6Lo Working Group Y-G. Hong
Internet-Draft ETRI
Intended status: Informational C. Gomez
Expires: March 13, 2020 UPC
Y-H. Choi
ETRI
AR. Sangi
Huaiyin Institute of Technology
T. Aanstoot
Modio AB
S. Chakrabarti
September 10, 2019
IPv6 over Constrained Node Networks (6lo) Applicability & Use cases
draft-ietf-6lo-use-cases-07
Abstract
This document describes the applicability of IPv6 over constrained
node networks (6lo) and provides practical deployment examples. In
addition to IEEE 802.15.4, various link layer technologies such as
ITU-T G.9959 (Z-Wave), BLE, DECT-ULE, MS/TP, NFC, and PLC (IEEE
1901.2) are used as examples. The document targets an audience who
like to understand and evaluate running end-to-end IPv6 over the
constrained node networks connecting devices to each other or to
other devices on the Internet (e.g. cloud infrastructure).
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 of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on March 13, 2020.
Hong, et al. Expires March 13, 2020 [Page 1]
Internet-Draft 6lo Applicability & Use cases September 2019
Copyright Notice
Copyright (c) 2019 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 Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4
3. 6lo Link layer technologies . . . . . . . . . . . . . . . . . 4
3.1. ITU-T G.9959 . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Bluetooth LE . . . . . . . . . . . . . . . . . . . . . . 4
3.3. DECT-ULE . . . . . . . . . . . . . . . . . . . . . . . . 5
3.4. MS/TP . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.5. NFC . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.6. PLC . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.7. Comparison between 6lo Link layer technologies . . . . . 7
4. 6lo Deployment Scenarios . . . . . . . . . . . . . . . . . . 8
4.1. G3-PLC usage of 6lo in network layer . . . . . . . . . . 8
4.2. Netricity usage of 6lo in network layer . . . . . . . . . 9
5. Guidelines for adopting IPv6 stack (6lo/6LoWPAN) . . . . . . 10
6. 6lo Use Case Examples . . . . . . . . . . . . . . . . . . . . 12
6.1. Use case of ITU-T G.9959: Smart Home . . . . . . . . . . 12
6.2. Use case of Bluetooth LE: Smartphone-based Interaction . 13
6.3. Use case of DECT-ULE: Smart Home . . . . . . . . . . . . 13
6.4. Use case of MS/TP: Building Automation Networks . . . . . 14
6.5. Use case of NFC: Alternative Secure Transfer . . . . . . 15
6.6. Use case of PLC: Smart Grid . . . . . . . . . . . . . . . 15
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
8. Security Considerations . . . . . . . . . . . . . . . . . . . 16
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 16
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 17
10.1. Normative References . . . . . . . . . . . . . . . . . . 17
10.2. Informative References . . . . . . . . . . . . . . . . . 19
Appendix A. Design Space Dimensions for 6lo Deployment . . . . . 20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22
Hong, et al. Expires March 13, 2020 [Page 2]
Internet-Draft 6lo Applicability & Use cases September 2019
1. Introduction
Running IPv6 on constrained node networks has different features from
general node networks due to the characteristics of constrained node
networks such as small packet size, short link-layer address, low
bandwidth, network topology, low power, low cost, and large number of
devices [RFC4919][RFC7228]. For example, some IEEE 802.15.4 link
layers have a frame size of 127 octets and IPv6 requires the layer
below to support an MTU of 1280 bytes, therefore an appropriate
fragmentation and reassembly adaptation layer must be provided at the
layer below IPv6. Also, the limited size of IEEE 802.15.4 frame and
low energy consumption requirements make the need for header
compression. The IETF 6LoPWAN (IPv6 over Low powerWPAN) working
group published an adaptation layer for sending IPv6 packets over
IEEE 802.15.4 [RFC4944], which includes a compression format for IPv6
datagrams over IEEE 802.15.4-based networks [RFC6282], and Neighbor
Discovery Optimization for 6LoPWAN [RFC6775].
As IoT (Internet of Things) services become more popular, IPv6 over
various link layer technologies 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) have been defined at [IETF_6lo] working group.
IPv6 stacks for constrained node networks use a variation of the
6LoWPAN stack applied to each particular link layer technology.
In the 6LoPWAN working group, the [RFC6568], "Design and Application
Spaces for 6LoWPANs" was published and it describes potential
application scenarios and use cases for low-power wireless personal
area networks. Hence, this 6lo applicability document aims to
provide guidance to an audience who are new to IPv6-over-low-power
networks concept and want to assess if variance of 6LoWPAN stack
[6lo] can be applied to the constrained layer two (L2) network of
their interest. This 6lo applicability document puts together
various design space dimensions such as deployment, network size,
power source, connectivity, multi-hop communication, traffic pattern,
security level, mobility, and QoS requirements etc. In addition, it
describes a few set of 6LoPWAN application scenarios and practical
deployment as examples.
This document provides the applicability and use cases of 6lo,
considering the following aspects:
o 6lo applicability and use cases MAY be uniquely different from
those of 6LoWPAN defined for IEEE 802.15.4.
Hong, et al. Expires March 13, 2020 [Page 3]
Internet-Draft 6lo Applicability & Use cases September 2019
o It SHOULD cover various IoT related wire/wireless link layer
technologies providing practical information of such technologies.
o A general guideline on how the 6LoWPAN stack can be modified for a
given L2 technology.
o Example use cases and practical deployment examples.
