| RFC 9453 | 6lo Applicability and Use Cases | September 2023 |
| Hong, et al. | Informational | [Page] |
This document describes the applicability of IPv6 over constrained-node networks (6lo) and provides practical deployment examples. In addition to IEEE Std 802.15.4, various link-layer technologies are used as examples, such as ITU-T G.9959 (Z-Wave), Bluetooth Low Energy (Bluetooth LE), Digital Enhanced Cordless Telecommunications - Ultra Low Energy (DECT-ULE), Master-Slave/Token Passing (MS/TP), Near Field Communication (NFC), and Power Line Communication (PLC). This document targets an audience who would like to understand and evaluate running end-to-end IPv6 over the constrained-node networks for local or Internet connectivity.¶
This document is not an Internet Standards Track specification; it is published for informational purposes.¶
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are candidates for any level of Internet Standard; see Section 2 of RFC 7841.¶
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc9453.¶
Copyright (c) 2023 IETF Trust and the persons identified as the document authors. All rights reserved.¶
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.¶
Running IPv6 on constrained-node networks presents challenges due to the characteristics of these networks, such as small packet size, low power, low bandwidth, and large number of devices, among others [RFC4919] [RFC7228]. For example, many IEEE Std 802.15.4 variants [IEEE-802.15.4] exhibit a frame size of 127 octets, whereas IPv6 requires its underlying layer to support an MTU of 1280 bytes. Furthermore, those IEEE Std 802.15.4 variants do not offer fragmentation and reassembly functionality. (It is noted that IEEE Std 802.15.9-2021 provides a multiplexing and fragmentation layer for the IEEE Std 802.15.4 [IEEE-802.15.9].) Therefore, an appropriate adaptation layer supporting fragmentation and reassembly must be provided below IPv6. Also, the limited IEEE Std 802.15.4 frame size and low energy consumption requirements motivate the need for packet header compression. The IETF IPv6 over Low-Power Wireless Personal Area Network (6LoWPAN) Working Group published a suite of specifications that provides an adaptation layer to support IPv6 over IEEE Std 802.15.4 comprising the following functionalities:¶
As Internet of Things (IoT) services become more popular, the IETF has defined adaptation layer functionality to support IPv6 over various link-layer technologies other than IEEE Std 802.15.4, such as Bluetooth Low Energy (Bluetooth LE), ITU-T G.9959 (Z-Wave), Digital Enhanced Cordless Telecommunications - Ultra Low Energy (DECT-ULE), Master-Slave/Token Passing (MS/TP), Near Field Communication (NFC), and Power Line Communication (PLC). The 6lo adaptation layers use a variation of the 6LoWPAN stack applied to each particular link-layer technology.¶
The 6LoWPAN Working Group produced the document entitled "Design and Application Spaces for IPv6 over Low-Power Wireless Personal Area Networks (6LoWPANs)" [RFC6568], which describes potential application scenarios and use cases for LoWPANs. The present document aims to provide guidance to an audience that is new to the IPv6 over constrained-node networks (6lo) concept and want to assess its application to the constrained-node network of their interest. This 6lo applicability document describes a few sets of practical 6lo deployment scenarios and use-case examples. In addition, it considers various network design space dimensions, such as Deployment, Network Size, Power Source, Connectivity, Multi-Hop Communication, Traffic pattern, Mobility, and QoS requirements (see Appendix A).¶
This document provides the applicability and use cases of 6lo, considering the following aspects:¶
Note that the use of "master" and "slave" have been retained in this document to align with use within the industry (e.g., [TIA-485-A] and [BACnet]).¶
The ITU-T G.9959 Recommendation [G.9959] targets LoWPANs and defines physical-layer and link-layer functionality. Physical layers of 9.6 kbit/s, 40 kbit/s, and 100 kbit/s are supported. [G.9959] defines how a unique 32-bit HomeID network identifier is assigned by a network controller and how an 8-bit NodeID host identifier is allocated to each node. NodeIDs are unique within the network identified by the HomeID. The G.9959 HomeID represents an IPv6 subnet that is identified by one or more IPv6 prefixes [RFC7428]. ITU-T G.9959 can be used for smart home applications, and the transmission range is 100 meters per hop.¶
