wdiff rfc9428.alt-original rfc9428.txt

6Lo Working Group

Internet Engineering Task Force (IETF) Y. Choi, Ed.
Internet-Draft
Request for Comments: 9428 ETRI
Intended status:
Category: Standards Track Y-G. Hong
Expires: 7 September 2023
ISSN: 2070-1721 Daejon Univ
J-S. Youn
Dongeui Univ
6 March
June 2023

Transmission of IPv6 Packets over Near Field Communication
draft-ietf-6lo-nfc-22

Abstract

Near Field Communication (NFC) is a set of standards for smartphones
and portable devices to establish radio communication with each other
by touching them together or bringing them into proximity, usually no
more than 10 cm apart. NFC standards cover communications communication protocols
and data exchange formats, formats and are based on existing radio-frequency
identification Radio Frequency
Identification (RFID) standards standards, including ISO/IEC 14443 and FeliCa.
The standards include ISO/IEC 18092 and those defined by the NFC
Forum. The NFC technology has been widely implemented and available
in mobile phones, laptop computers, and many other devices. This
document describes how IPv6 is transmitted over NFC using 6LoWPAN IPv6 over
Low-Power Wireless Personal Area Network (6LoWPAN) techniques.

Status of This Memo

This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.

Internet-Drafts are working documents an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force
(IETF). Note that other groups may also distribute
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Drafts is at https://datatracker.ietf.org/drafts/current/.

Internet-Drafts are draft documents valid the IETF community. It has
received public review and has been approved for a maximum publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of six months RFC 7841.

Information about the current status of this document, any errata,
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material or to cite them other than as "work in progress."

This Internet-Draft will expire on 7 September 2023.
https://www.rfc-editor.org/info/rfc9428.

This document is subject to BCP 78 and the IETF Trust's Legal
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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 3
3. Overview of Near Field Communication NFC Technology . . . . . . . 4
3.1. Peer-to-peer Peer-to-Peer Mode of NFC . . . . . . . . . . . . . . . . 4
3.2. Protocol Stack of NFC . . . . . . . . . . . . . . . . . . 4
3.3. NFC-enabled NFC-Enabled Device Addressing . . . . . . . . . . . . . . 6
3.4. MTU of NFC Link Layer . . . . . . . . . . . . . . . . . . 6
4. Specification of IPv6 over NFC . . . . . . . . . . . . . . . 7
4.1. Protocol Stack . . . . . . . . . . . . . . . . . . . . . 7
4.2. Stateless Address Autoconfiguration . . . . . . . . . . . 8
4.3. IPv6 Link-Local Address . . . . . . . . . . . . . . . . . 8
4.4. Neighbor Discovery . . . . . . . . . . . . . . . . . . . 9
4.5. Dispatch Header . . . . . . . . . . . . . . . . . . . . . 10
4.6. Header Compression . . . . . . . . . . . . . . . . . . . 10
4.7. Fragmentation and Reassembly Considerations . . . . . . . 11
4.8. Unicast and Multicast Address Mapping . . . . . . . . . . 11
5. Internet Connectivity Scenarios . . . . . . . . . . . . . . . 12
5.1. NFC-enabled NFC-Enabled Device Network Connected to the Internet . . 12
5.2. Isolated NFC-enabled NFC-Enabled Device Network . . . . . . . . . . . 13
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
9.1.
8.1. Normative References . . . . . . . . . . . . . . . . . . 14
9.2.
8.2. Informative References . . . . . . . . . . . . . . . . . 16
Acknowledgements
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17

1. Introduction

NFC is a set of short-range wireless technologies, typically
requiring a distance between a sender and receiver of 10 cm or less.
NFC operates at 13.56 MHz, MHz and at rates ranging from 106 kbps to 424
kbps, as per the ISO/IEC 18000-3 air interface [ECMA-340]. NFC
builds upon RFID systems by allowing two-way communication between
endpoints. NFC always involves an initiator and a target; the
initiator actively generates an RF a radio frequency (RF) field that can
power a passive target. This enables NFC targets to take very simple
form factors, such as tags, stickers, key fobs, or cards, while
avoiding the need for batteries. NFC peer-to-peer communication is
possible, provided that both devices are powered.

