <abstract><t>The IPv6 addressing architecture includes a unicast interface identifier that is used in the creation of many IPv6 addresses. Interface identifiers are formed by a variety of methods. This document clarifies that the bits in an interface identifier have no meaning and that the entire identifier should be treated as an opaque value. In particular, RFC 4291 defines a method by which the Universal and Group bits of an IEEE link-layer address are mapped into an IPv6 unicast interface identifier. This document clarifies that those two bits are significant only in the process of deriving interface identifiers from an IEEE link-layer address, and it updates RFC 4291 accordingly.</t></abstract> </front> <seriesInfo name='RFC' value='7136'/> <seriesInfo name='DOI' value='10.17487/RFC7136'/> </reference> <reference anchor='RFC7252' target='https://www.rfc-editor.org/info/rfc7252'> <front> <title>The Constrained Application Protocol (CoAP)</title> <author fullname='Z. Shelby' initials='Z.' surname='Shelby'><organization/></author> <author fullname='K. Hartke' initials='K.' surname='Hartke'><organization/></author> <author fullname='C. Bormann' initials='C.' surname='Bormann'><organization/></author> <date month='June' year='2014'/> <abstract><t>The Constrained Application Protocol (CoAP) is a specialized web transfer protocol for use with constrained nodes and constrained (e.g., low-power, lossy) networks. The nodes often have 8-bit microcontrollers with small amounts of ROM and RAM, while constrained networks such as IPv6 over Low-Power Wireless Personal Area Networks (6LoWPANs) often have high packet error rates and a typical throughput of 10s of kbit/s. The protocol is designed for machine- to-machine (M2M) applications such as smart energy and building automation.</t><t>CoAP provides a request/response interaction model between application endpoints, supports built-in discovery of services and resources, and includes key concepts of the Web such as URIs and Internet media types. CoAP is designed to easily interface with HTTP for integration with the Web while meeting specialized requirements such as multicast support, very low overhead, and simplicity for constrained environments.</t></abstract> </front> <seriesInfo name='RFC' value='7252'/> <seriesInfo name='DOI' value='10.17487/RFC7252'/> </reference> <reference anchor='RFC8174' target='https://www.rfc-editor.org/info/rfc8174'> <front> <title>Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words</title> <author fullname='B. Leiba' initials='B.' surname='Leiba'><organization/></author> <date month='May' year='2017'/> <abstract><t>RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings.</t></abstract> </front> <seriesInfo name='BCP' value='14'/> <seriesInfo name='RFC' value='8174'/> <seriesInfo name='DOI' value='10.17487/RFC8174'/> </reference> <reference anchor='RFC8200' target='https://www.rfc-editor.org/info/rfc8200'> <front> <title>Internet Protocol, Version 6 (IPv6) Specification</title> <author fullname='S. Deering' initials='S.' surname='Deering'><organization/></author> <author fullname='R. Hinden' initials='R.' surname='Hinden'><organization/></author> <date month='July' year='2017'/> <abstract><t>This document specifies version 6 of the Internet Protocol (IPv6). It obsoletes RFC 2460.</t></abstract> </front> <seriesInfo name='STD' value='86'/> <seriesInfo name='RFC' value='8200'/> <seriesInfo name='DOI' value='10.17487/RFC8200'/> </reference> <reference anchor='RFC8342' target='https://www.rfc-editor.org/info/rfc8342'> <front> <title>Network Management Datastore Architecture (NMDA)</title> <author fullname='M. Bjorklund' initials='M.' surname='Bjorklund'><organization/></author> <author fullname='J. Schoenwaelder' initials='J.' surname='Schoenwaelder'><organization/></author> <author fullname='P. Shafer' initials='P.' surname='Shafer'><organization/></author> <author fullname='K. Watsen' initials='K.' surname='Watsen'><organization/></author> <author fullname='R. Wilton' initials='R.' surname='Wilton'><organization/></author> <date month='March' year='2018'/> <abstract><t>Datastores are a fundamental concept binding the data models written in the YANG data modeling language to network management protocols such as the Network Configuration Protocol (NETCONF) and RESTCONF. This document defines an architectural framework for datastores based on the experience gained with the initial simpler model, addressing requirements that were not well supported in the initial model. This document updates RFC 7950.</t></abstract> </front> <seriesInfo name='RFC' value='8342'/> <seriesInfo name='DOI' value='10.17487/RFC8342'/> </reference> <reference anchor='RFC8613' target='https://www.rfc-editor.org/info/rfc8613'> <front> <title>Object Security for Constrained RESTful Environments (OSCORE)</title> <author fullname='G. Selander' initials='G.' surname='Selander'><organization/></author> <author fullname='J. Mattsson' initials='J.' surname='Mattsson'><organization/></author> <author fullname='F. Palombini' initials='F.' surname='Palombini'><organization/></author> <author fullname='L. Seitz' initials='L.' surname='Seitz'><organization/></author> <date month='July' year='2019'/> <abstract><t>This document defines Object Security for Constrained RESTful Environments (OSCORE), a method for application-layer protection of the Constrained Application Protocol (CoAP), using CBOR Object Signing and Encryption (COSE). OSCORE provides end-to-end protection between endpoints communicating using CoAP or CoAP-mappable HTTP. OSCORE is designed for constrained nodes and networks supporting a range of proxy operations, including translation between different transport protocols.