Bluetooth LE was introduced in Bluetooth 4.0, enhanced in Bluetooth 4.1, and developed further in successive versions. The data rate of Bluetooth LE is 125 kb/s, 500 kb/s, 1 Mb/s, 2 Mb/s; and max transmission range is around 100 meters (outdoors). The Bluetooth Special Interest Group (Bluetooth SIG) has also published the Internet Protocol Support Profile (IPSP). The IPSP enables discovery of IP-enabled devices and establishment of link-layer connections for transporting IPv6 packets. IPv6 over Bluetooth LE is dependent on both Bluetooth 4.1 [BTCorev5.4] and IPSP 1.0 [IPSP] or newer.¶
Many devices such as mobile phones, notebooks, tablets, and other handheld computing devices that support Bluetooth 4.0 or subsequent versions also support the low-energy variant of Bluetooth. Bluetooth LE is also being included in many different types of accessories that collaborate with mobile devices. An example of a use case for a Bluetooth LE accessory is a heart rate monitor that sends data via the mobile phone to a server on the Internet [RFC7668]. A typical usage of Bluetooth LE is smartphone-based interaction with constrained devices. Bluetooth LE was originally designed to enable star topology networks. However, recent Bluetooth versions support the formation of extended topologies, and IPv6 support for mesh networks of Bluetooth LE devices has been developed [RFC9159].¶
DECT-ULE is a low-power air interface technology that is designed to support both circuit-switched services, such as voice communication, and packet-mode data services at modest data rate [TS102.939-1] [TS102.939-2].¶
The DECT-ULE protocol stack consists of the physical layer operating at frequencies in the dedicated 1880 - 1920 MHz frequency band depending on the region and uses a symbol rate of 1.152 Mbps. Radio bearers are allocated by use of Frequency-Division Multiplex (FDMA), Time-Division Multiple Access (TDMA), and Time-Division Duplex (TDD) techniques. The coverage distance is from 70 meters (indoors) to 600 meters (outdoors).¶
In its generic network topology, DECT is defined as a cellular network technology. However, the most common configuration is a star network with a single Fixed Part (FP) defining the network with a number of Portable Parts (PPs) attached. The Medium Access Control (MAC) layer supports classical DECT as this is used for services like discovery, pairing, and security features. All these features have been reused from DECT.¶
The DECT-ULE device can switch to the ULE mode of operation, utilizing the new Ultra Low Energy (ULE) MAC layer features. The DECT-ULE Data Link Control (DLC) provides multiplexing as well as segmentation and re-assembly for larger packets from layers above. The DECT-ULE layer also implements per-message authentication and encryption. The DLC layer ensures packet integrity and preserves packet order, but delivery is based on best effort.¶
The current DECT-ULE MAC layer standard supports low bandwidth data broadcast. However, the usage of this broadcast service has not yet been standardized for higher layers [RFC8105]. DECT-ULE can be used for smart metering in a home.¶
MS/TP is a MAC protocol for the RS-485 [TIA-485-A] physical layer and is used primarily in building automation networks.¶
An MS/TP device is typically based on a low-cost microcontroller with limited processing power and memory. These constraints, together with low data rates and a small MAC address space, are similar to those faced in 6LoWPAN networks. MS/TP differs significantly from 6LoWPAN in at least three respects:¶
MS/TP is designed to enable multidrop networks over shielded twisted pair wiring. It can support network segments up to 1000 meters in length at a data rate of 115.2 kbit/s or segments up to 1200 meters in length at lower bit rates. An MS/TP interface requires only a Universal Asynchronous Receiver Transmitter (UART), an RS-485 [TIA-485-A] transceiver with a driver that can be disabled, and a 5 ms resolution timer. The MS/TP MAC is typically implemented in software.¶
Because of its long range (~1 km), MS/TP can be used to connect remote devices (such as district heating controllers) to the nearest building control infrastructure over a single link [RFC8163].¶