NFC has its a very short transmission range of 10 cm or less, so less; thus, the
other hidden NFC devices behind outside the of that range cannot receive NFC
signals. Therefore, NFC is often regarded as a secure communications
technology.

In order to benefit from Internet connectivity, it is desirable for
NFC-enabled devices to support IPv6, considering IPv6 because of its large address
space, along with
space and the availability of tools for unattended operation, among along
with other advantages. This document specifies how IPv6 is supported
over NFC by using IPv6 over Low-power Wireless Personal Area Network (6LoWPAN) 6LoWPAN techniques [RFC4944], [RFC6282], [RFC4944] [RFC6282] [RFC6775].
6LoWPAN is suitable, considering that it was designed to support IPv6
over IEEE 802.15.4 networks [IEEE802.15.4], [IEEE802.15.4] and some of the
characteristics of the latter are similar to those of NFC.

2. Conventions and Terminology

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 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.

This specification requires readers to be familiar with all the terms
and concepts that are discussed in "IPv6 over Low-Power Wireless
Personal Area Networks (6LoWPANs): Overview, Assumptions, Problem
Statement, and Goals" [RFC4919], "Transmission of IPv6 Packets over
IEEE 802.15.4 Networks" [RFC4944], and "Neighbor Discovery
Optimization for IPv6 over Low-Power Wireless Personal Area Networks
(6LoWPANs) [RFC6775].

6LoWPAN Node (6LN):
A 6LoWPAN node is any host or router participating in a LoWPAN.
This term is used when referring to situations in which either a
host or router can play the role described.

6LoWPAN Router (6LR):
An intermediate router in the LoWPAN that is able to send and
receive Router Advertisements (RAs) and Router Solicitations
(RSs)
(RSs), as well as forward and route IPv6 packets. 6LoWPAN routers
are present only in route-over topologies.

6LoWPAN Border Router (6LBR):
A border router located at the junction of separate 6LoWPAN
networks or between a 6LoWPAN network and another IP network.
There may be one or more 6LBRs at the 6LoWPAN network boundary. A
6LBR is the responsible authority for IPv6 prefix propagation for
the 6LoWPAN network it is serving. An isolated LoWPAN also
contains a 6LBR in the network, which network that provides the prefix(es) for
the isolated network.

3. Overview of Near Field Communication NFC Technology

This section presents an overview of NFC, focusing on the
characteristics of NFC that are most relevant for supporting IPv6.

NFC enables a simple, two-way, two-way interaction between two devices,
allowing users to perform contactless transactions, access digital
content, and connect electronic devices with a single touch. NFC
utilizes key elements in existing standards for contactless card
Technology,
technology, such as ISO/IEC 14443 A&B and JIS-X 6319-4. NFC allows
devices to share information at a distance up to 10 cm with a maximum
physical layer bit rate of 424 kbps.

3.1. Peer-to-peer Peer-to-Peer Mode of NFC

NFC defines three modes of operation: card emulation, peer-to-peer,
and reader/writer. Only the peer-to-peer mode allows two NFC-enabled
devices to communicate with each other to exchange information
bidirectionally. The other two modes do not support two-way
communications
communication between two devices. Therefore, the peer-to-peer mode
MUST be used for IPv6 over NFC.

3.2. Protocol Stack of NFC

NFC defines a protocol stack for the peer-to-peer mode (Figure 1).
The peer-to-peer mode is offered by the Activities Digital Protocol
at the NFC Physical Layer. The NFC Logical Link Layer comprises the
Logical Link Control Protocol (LLCP), and when IPv6 is used over NFC,
it also includes an IPv6-LLCP Binding. IPv6 and its underlying
adaptation Layer layer (i.e., IPv6-over-NFC adaptation layer) Adaptation Layer) are placed
directly on the top of the IPv6-LLCP Binding. An IPv6 datagram is
transmitted by the Logical Link Control Protocol (LLCP) LLCP with guaranteed delivery, delivery and two-way
transmission of information between the peer devices.