</t><t>Although an optional functionality of CoAP, OSCORE alters CoAP options processing and IANA registration. Therefore, this document updates RFC 7252.</t></abstract> </front> <seriesInfo name='RFC' value='8613'/> <seriesInfo name='DOI' value='10.17487/RFC8613'/> </reference> <reference anchor='RFC8724' target='https://www.rfc-editor.org/info/rfc8724'> <front> <title>SCHC: Generic Framework for Static Context Header Compression and Fragmentation</title> <author fullname='A. Minaburo' initials='A.' surname='Minaburo'><organization/></author> <author fullname='L. Toutain' initials='L.' surname='Toutain'><organization/></author> <author fullname='C. Gomez' initials='C.' surname='Gomez'><organization/></author> <author fullname='D. Barthel' initials='D.' surname='Barthel'><organization/></author> <author fullname='JC. Zuniga' initials='JC.' surname='Zuniga'><organization/></author> <date month='April' year='2020'/> <abstract><t>This document defines the Static Context Header Compression and fragmentation (SCHC) framework, which provides both a header compression mechanism and an optional fragmentation mechanism. SCHC has been designed with Low-Power Wide Area Networks (LPWANs) in mind.</t><t>SCHC compression is based on a common static context stored both in the LPWAN device and in the network infrastructure side. This document defines a generic header compression mechanism and its application to compress IPv6/UDP headers.</t><t>This document also specifies an optional fragmentation and reassembly mechanism. It can be used to support the IPv6 MTU requirement over the LPWAN technologies. Fragmentation is needed for IPv6 datagrams that, after SCHC compression or when such compression was not possible, still exceed the Layer 2 maximum payload size.</t><t>The SCHC header compression and fragmentation mechanisms are independent of the specific LPWAN technology over which they are used. This document defines generic functionalities and offers flexibility with regard to parameter settings and mechanism choices. This document standardizes the exchange over the LPWAN between two SCHC entities. Settings and choices specific to a technology or a product are expected to be grouped into profiles, which are specified in other documents. Data models for the context and profiles are out of scope.</t></abstract> </front> <seriesInfo name='RFC' value='8724'/> <seriesInfo name='DOI' value='10.17487/RFC8724'/> </reference> <reference anchor='RFC8824' target='https://www.rfc-editor.org/info/rfc8824'> <front> <title>Static Context Header Compression (SCHC) for the Constrained Application Protocol (CoAP)</title> <author fullname='A. Minaburo' initials='A.' surname='Minaburo'><organization/></author> <author fullname='L. Toutain' initials='L.' surname='Toutain'><organization/></author> <author fullname='R. Andreasen' initials='R.' surname='Andreasen'><organization/></author> <date month='June' year='2021'/> <abstract><t>This document defines how to compress Constrained Application Protocol (CoAP) headers using the Static Context Header Compression and fragmentation (SCHC) framework. SCHC defines a header compression mechanism adapted for Constrained Devices. SCHC uses a static description of the header to reduce the header's redundancy and size. While RFC 8724 describes the SCHC compression and fragmentation framework, and its application for IPv6/UDP headers, this document applies SCHC to CoAP headers. The CoAP header structure differs from IPv6 and UDP, since CoAP uses a flexible header with a variable number of options, themselves of variable length. The CoAP message format is asymmetric: the request messages have a header format different from the format in the response messages. This specification gives guidance on applying SCHC to flexible headers and how to leverage the asymmetry for more efficient compression Rules.</t></abstract> </front> <seriesInfo name='RFC' value='8824'/> <seriesInfo name='DOI' value='10.17487/RFC8824'/> </reference> <reference anchor='RFC6241' target='https://www.rfc-editor.org/info/rfc6241'> <front> <title>Network Configuration Protocol (NETCONF)</title> <author fullname='R. Enns' initials='R.' role='editor' surname='Enns'><organization/></author> <author fullname='M. Bjorklund' initials='M.' role='editor' surname='Bjorklund'><organization/></author> <author fullname='J. Schoenwaelder' initials='J.' role='editor' surname='Schoenwaelder'><organization/></author> <author fullname='A. Bierman' initials='A.' role='editor' surname='Bierman'><organization/></author> <date month='June' year='2011'/> <abstract><t>The Network Configuration Protocol (NETCONF) defined in this