NFC technology enables secure interactions between electronic devices, allowing consumers to perform contactless transactions, access digital content, and connect electronic devices with a single touch [LLCP-1.4]. The distance between sender and receiver is 10 cm or less. NFC complements many popular consumer-level wireless technologies by utilizing the key elements in existing standards for contactless card technology.¶
Extending the capability of contactless card technology, NFC also enables devices to share information at a distance that is less than 10 cm with a maximum communication speed of 424 kbps. Users can share business cards, make transactions, access information from a smart poster, or provide credentials for access control systems with a simple touch.¶
NFC's bidirectional communication ability is suitable for establishing connections with other technologies by the simplicity of touch. In addition to the easy connection and quick transactions, simple data sharing is available [RFC9428]. NFC can be used for secure transfer services where privacy is important.¶
PLC is a data transmission technique that utilizes power conductors as the medium [RFC9354]. Unlike other dedicated communication infrastructure, power conductors are widely available indoors and outdoors. Moreover, wired technologies cause less interference to the radio medium than wireless technologies and are more reliable than their wireless counterparts.¶
The table below shows some available open standards defining PLC.¶
| PLC Systems | Frequency Range | Type | Data Rate | Distance |
|---|---|---|---|---|
| IEEE 1901 | < 100 MHz | Broadband | 200 Mbps | 1000 m |
| IEEE 1901.1 | < 12 MHz | PLC-IoT | 10 Mbps | 2000 m |
| IEEE 1901.2 | < 500 kHz | Narrowband | 200 kbps | 3000 m |
| G3-PLC | < 500 kHz | Narrowband | 234 kbps | 3000 m |
IEEE Std 1901 [IEEE-1901] defines a broadband variant of PLC, but it is only effective within short range. This standard addresses the requirements of high data rates such as the Internet, HDTV, audio, and gaming.¶
IEEE Std 1901.1 [IEEE-1901.1] defines a medium frequency band (less than 12 MHz) broadband PLC technology for smart grid applications based on Orthogonal Frequency Division Multiplexing (OFDM). By achieving an extended communication range with medium speeds, this standard can be applied in both indoor and outdoor scenarios, such as Advanced Metering Infrastructure (AMI), street lighting, electric vehicle charging, and a smart city.¶
IEEE Std 1901.2 [IEEE-1901.2] defines a narrowband variant of PLC with a lower data rate but a significantly higher transmission range that could be used in an indoor or even an outdoor environment. A typical use case of PLC is a smart grid.¶
G3-PLC [G3-PLC] is a narrowband PLC technology that is based on the ITU-T G.9903 Recommendation [G.9903]. The ITU-T G.9903 Recommendation contains the physical layer and data link-layer specification for the G3-PLC narrowband OFDM power line communication transceivers, for communications via alternating current and direct current electric power lines over frequency bands below 500 kHz.¶
In the above subsections, various 6lo link-layer technologies are described. The following table shows the dominant parameters of each use case corresponding to the 6lo link-layer technology.¶
| Z-Wave | Bluetooth LE | DECT-ULE | MS/TP | NFC | PLC | |
|---|---|---|---|---|---|---|
| Usage | Home Autom. | Interact w/ Smart Phone | Meter Reading | Building Autom. | Secure Transfer | Smart Grid |
| Topology & Subnet |
L2-mesh or L3-mesh |
Star & Mesh | Star, No mesh | MS/TP, No mesh | P2P, L2‑mesh | Star Tree Mesh |
| Mobility Req. | No | Yes | No | No | Yes | No |
| Buffering Req. | Yes | Yes | Yes | Yes | Yes | Yes |
| Latency, QoS Req. |
Yes | Yes | Yes | Yes | Yes | Yes |
| Frequent Tx Req. |
No | No | No | Yes | No | No |
| RFC | RFC 7428 | RFC 7668 RFC 9159 |
RFC 8105 | RFC 8163 | RFC 9428 | RFC 9354 |
6lo aims to reuse and/or adapt existing 6LoWPAN functionality in order to efficiently support IPv6 over a variety of IoT L2 technologies. The following guideline targets new candidate-constrained L2 technologies that may be considered for running a modified 6LoWPAN stack on top. The modification of the 6LoWPAN stack should be based on the following:¶
Wireless Smart Ubiquitous Network (Wi-SUN) [Wi-SUN] is a technology based on IEEE Std 802.15.4g [IEEE-802.15.4]. Wi-SUN networks support star and mesh topologies as well as hybrid star/mesh deployments, but these are typically laid out in a mesh topology where each node relays data for the network to provide network connectivity. Wi-SUN networks are deployed on both grid-powered and battery-operated devices [RFC8376].¶