Figure 1: Protocol Stack of NFC

The LLCP consists of Logical Link Control (LLC) and MAC Mapping. The
MAC Mapping integrates an existing RF radio frequency (RF) protocol into
the LLCP architecture. The LLC contains three components (Link components: Link
Management, Connection-oriented Transmission, and Connectionless Transmission).
Transmission. The Link Management is responsible for serializing all connection-
oriented
connection-oriented and connectionless LLC PDU (Protocol Data Unit) exchanges
and
exchanges; it is also responsible for the aggregation and
disaggregation of small PDUs. The Connection-oriented Transmission
is responsible for maintaining all connection-oriented data exchanges
exchanges, including connection set-up setup and termination. However, NFC
links do not guarantee perfect wireless link quality, so some type types
of delays delay or variation in delay would be expected in any case. The
Connectionless Transmission is responsible for handling
unacknowledged data exchanges.

In order to send an IPv6 packet over NFC, the packet MUST be passed
down to the LLCP layer of NFC and carried by an Information Field field in
an LLCP Protocol Data Unit (I PDU). The LLCP does not support
fragmentation and reassembly. For IPv6 addressing or address
configuration, the LLCP MUST provide related information, such as
link layer
link-layer addresses, to its upper layer. The LLCP to IPv6 protocol
binding IPv6-LLCP Binding MUST
transfer the Source Service Access Point (SSAP) and Destination
Service Access Point (DSAP) value values to the IPv6 over NFC
adaptation layer. IPv6-over-NFC Adaptation
Layer. The SSAP is a Logical Link Control (LLC) an LLC address of the source NFC-enabled device
with a size of 6 bits, while the DSAP means is an LLC address of the
destination NFC-enabled device. Thus, the SSAP is a source address, address
and the DSAP is a destination address.

In addition, NFC links and host hosts do not need to consider IP header
bits for QoS signaling, signaling or utilize these meaningfully.

3.3. NFC-enabled NFC-Enabled Device Addressing

According to [LLCP-1.4], NFC-enabled devices have two types of 6-bit
addresses (i.e., SSAP and DSAP) to identify service access points.
Several service access points can be installed on a an NFC device.
However, the SSAP and DSAP can be used as identifiers for NFC link
connections with the IPv6 over NFC adaptation layer. IPv6-over-NFC Adaptation Layer. Therefore, the
SSAP can be used to generate an IPv6 interface identifier. Interface Identifier (IID).
Address values between 00h and 0Fh of SSAP and DSAP are reserved for
identifying the well-known service access points, which points that are defined in
the NFC Forum Assigned Numbers Register. Address values between 10h
and 1Fh are assigned by the local LLC to services registered by a
local service environment. In addition, address values between 0x2
and 0x3f are assigned by the local LLC as a result of an upper layer upper-layer
service request. Therefore, the address values between 0x2 and 0x3f
can be used for generating IPv6 interface identifiers. IIDs.

3.4. MTU of NFC Link Layer

As mentioned in Section 3.2, when an IPv6 packet is transmitted, the
packet MUST be passed down to LLCP of NFC and transported to an I PDU
of LLCP of the NFC-enabled peer device.

The information Information field of an I PDU contains a single service data
unit. The maximum number of octets in the information Information field is
determined by the Maximum Information Unit (MIU) for the data link
connection. The default value of the MIU for I PDUs is 128 octets.
The local and remote LLCs each establish and maintain distinct MIU
values for each data link connection endpoint. Also, an LLC may
announce a larger MIU for a data link connection by transmitting an
optional Maximum Information Unit Extension (MIUX) parameter within
the information Information field. If no MIUX parameter is transmitted, the MIU
value is 128 bytes. Otherwise, the MTU size in NFC LLCP MUST be
calculated from the MIU value as follows:

MTU = MIU = 128 + MIUX. MIUX

According to [LLCP-1.4], Figure 2 shows an example of the MIUX
parameter TLV. The Type and Length fields of the MIUX parameter TLV
have each a size of 1 byte. The size of the TLV Value field is 2
bytes.