document provides mechanisms to install, manipulate, and delete the configuration of network devices. It uses an Extensible Markup Language (XML)-based data encoding for the configuration data as well as the protocol messages. The NETCONF protocol operations are realized as remote procedure calls (RPCs). This document obsoletes RFC 4741. [STANDARDS-TRACK]</t></abstract> </front> <seriesInfo name='RFC' value='6241'/> <seriesInfo name='DOI' value='10.17487/RFC6241'/> </reference> <reference anchor='RFC8040' target='https://www.rfc-editor.org/info/rfc8040'> <front> <title>RESTCONF Protocol</title> <author fullname='A. Bierman' initials='A.' surname='Bierman'><organization/></author> <author fullname='M. Bjorklund' initials='M.' surname='Bjorklund'><organization/></author> <author fullname='K. Watsen' initials='K.' surname='Watsen'><organization/></author> <date month='January' year='2017'/> <abstract><t>This document describes an HTTP-based protocol that provides a programmatic interface for accessing data defined in YANG, using the datastore concepts defined in the Network Configuration Protocol (NETCONF).</t></abstract> </front> <seriesInfo name='RFC' value='8040'/> <seriesInfo name='DOI' value='10.17487/RFC8040'/> </reference> <reference anchor='RFC6242' target='https://www.rfc-editor.org/info/rfc6242'> <front> <title>Using the NETCONF Protocol over Secure Shell (SSH)</title> <author fullname='M. Wasserman' initials='M.' surname='Wasserman'><organization/></author> <date month='June' year='2011'/> <abstract><t>This document describes a method for invoking and running the Network Configuration Protocol (NETCONF) within a Secure Shell (SSH) session as an SSH subsystem. This document obsoletes RFC 4742. [STANDARDS-TRACK]</t></abstract> </front> <seriesInfo name='RFC' value='6242'/> <seriesInfo name='DOI' value='10.17487/RFC6242'/> </reference> <reference anchor='RFC8446' target='https://www.rfc-editor.org/info/rfc8446'> <front> <title>The Transport Layer Security (TLS) Protocol Version 1.3</title> <author fullname='E. Rescorla' initials='E.' surname='Rescorla'><organization/></author> <date month='August' year='2018'/> <abstract><t>This document specifies version 1.3 of the Transport Layer Security (TLS) protocol. TLS allows client/server applications to communicate over the Internet in a way that is designed to prevent eavesdropping, tampering, and message forgery.</t><t>This document updates RFCs 5705 and 6066, and obsoletes RFCs 5077, 5246, and 6961. This document also specifies new requirements for TLS 1.2 implementations.</t></abstract> </front> <seriesInfo name='RFC' value='8446'/> <seriesInfo name='DOI' value='10.17487/RFC8446'/> </reference> <reference anchor='RFC8341' target='https://www.rfc-editor.org/info/rfc8341'> <front> <title>Network Configuration Access Control Model</title> <author fullname='A. Bierman' initials='A.' surname='Bierman'><organization/></author> <author fullname='M. Bjorklund' initials='M.' surname='Bjorklund'><organization/></author> <date month='March' year='2018'/> <abstract><t>The standardization of network configuration interfaces for use with the Network Configuration Protocol (NETCONF) or the RESTCONF protocol requires a structured and secure operating environment that promotes human usability and multi-vendor interoperability. There is a need for standard mechanisms to restrict NETCONF or RESTCONF protocol access for particular users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. This document defines such an access control model.</t><t>This document obsoletes RFC 6536.</t></abstract> </front> <seriesInfo name='STD' value='91'/> <seriesInfo name='RFC' value='8341'/> <seriesInfo name='DOI' value='10.17487/RFC8341'/> </reference> </references> <references title='Informative References'> <reference anchor='RFC7942' target='https://www.rfc-editor.org/info/rfc7942'> <front> <title>Improving Awareness of Running Code: The Implementation Status Section</title> <author fullname='Y. Sheffer' initials='Y.' surname='Sheffer'><organization/></author> <author fullname='A. Farrel' initials='A.' surname='Farrel'><organization/></author> <date month='July' year='2016'/> <abstract><t>This document describes a simple process that allows authors of Internet-Drafts to record the status of known implementations by including an Implementation Status section. This will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature.</t><t>This process is not mandatory. Authors of Internet-Drafts are encouraged to consider using the process for their documents, and working groups are invited to think about applying the process to all of their protocol specifications. This document obsoletes RFC 6982, advancing it to a Best Current Practice.