The main application domains using Wi-SUN are smart utility and smart city networks. The Wi-SUN Alliance Field Area Network (FAN) primarily covers outdoor networks. The Wi-SUN FAN specification defines an IPv6-based protocol suite that includes TCP/UDP, IPv6, 6lo adaptation layer, DHCPv6 for IPv6 address management, RPL, and ICMPv6.¶
Thread is an IPv6-based networking protocol stack built on open standards, designed for smart home environments, and based on low-power IEEE Std 802.15.4 mesh networks. Because of its IPv6 foundation, Thread can support existing popular application layers and IoT platforms, provide end-to-end security, ease development, and enable flexible designs [Thread].¶
The Thread specification uses the IEEE Std 802.15.4 [IEEE-802.15.4] physical and MAC layers operating at 250 kbps in the 2.4 GHz band.¶
Thread devices use 6LoWPAN, as defined in [RFC4944] and [RFC6282], for transmission of IPv6 packets over IEEE Std 802.15.4 networks. Header compression is used within the Thread network, and devices transmitting messages compress the IPv6 header to minimize the size of the transmitted packet. The mesh header is supported for link-layer (i.e., mesh-under) forwarding. The mesh header as used in Thread also allows efficient end-to-end fragmentation of messages rather than the hop-by-hop fragmentation specified in [RFC4944]. Mesh-under routing in Thread is based on a distance vector protocol in a full mesh topology.¶
G3-PLC [G3-PLC] is a narrowband PLC technology that is based on the ITU-T G.9903 Recommendation [G.9903]. G3-PLC supports multi-hop mesh network topology and facilitates highly reliable, long-range communication. With the abilities to support IPv6 and to cross transformers, G3-PLC is regarded as one of the next-generation narrowband PLC technologies. G3-PLC has got massive deployments over several countries, e.g., Japan and France.¶
The main application domains using G3-PLC are smart grid and smart cities. This includes, but is not limited to, the following applications:¶
In the G3-PLC specification, the 6lo adaption layer utilizes the 6LoWPAN functions (e.g., header compression, fragmentation, and reassembly). However, due to the different characteristics of the PLC media, the 6LoWPAN adaptation layer cannot perfectly fulfill the requirements [RFC9354]. The ESC dispatch type is used in the G3-PLC to provide fundamental mesh routing and bootstrapping functionalities [RFC8066].¶
The Netricity program in the HomePlug Powerline Alliance [NETRICITY] promotes the adoption of products built on the IEEE Std 1901.2 low-frequency narrowband PLC standard [IEEE-1901.2], which provides for urban and long-distance communications and propagation through transformers of the distribution network using frequencies below 500 kHz. The technology also addresses requirements that assure communication privacy and secure networks.¶
The main application domains using Netricity are smart grid and smart cities. This includes, but is not limited to, the following applications:¶
The Netricity system architecture is based on the physical and MAC layers of IEEE Std 1901.2. Regarding the 6lo adaptation layer and an IPv6 network layer, Netricity utilizes IPv6 protocol suite including 6lo/6LoWPAN header compression, DHCPv6 for IP address management, RPL routing protocol, ICMPv6, and unicast/multicast forwarding. Note that the L3 routing in Netricity uses RPL in non-storing mode with the MRHOF (Minimum Rank with Hysteresis Objective Function) based on their own defined Estimated Transmission Time (ETT) metric.¶
As IPv6 stacks for constrained-node networks use a variation of the 6LoWPAN stack applied to each particular link-layer technology, various 6lo use cases can be provided. In this section, various 6lo use cases, which are based on different link-layer technologies, are described.¶
Z-Wave is one of the main technologies that may be used to enable smart home applications. Born as a proprietary technology, Z-Wave was specifically designed for this particular use case. Recently, the Z-Wave radio interface (physical and MAC layers) has been standardized as the ITU-T G.9959 specification [G.9959].¶
Example: Use of ITU-T G.9959 for Home Automation¶