0 0 1 2 3
0 8 6 1 1
+----------+----------+-----+-----------+
| Type | Length | Value |
+----------+----------+-----+-----------+
| 0x02 | 0x02 | 0x0 | 0x480 |
+----------+----------+-----+-----------+

Figure 2: Example of MIUX Parameter TLV

When the MIUX parameter is used, the TLV Type field is 0x02 and the
TLV Length field is 0x02. The MIUX parameter is encoded into the
least significant 11 bits of the TLV Value field. The unused bits in
the TLV Value field is are set to zero by the sender and ignored by the
receiver. The maximum possible value of the TLV Value field is
0x7FF, and the maximum size of the LLCP MTU is 2175 bytes. As per
the present specification [LLCP-1.4], the MIUX value MUST be 0x480 to
support the IPv6 MTU requirement (of 1280 (1280 bytes) [RFC8200].

4. Specification of IPv6 over NFC

NFC technology has requirements owing to low power consumption and
allowed protocol overhead. 6LoWPAN standards [RFC4944], [RFC6775],
and [RFC4944] [RFC6775]
[RFC6282] provide useful functionality for reducing the overhead of
IPv6 over NFC. This functionality consists of link-local IPv6
addresses and stateless IPv6 address auto-configuration autoconfiguration (see
Section Sections
4.2 and Section 4.3), Neighbor Discovery (see Section 4.4) 4.4), and header
compression (see Section 4.6).

4.1. Protocol Stack

Figure 3 illustrates the IPv6 over NFC IPv6-over-NFC protocol stack. Upper layer Upper-layer
protocols can be transport layer transport-layer protocols (e.g., TCP and UDP),
application layer
application-layer protocols, and others other protocols capable of running
on top of IPv6.

+----------------------------------------+
| Upper Layer Upper-Layer Protocols |
+----------------------------------------+
| IPv6 |
+----------------------------------------+
| Adaptation Layer for IPv6 over NFC |
+----------------------------------------+
| NFC Logical Link Layer |
+----------------------------------------+
| NFC Physical Layer |
+----------------------------------------+

Figure 3: Protocol Stack for IPv6 over NFC

The adaptation layer Adaptation Layer for IPv6 over NFC supports neighbor discovery, Neighbor Discovery,
stateless address auto-configuration, autoconfiguration, header compression, and
fragmentation & and reassembly, based on 6LoWPAN. Note that 6LoWPAN
Header
header compression [RFC6282] does not define header compression for
TCP. The latter can still be supported over by IPv6 over NFC, albeit
without the performance optimization of header compression.

4.2. Stateless Address Autoconfiguration

An NFC-enabled device performs stateless address autoconfiguration as
per [RFC4862]. A 64-bit Interface identifier (IID) IID for an NFC interface is formed by
utilizing the 6-bit NFC SSAP (see Section 3.3). In the viewpoint of
address configuration, such an IID should guarantee a stable IPv6
address during the course of a single
connection, connection because each data
link connection is uniquely identified by the pair of DSAP and SSAP
included in the header of each LLC PDU in NFC.

Following the guidance of [RFC7136], interface identifiers IIDs of all unicast addresses
for NFC-enabled devices are 64 bits long and constructed by using the
generation algorithm of random (but stable)
identifier (RID) identifiers (RIDs) that are stable
[RFC7217].

The RID is an output which is created by the F() algorithm with input
parameters. One of the parameters is Net_Iface, and the NFC Link Link-
Layer
address Address (i.e., the SSAP) MUST be a source of the Net_Iface
parameter. The 6-bit address of the SSAP of NFC is short and easy to can
easily be targeted by attacks of from a third party (e.g., address
scanning). The F() algorithm with SHA-256 can provide secured and
stable IIDs for NFC-enabled devices. In addition, an optional
parameter, Network_ID Network_ID, is used to increase the randomness of the
generated IID with the NFC link layer
address Link-Layer Address (i.e., SSAP). The
secret key SHOULD be of at least 128 bits. It MUST be initialized to a pseudo-random
pseudorandom number [RFC4086].