</t></abstract> </front> <seriesInfo name='BCP' value='205'/> <seriesInfo name='RFC' value='7942'/> <seriesInfo name='DOI' value='10.17487/RFC7942'/> </reference> <reference anchor='RFC7967' target='https://www.rfc-editor.org/info/rfc7967'> <front> <title>Constrained Application Protocol (CoAP) Option for No Server Response</title> <author fullname='A. Bhattacharyya' initials='A.' surname='Bhattacharyya'><organization/></author> <author fullname='S. Bandyopadhyay' initials='S.' surname='Bandyopadhyay'><organization/></author> <author fullname='A. Pal' initials='A.' surname='Pal'><organization/></author> <author fullname='T. Bose' initials='T.' surname='Bose'><organization/></author> <date month='August' year='2016'/> <abstract><t>There can be machine-to-machine (M2M) scenarios where server responses to client requests are redundant. This kind of open-loop exchange (with no response path from the server to the client) may be desired to minimize resource consumption in constrained systems while updating many resources simultaneously or performing high-frequency updates. CoAP already provides Non-confirmable (NON) messages that are not acknowledged by the recipient. However, the request/response semantics still require the server to respond with a status code indicating "the result of the attempt to understand and satisfy the request", per RFC 7252.</t><t>This specification introduces a CoAP option called 'No-Response'. Using this option, the client can explicitly express to the server its disinterest in all responses against the particular request. This option also provides granular control to enable expression of disinterest to a particular response class or a combination of response classes. The server MAY decide to suppress the response by not transmitting it back to the client according to the value of the No-Response option in the request. This option may be effective for both unicast and multicast requests. This document also discusses a few examples of applications that benefit from this option.</t></abstract> </front> <seriesInfo name='RFC' value='7967'/> <seriesInfo name='DOI' value='10.17487/RFC7967'/> </reference> <reference anchor='RFC7950' target='https://www.rfc-editor.org/info/rfc7950'> <front> <title>The YANG 1.1 Data Modeling Language</title> <author fullname='M. Bjorklund' initials='M.' role='editor' surname='Bjorklund'><organization/></author> <date month='August' year='2016'/> <abstract><t>YANG is a data modeling language used to model configuration data, state data, Remote Procedure Calls, and notifications for network management protocols. This document describes the syntax and semantics of version 1.1 of the YANG language. YANG version 1.1 is a maintenance release of the YANG language, addressing ambiguities and defects in the original specification. There are a small number of backward incompatibilities from YANG version 1. This document also specifies the YANG mappings to the Network Configuration Protocol (NETCONF).</t></abstract> </front> <seriesInfo name='RFC' value='7950'/> <seriesInfo name='DOI' value='10.17487/RFC7950'/> </reference> <reference anchor='RFC8376' target='https://www.rfc-editor.org/info/rfc8376'> <front> <title>Low-Power Wide Area Network (LPWAN) Overview</title> <author fullname='S. Farrell' initials='S.' role='editor' surname='Farrell'><organization/></author> <date month='May' year='2018'/> <abstract><t>Low-Power Wide Area Networks (LPWANs) are wireless technologies with characteristics such as large coverage areas, low bandwidth, possibly very small packet and application-layer data sizes, and long battery life operation. This memo is an informational overview of the set of LPWAN technologies being considered in the IETF and of the gaps that exist between the needs of those technologies and the goal of running IP in LPWANs.</t></abstract> </front> <seriesInfo name='RFC' value='8376'/> <seriesInfo name='DOI' value='10.17487/RFC8376'/> </reference> <reference anchor='RFC9011' target='https://www.rfc-editor.org/info/rfc9011'> <front> <title>Static Context Header Compression and Fragmentation (SCHC) over LoRaWAN</title> <author fullname='O. Gimenez' initials='O.' role='editor' surname='Gimenez'><organization/></author> <author fullname='I. Petrov' initials='I.' role='editor' surname='Petrov'><organization/></author> <date month='April' year='2021'/> <abstract><t>The Static Context Header Compression and fragmentation (SCHC) specification (RFC 8724) describes generic header compression and fragmentation techniques for Low-Power Wide Area Network (LPWAN) technologies. SCHC is a generic mechanism designed for great flexibility so that it can be adapted for any of the LPWAN technologies.</t><t>This document defines a profile of SCHC (RFC 8724) for use in LoRaWAN networks and provides elements such as efficient parameterization and modes of operation.</t></abstract> </front> <seriesInfo name='RFC' value='9011'/> <seriesInfo name='DOI' value='10.17487/RFC9011'/> </reference> <reference anchor='I-D.ietf-lpwan-architecture'> <front> <title>LPWAN Static Context Header Compression (SCHC) Architecture</title> <author fullname='Alexander Pelov' initials='A.' surname='Pelov'> <organization>Acklio</organization> </author> <author fullname='Pascal Thubert' initials='P.' surname='Thubert'> <organization>Cisco Systems</organization> </author> <author fullname='Ana Minaburo' initials='A.' surname='Minaburo'> <organization>Acklio</organization> </author> <date day='30' month='June' year='2022'/> <abstract> <t> This document defines the LPWAN SCHC architecture. </t> 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