A variety of home devices (e.g., light dimmers/switches, plugs, thermostats, blinds/curtains, and remote controls) are augmented with ITU-T G.9959 interfaces. A user may turn home appliances on and off, or the user may control them by pressing a wall switch or a button on a remote control. Scenes may be programmed so that the home devices adopt a specific configuration after a given event. Sensors may also periodically send measurements of several parameters (e.g., gas presence, light, temperature, humidity), which are collected at a sink device, or may generate commands for actuators (e.g., a smoke sensor may send an alarm message to a safety system).¶
The devices involved in the described scenario are nodes of a network that follows the mesh topology, which is suitable for path diversity to face indoor multipath propagation issues. The multi-hop paradigm allows end-to-end connectivity when direct range communication is not possible.¶
The key feature behind the current high Bluetooth LE momentum is its support in a large majority of smartphones in the market. Bluetooth LE can be used to allow interaction between a smartphone and surrounding sensors or actuators. Furthermore, Bluetooth LE is also the main radio interface currently available in wearables. Since a smartphone typically has several radio interfaces that provide Internet access, such as Wi-Fi or cellular, a smartphone can act as a gateway for nearby devices, such as sensors, actuators, or wearables. Bluetooth LE may be used in several domains, including healthcare, sports/wellness, and home automation.¶
Example: Use of a Body Area Network Based on Bluetooth LE for Fitness¶
A person wears a smartwatch for fitness purposes. The smartwatch has several sensors (e.g., heart rate, accelerometer, gyrometer, GPS, and temperature), a display, and a Bluetooth LE radio interface. The smartwatch can show fitness-related statistics on its display. However, when a paired smartphone is in range of the smartwatch, the latter can report almost real-time measurements of its sensors to the smartphone, which can forward the data to a cloud service on the Internet. 6lo enables this use case by providing efficient end-to-end IPv6 support. In addition, the smartwatch can receive notifications (e.g., alarm signals) from the cloud service via the smartphone. On the other hand, the smartphone may locally generate messages for the smartwatch, such as e-mail reception or calendar notifications.¶
The functionality supported by the smartwatch may be complemented by other devices, such as other on-body sensors, wireless headsets, or head-mounted displays. All such devices may connect to the smartphone, creating a star topology network whereby the smartphone is the central component. Support for extended network topologies (e.g., mesh networks) is being developed as of the writing of this document.¶
DECT is a technology widely used for wireless telephone communications in residential scenarios. Since DECT-ULE is a low-power variant of DECT, DECT-ULE can be used to connect constrained devices (such as sensors and actuators) to a Fixed Part (FP), a device that typically acts as a base station for wireless telephones. In this case, additionally, the FP must have a data network connection. Therefore, DECT-ULE is especially suitable for the connected home space in application areas such as home automation, smart metering, safety, and healthcare. Since DECT-ULE uses dedicated bandwidth, it avoids this coexistence issues suffered by other technologies that use, for example, Industrial, Scientific, and Medical (ISM) frequency bands.¶
Example: Use of DECT-ULE for Smart Metering¶
The smart electricity meter of a home is equipped with a DECT-ULE transceiver. This device is in the coverage range of the FP of the home. The FP can act as a router connected to the Internet. This way, the smart meter can transmit electricity consumption readings through the DECT-ULE link with the FP, and the latter can forward such readings to the utility company using Wide Area Network (WAN) links. The meter can also receive queries from the utility company or from an advanced energy control system controlled by the user, which may also be connected to the FP via DECT-ULE.¶