4.3. IPv6 Link-Local Address

The IPv6 link-local address Link-Local Address for an NFC-enabled device is formed by
appending the IID to the prefix fe80::/64, as depicted in Figure 4.

0 0 0 1
0 1 6 2
0 0 4 7
+----------+------------------+----------------------------+
|1111111010| zeros | Interface Identifier |
+----------+------------------+----------------------------+
. .
. <- - - - - - - - - - - 128 bits - - - - - - - - - - - -> .
. .

Figure 4: IPv6 link-local address Link-Local Address in NFC

The "Interface Identifier" can be a random and stable IID.

4.4. Neighbor Discovery

Neighbor Discovery Optimization for 6LoWPANs ([RFC6775]) [RFC6775] describes the neighbor discovery
Neighbor Discovery approach in several 6LoWPAN topologies, such as
mesh topology. NFC supports mesh topologies, but most of all applications
would use a simple multi-hop network topology or directly connected
peer-to-peer network because the NFC RF range is very short.

* When an NFC 6LoWPAN Node (6LN) 6LN is directly connected to an a 6LBR, the 6LN MUST
register its address with the 6LBR by sending Neighbor
Solicitation (NS) with the Extended Address Registration Option
(EARO) [RFC8505], and [RFC8505]; then Neighbor Advertisement (NA) is started.
When the 6LN and 6LBR are linked to each other, an address is
assigned to the 6LN. In this process, Duplicate Address Detection
(DAD) is not required.

* When two or more NFC LNs 6LNs are connected to the 6LBR, two cases of
topologies can be formed. One is a multi-hop topology, and the
other is a star topology based on the 6LBR. In the multi-hop
topology, LNs which 6LNs that have two or more links with neighbor nodes may
act as routers. In star topology, any of LNs 6LNs can be a router.

* For receiving Router Solicitations RSs and sending Router
Advertisements, RAs, the NFC 6LNs MUST follow Sections 5.3
and 5.4 of [RFC6775].

* When a an NFC device is a 6LoWPAN Router (6LR) 6LR or a 6LBR, the NFC device MUST follow Section
Sections 6 and 7 of [RFC6775].

4.5. Dispatch Header

All IPv6-over-NFC encapsulated datagrams are prefixed by an
encapsulation header stack consisting of a Dispatch dispatch value
[IANA-6LoWPAN]. The only sequence currently defined for IPv6-over- IPv6 over
NFC MUST be the LOWPAN_IPHC compressed IPv6 header (see Section 4.6)
header
followed by a payload, as depicted in Figure 5 and Figure 6. Table 1.

+---------------+---------------+--------------+
| IPHC Dispatch | IPHC Header | Payload |
+---------------+---------------+--------------+

Figure 5: A An IPv6-over-NFC Encapsulated LOWPAN_IPHC Compressed
IPv6 Datagram

The dispatch value (length: 1 octet) (1 octet in length) is treated as an unstructured
namespace. Only a single pattern is used to represent current IPv6-
over-NFC functionality.

+------------+--------------------+-----------+

Figure 6:
+-----------+-------------+---------------------+

Table 1: Dispatch Values

Other IANA-assigned 6LoWPAN Dispatch dispatch values do not apply to this
specification.

4.6. Header Compression

Header compression as defined in [RFC6282], which specifies the
compression format for IPv6 datagrams on top of IEEE 802.15.4, is
REQUIRED in this document as the basis for IPv6 header compression on
top of NFC. All headers MUST be compressed according to RFC 6282 the encoding formats.
formats described in [RFC6282].

Therefore, IPv6 header compression in [RFC6282] MUST be implemented.
Further, implementations MUST also support Generic Header Compression
(GHC) of as described in [RFC7400].

If a 16-bit address is required as a short address, it MUST be formed
by padding the 6-bit NFC SSAP (NFC link-layer node address) Link-Layer Node Address) to the
left with zeros as shown in Figure 7. 6.

0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Padding(all zeros)| NFC Addr. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Figure 7: 6: NFC short address format Short Address Format

4.7. Fragmentation and Reassembly Considerations

IPv6-over-NFC

IPv6 over NFC MUST NOT use fragmentation and reassembly (FAR) at the
adaptation layer for the payloads as discussed in Section 3.4. The
NFC link connection for IPv6 over NFC MUST be configured with an
equivalent MIU size to support the IPv6 MTU requirement (of 1280 (1280 bytes).
To this end, the MIUX value is 0x480.

4.8. Unicast and Multicast Address Mapping

The address resolution procedure for mapping IPv6 non-multicast
addresses into NFC link-layer addresses Link-Layer Addresses follows the general
description in Section Sections 4.6.1 and 7.2 of [RFC4861], unless otherwise
specified.

The Source/Target link-layer Link-Layer Address option has the following form
when the addresses are 6-bit NFC SSAP/DSAP (NFC link-layer node
addresses). Link-Layer Node
Addresses).

0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length=1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+- Padding (all zeros) -+
| |
+- +-+-+-+-+-+-+
| | NFC Addr. |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Figure 8: 7: Unicast address mapping Address Mapping

Option fields:
Type:

-
1: This is for the Source Link-layer address.

- Link-Layer Address.

2: This is for the Target Link-layer address. Link-Layer Address.

Length:

-
This is the length of this option (including the type Type and
length
Length fields) in units of 8 bits. The value of this field is
1 for 6-bit NFC node addresses.

NFC address:

-
The 6-bit address in canonical bit order. This is the unicast
address the interface currently responds to.

The NFC Link Layer does not support multicast. Therefore, packets
are always transmitted by unicast between two NFC-enabled devices. Even
in the case where a 6LBR is attached to multiple 6LNs, the 6LBR
cannot do a multicast to all the connected 6LNs. If the 6LBR needs to
send a multicast packet to all its 6LNs, it has to replicate the
packet and unicast it on each link. However, this is not energy-
efficient, and
efficient; the central node, which is battery-powered, must take
particular care of power consumption. To further conserve power, the
6LBR MUST keep track of multicast listeners at NFC link-level
granularity (not at subnet granularity), and it MUST NOT forward
multicast packets to 6LNs that have not registered as listeners for
multicast groups the packets belong to. In the opposite direction, a
6LN always has to send packets to or through the 6LBR. Hence, when a
6LN needs to transmit an IPv6 multicast packet, the 6LN will unicast
the corresponding NFC packet to the 6LBR.

5. Internet Connectivity Scenarios

5.1. NFC-enabled NFC-Enabled Device Network Connected to the Internet

Figure 9 8 illustrates an example of an NFC-enabled device network
connected to the Internet. The distance between 6LN and 6LBR is
typically 10 cm or less. For example, a laptop computer that is
connected to the Internet (e.g. (e.g., via Wi-Fi, Ethernet, etc.) may also
support NFC and act as a 6LBR. Another NFC-enabled device may run as
a 6LN and communicate with the 6LBR, as long as both are within each
other's range.

NFC link
6LN ------------------- 6LBR -------( Internet )--------- CN
. . .
. <- - - - Subnet - - -> . < - - - IPv6 connection - - -> .
. . to the Internet .

Figure 9: NFC-enabled device network connected 8: NFC-Enabled Device Network Connected to the Internet

Two or more 6LNs may be connected with a 6LBR, but each connection
uses a different IPv6 prefix. The 6LBR is acting as a router and
forwarding packets between 6LNs and the Internet. Also, the 6LBR
MUST ensure address collisions do not occur because the 6LNs are
connected to the 6LBR like a start topology, so the 6LBR checks
whether or not IPv6 addresses are duplicate or not, duplicates, since 6LNs need to
register their addresses with the 6LBR.

5.2. Isolated NFC-enabled NFC-Enabled Device Network

In some scenarios, the NFC-enabled device network may permanently be
a simple isolated network as shown in the Figure 10. 9.