The primary use case for IPv6 over MS/TP (6LoBAC) is in building automation networks. [BACnet] is the open, international standard protocol for building automation, and MS/TP is defined in [BACnet] Clause 9. MS/TP was designed to be a low-cost, multi-drop field bus to interconnect the most numerous elements (sensors and actuators) of a building automation network to their controllers. A key aspect of 6LoBAC is that it is designed to co-exist with BACnet MS/TP on the same link, easing the ultimate transition of some BACnet networks to fundamental end-to-end IPv6 transport protocols. New applications for 6LoBAC may be found in other domains where low cost, long distance, and low latency are required. Note that BACnet comprises various networking solutions other than MS/TP, including the recently emerged BACnet IP. However, the latter is based on high-speed Ethernet infrastructure, and it is outside of the constrained-node network scope.¶
Example: Use of 6LoBAC in Building Automation Networks¶
The majority of installations for MS/TP are for "terminal" or "unitary" controllers, i.e., single zone or room controllers that may connect to HVAC or other controls such as lighting or blinds. The economics of daisy chaining a single twisted pair between multiple devices is often preferred over home-run, Cat-5-style wiring.¶
A multi-zone controller might be implemented as an IP router between a classical Ethernet link and several 6LoBAC links, fanning out to multiple terminal controllers.¶
The superior distance capabilities of MS/TP (~1 km) compared to other 6lo media may suggest its use in applications to connect remote devices to the nearest building infrastructure. For example, remote pumping or measuring stations with moderate bandwidth requirements can benefit from the low-cost and robust capabilities of MS/TP over other wired technologies such as DSL, without the line-of-sight restrictions or hop-by-hop latency of many low-cost wireless solutions.¶
In different applications, a variety of secured data can be handled and transferred. Depending on the security level of the data, different transfer methods can be alternatively selected.¶
Example: Use of NFC for Secure Transfer in Healthcare Services with Tele-Assistance¶
An older adult who lives alone wears one to several wearable 6lo devices to measure heartbeat, pulse rate, etc. Other 6lo devices are densely installed at home for movement detection. A 6LBR at home will send the sensed information to a connected healthcare center. Portable base stations with displays may be used to check the data at home, as well. Data is gathered in both periodic and event-driven fashion. In this application, event-driven data can be very time critical. In addition, privacy becomes a serious issue in this case, as the sensed data is very personal.¶
While the older adult is provided audio and video healthcare services by a tele-assistance based on cellular connections, the older adult can alternatively use NFC connections to transfer the personal sensed data to the tele-assistance. Hackers can overhear the data based on the cellular connection, but they cannot gather the personal data over the NFC connection.¶
The smart grid concept is based on deploying numerous operational and energy measuring subsystems in an electricity grid system. It comprises multiple administrative levels and segments to provide connectivity among these numerous components. Last mile connectivity is established over the Low-Voltage segment, whereas connectivity over electricity distribution takes place over the High-Voltage segment. Smart grid systems include AMI, Demand Response, Home Energy Management System, and Wide Area Situational Awareness (WASA), among others.¶
Although other wired and wireless technologies are also used in a smart grid, PLC benefits from reliable data communication over electrical power lines that are already present, and the deployment cost can be comparable to wireless technologies. The 6lo-related scenarios for PLC mainly lie in the Low-Voltage PLC networks with most applications in the area of advanced metering infrastructure, vehicle-to-grid communications, in-home energy management, and smart street lighting.¶
Example: Use of PLC for AMI¶
Household electricity meters transmit time-based data of electric power consumption through PLC. Data concentrators receive all the meter data in their corresponding living districts and send them to the Meter Data Management System through a WAN network (e.g., Medium-Voltage PLC, Ethernet, or General Packet Radio Service (GPRS)) for storage and analysis. Two-way communications are enabled, which means smart meters can perform actions like notification of electricity charges according to the commands from the utility company.¶