Figure 10: 9: Isolated NFC-enabled device network NFC-Enabled Device Network

In multihop (i.e., more complex) topologies, the 6LR can also do the
same task, but then Duplicate Address Detection (DAD) task. DAD requires the extensions for multihop networks networks, such
as the ones in [RFC6775].

6. IANA Considerations

There are

This document has no IANA considerations related to this document. actions.

7. Security Considerations

Neighbor Discovery in unencrypted wireless device networks may be
susceptible to various threats as described in [RFC3756].

Per the NFC Logical Link Control Protocol [LLCP-1.4]:

* LLCP of NFC provides protection of user data to ensure
confidentiality of communications. The confidentiality mechanism
involves the encryption of user service data with a secret key
that has been established during link activation.

* LLCP of NFC has two modes (i.e., ad-hoc ad hoc mode and authenticated
mode) for secure data transfer. Ad-hoc Ad hoc secure data transfer can
be established between two communication parties without any prior
knowledge of the communication partner. Ad-hoc Ad hoc secure data
transfer can be vulnerable to Man-In-The-Middle (MITM) on-path attacks. Authenticated
secure data transfer provides protection against
Man-In-The-Middle (MITM) on-path attacks.
In the initial bonding step, the two communicating parties store a
shared secret along with a Bonding Identifier.

* For all subsequent interactions, the communicating parties re-use reuse
the shared secret and compute only the unique encryption key for
that session. Secure data transfer is based on the cryptographic
algorithms defined in the NFC Authentication Protocol [NAP-1.0].

Furthermore, NFC is considered by many to offer intrinsic security
properties due to its short link range. When interface identifiers
(IIDs) IIDs are generated,
devices and users are required to consider mitigating various
threats, such as correlation of activities over time, location
tracking, device-specific vulnerability exploitation, and address
scanning. However, IPv6-over-NFC IPv6 over NFC uses a random (but
stable) identifier (RID) an RID [RFC7217] as an IPv6 interface identifier,
and
IID; NFC applications use short-lived connections, connections and a different
address is used for each connection, connection where the latter is of extremely
short duration.

8. References

9.1.

8.1. Normative References

[LLCP-1.4] NFC Forum, "NFC Logical "Logical Link Control Protocol, Version
1.4", NFC Forum Protocol Technical Specification , January 2021,
Specification", Version 1.4, December 2022,
<https://nfc-forum.org/build/specifications>.

[NAP-1.0] NFC Forum, "NFC Authentication Protocol Candidate Technical Specification, Version 1.0", NFC Forum Technical
Specification ,
Specification", Verison 1.0, December 2020, 2022,
<https://nfc-forum.org/build/specifications>.

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.

[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,
"Randomness Requirements for Security", BCP 106, RFC 4086,
DOI 10.17487/RFC4086, June 2005,
<https://www.rfc-editor.org/info/rfc4086>.

[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>.

[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862,
DOI 10.17487/RFC4862, September 2007,
<https://www.rfc-editor.org/info/rfc4862>.

[RFC4919] Kushalnagar, N., Montenegro, G., and C. Schumacher, "IPv6
over Low-Power Wireless Personal Area Networks (6LoWPANs):
Overview, Assumptions, Problem Statement, and Goals",
RFC 4919, DOI 10.17487/RFC4919, August 2007,
<https://www.rfc-editor.org/info/rfc4919>.

[RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler,
"Transmission of IPv6 Packets over IEEE 802.15.4
Networks", RFC 4944, DOI 10.17487/RFC4944, September 2007,
<https://www.rfc-editor.org/info/rfc4944>.

[RFC6282] Hui, J., Ed. and P. Thubert, "Compression Format for IPv6
Datagrams over IEEE 802.15.4-Based Networks", RFC 6282,
DOI 10.17487/RFC6282, September 2011,
<https://www.rfc-editor.org/info/rfc6282>.

[RFC6775] Shelby, Z., Ed., Chakrabarti, S., Nordmark, E., and C.
Bormann, "Neighbor Discovery Optimization for IPv6 over
Low-Power Wireless Personal Area Networks (6LoWPANs)",
RFC 6775, DOI 10.17487/RFC6775, November 2012,
<https://www.rfc-editor.org/info/rfc6775>.