With the existing power line infrastructure as a communication medium, the cost of building up the PLC network is naturally saved, and more importantly, labor and operational costs can be minimized from a long-term perspective. Furthermore, this AMI application speeds up electricity charging, reduces losses by restraining power theft, and helps to manage the health of the grid based on line loss analysis.¶
Example: Use of PLC (IEEE Std 1901.1) for WASA in a Smart Grid¶
Many subsystems of a smart grid require low data rates, and narrowband variants (e.g., IEEE Std 1901.1) of PLC fulfill such requirements. Recently, more complex scenarios are emerging that require higher data rates.¶
A WASA subsystem is an appropriate example that collects large amounts of information about the current state of the grid over a wide area from electric substations as well as power transmission lines. The collected feedback is used for monitoring, controlling, and protecting all the subsystems.¶
This document has no IANA actions.¶
This document does not create security concerns in addition to those described in the Security Considerations sections of the 6lo adaptation layers considered in this document [RFC7428], [RFC7668], [RFC8105], [RFC8163], [RFC9159], [RFC9428], and [RFC9354].¶
Neighbor Discovery in 6lo links may be susceptible to threats as detailed in [RFC3756]. Mesh routing is expected to be common in some 6lo networks, such as ITU-T G.9959 networks, Bluetooth LE mesh networks, and PLC networks. This implies additional threats due to ad hoc routing as per [KW03]. Most of the L2 technologies considered in this document (i.e., ITU-T G.9959, Bluetooth LE, DECT-ULE, and PLC) support link-layer security. Making use of such provisions will alleviate the threats mentioned above. Note that NFC is often considered to offer intrinsic security properties due to its short link range. MS/TP does not support link-layer security, since in its original BACnet protocol stack, security is provided at the network layer; thus, alternative security functionality needs to be used for a 6lo-based protocol stack over MS/TP.¶
End-to-end communication is expected to be secured by means of common mechanisms, such as IPsec, DTLS/TLS, Object Security [RFC8613], and Ephemeral Diffie-Hellman Over COSE (EDHOC) [EDHOC].¶
The 6lo stack uses the IPv6 addressing model. The implications for privacy and network performance of using L2-address-derived IPv6 addresses need to be considered [RFC8065].¶
[RFC6568] lists the dimensions used to describe the design space of wireless sensor networks in the context of the 6LoWPAN Working Group. The design space is already limited by the unique characteristics of a LoWPAN (e.g., low power, short range, low bit rate). In Section 2 of [RFC6568], the following design space dimensions are described: Deployment, Network Size, Power Source, Connectivity, Multi-Hop Communication, Traffic Pattern, Mobility, and Quality of Service (QoS). However, in this document, the following design space dimensions are considered:¶
Carles Gomez has been funded in part by the Spanish Government through the Jose Castillejo CAS15/00336 grant, the TEC2016-79988-P grant, and the PID2019-106808RA-I00 grant as well as by Secretaria d'Universitats i Recerca del Departament d'Empresa i Coneixement de la Generalitat de Catalunya through grants 2017 SGR 376 and 2021 SGR 00330. His contribution to this work has been carried out in part during his stay as a visiting scholar at the Computer Laboratory of the University of Cambridge.¶
Thomas Watteyne, Pascal Thubert, Xavier Vilajosana, Daniel Migault, Jianqiang Hou, Kerry Lynn, S.V.R. Anand, and Seyed Mahdi Darroudi have provided valuable feedback for this document.¶
Das Subir and Michel Veillette have provided valuable information of jupiterMesh, and Paul Duffy has provided valuable information of Wi-SUN for this document. Also, Jianqiang Hou has provided valuable information of G3-PLC and Netricity for this document. Take Aanstoot, Kerry Lynn, and Dave Robin have provided valuable information of MS/TP and practical use case of MS/TP for this document.¶
Deoknyong Ko has provided relevant text of LTE-MTC, and he shared his experience to deploy IPv6 and 6lo technologies over LTE MTC in SK Telecom.¶