[RFC7136] Carpenter, B. and S. Jiang, "Significance of IPv6
Interface Identifiers", RFC 7136, DOI 10.17487/RFC7136,
February 2014, <https://www.rfc-editor.org/info/rfc7136>.

[RFC7217] Gont, F., "A Method for Generating Semantically Opaque
Interface Identifiers with IPv6 Stateless Address
Autoconfiguration (SLAAC)", RFC 7217,
DOI 10.17487/RFC7217, April 2014,
<https://www.rfc-editor.org/info/rfc7217>.

[RFC7400] Bormann, C., "6LoWPAN-GHC: Generic Header Compression for
IPv6 over Low-Power Wireless Personal Area Networks
(6LoWPANs)", RFC 7400, DOI 10.17487/RFC7400, November
2014, <https://www.rfc-editor.org/info/rfc7400>.

[RFC8025] Thubert, P., Ed. and R. Cragie, "IPv6 over Low-Power
Wireless Personal Area Network (6LoWPAN) Paging Dispatch",
RFC 8025, DOI 10.17487/RFC8025, November 2016,
<https://www.rfc-editor.org/info/rfc8025>.

[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.

[RFC8200] Deering, S., Hinden, R., S. and RFC Publisher, R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.

[RFC8505] Thubert, P., Ed., Nordmark, E., Chakrabarti, S., and C.
Perkins, "Registration Extensions for IPv6 over Low-Power
Wireless Personal Area Network (6LoWPAN) Neighbor
Discovery", RFC 8505, DOI 10.17487/RFC8505, November 2018,
<https://www.rfc-editor.org/info/rfc8505>.

9.2.

8.2. Informative References

[ECMA-340] ECMA International, "Near Field Communication - Interface
and Protocol (NFCIP-
1) (NFCIP-1)", 3rd Ed.", Edition, ECMA International , 340, June 2013,
<https://www.ecma-international.org/wp-content/uploads/
ECMA-340_3rd_edition_june_2013.pdf>.

[IANA-6LoWPAN]
Internet Assigned Numbers Authority (IANA),
IANA, "IPv6 Low Power Personal Area Network Parameters", 3 December 2021,
<https://www.iana.org/assignments/_6lowpan-parameters>.

[IEEE802.15.4]
IEEE Computer Society,
IEEE, "IEEE Standard for Low-Rate Wireless Networks, IEEE Std. 802.15.4-2020", Networks", IEEE ,
Std 802.15.4-2020, DOI 10.1109/IEEESTD.2020.9144691, July
2020, <https://standards.ieee.org/ieee/802.15.4/7029/>. <https://ieeexplore.ieee.org/document/9144691>.

[RFC3756] Nikander, P., Ed., Kempf, J., and E. Nordmark, "IPv6
Neighbor Discovery (ND) Trust Models and Threats",
RFC 3756, DOI 10.17487/RFC3756, May 2004,
<https://www.rfc-editor.org/info/rfc3756>.

Acknowledgements

We are grateful to the members of the IETF 6lo working group. Working Group.

Michael Richardson, Suresh Krishnan, Pascal Thubert, Carsten Bormann,
Alexandru Petrescu, James Woodyatt, Dave Thaler, Samita Chakrabarti,
Gabriel Montenegro, Erik Kline Kline, and Carles Gomez Montenegro have
provided valuable feedback for this document.

Authors' Addresses

Younghwan Choi (editor)
Electronics and Telecommunications Research Institute
218 Gajeongno, Yuseung-gu
Daejeon
34129
South Korea
Phone: +82 42 860 1429
Email: yhc@etri.re.kr

Yong-Geun Hong
Daejon University
62 Daehak-ro, Dong-gu
Daejeon
34520
South Korea
Phone: +82 42 280 4841
Email: yonggeun.hong@gmail.com

Joo-Sang Youn
DONG-EUI University
176 Eomgwangno Busan_jin_gu
Busan
614-714
South Korea
Phone: +82 51 890 1993
Email: joosang.youn@gmail.com