2. Conventions and Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
3. 6lo Link layer technologies
3.1. ITU-T G.9959
The ITU-T G.9959 Recommendation [G.9959] targets low-power Personal
Area Networks (PANs), 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]. The ITU-T G.9959 can be used for smart home
applications.
3.2. Bluetooth LE
Bluetooth LE was introduced in Bluetooth 4.0, enhanced in Bluetooth
4.1, and developed even further in successive versions. Bluetooth
SIG has also published Internet Protocol Support Profile (IPSP). The
IPSP enables discovery of IP-enabled devices and establishment of
link-layer connection for transporting IPv6 packets. IPv6 over
Bluetooth LE is dependent on both Bluetooth 4.1 and IPSP 1.0 or
newer.
Many Devices such as mobile phones, notebooks, tablets and other
handheld computing devices which support Bluetooth 4.0 or subsequent
chipsets 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 such as phones, tablets and notebook
computers. 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
Hong, et al. Expires March 13, 2020 [Page 4]
Internet-Draft 6lo Applicability & Use cases September 2019
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 is being developed [I-D.ietf-6lo-blemesh]
3.3. DECT-ULE
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.
The DECT ULE protocol stack consists of the PHY layer operating at
frequencies in the 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 FDMA/TDMA/TDD techniques.
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 (PP) attached. The MAC layer supports
traditional DECT as this is used for services like discovery,
pairing, security features etc. All these features have been reused
from DECT.
The DECT ULE device can switch to the ULE mode of operation,
utilizing the new 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.
3.4. MS/TP
Master-Slave/Token-Passing (MS/TP) is a Medium Access Control (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: a) MS/TP devices are typically
Hong, et al. Expires March 13, 2020 [Page 5]
Internet-Draft 6lo Applicability & Use cases September 2019
mains powered, b) all MS/TP devices on a segment can communicate
directly so there are no hidden node or mesh routing issues, and c)
the latest MS/TP specification provides support for large payloads,
eliminating the need for fragmentation and reassembly below IPv6.
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
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 superior "range" (~1 km) compared to many low power
wireless data links, MS/TP may be suitable to connect remote devices
(such as district heating controllers) to the nearest building
control infrastructure over a single link [RFC8163]. MS/TP can be
used for building automation networks.
3.5. NFC
NFC technology enables simple and safe two-way interactions between
electronic devices, allowing consumers to perform contactless
transactions, access digital content, and connect electronic devices
with a single touch. NFC complements many popular consumer level
wireless technologies, by utilizing the key elements in existing
standards for contactless card technology (ISO/IEC 14443 A&B and
JIS-X 6319-4). NFC can be compatible with existing contactless card
infrastructure and it enables a consumer to utilize one device across
different systems.
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 ideal for establishing
connections with other technologies by the simplicity of touch. In
addition to the easy connection and quick transactions, simple data
sharing is also available [I-D.ietf-6lo-nfc]. NFC can be used for
secure transfer in healthcare services.
Hong, et al. Expires March 13, 2020 [Page 6]
Internet-Draft 6lo Applicability & Use cases September 2019
3.6. PLC
PLC is a data transmission technique that utilizes power conductors
as medium. Unlike other dedicated communication infrastructure,
power conductors are widely available indoors and outdoors.
Moreover, wired technologies are more susceptible to cause
interference but are more reliable than their wireless counterparts.
PLC is a data transmission technique that utilizes power conductors
as medium[I-D.ietf-6lo-plc].
The below table shows some available open standards defining PLC.
+-------------+-----------------+------------+-----------+----------+
| PLC Systems | Frequency Range | Type | Data Rate | Distance |
+-------------+-----------------+------------+-----------+----------+
| IEEE1901 | <100MHz | Broadband | 200Mbps | 1000m |
| | | | | |
| IEEE1901.1 | <15MHz | PLC-IoT | 10Mbps | 2000m |
| | | | | |
| IEEE1901.2 | <500kHz | Narrowband | 200Kbps | 3000m |
+-------------+-----------------+------------+-----------+----------+
Table 1: Some Available Open Standards in PLC
[IEEE1901] defines a broadband variant of PLC but is effective within
short range. This standard addresses the requirements of
applications with high data rate such as: Internet, HDTV, Audio,
Gaming etc. Broadband operates on OFDM (Orthogonal Frequency
Division Multiplexing) modulation.
[IEEE1901.2] defines a narrowband variant of PLC with less data rate
but significantly higher transmission range that could be used in an
indoor or even an outdoor environment. It is applicable to typical
IoT applications such as: Building Automation, Renewable Energy,
Advanced Metering, Street Lighting, Electric Vehicle, Smart Grid etc.
Moreover, IEEE 1901.2 standard is based on the 802.15.4 MAC sub-layer
and fully endorses the security scheme defined in 802.15.4 [RFC8036].
A typical use case of PLC is smart grid.
3.7. Comparison between 6lo Link layer technologies
In above clauses, various 6lo Link layer technologies and a possible
candidate are described. The following table shows that dominant
paramters of each use case corresponding to the 6lo link layer
technology.
Hong, et al. Expires March 13, 2020 [Page 7]
Internet-Draft 6lo Applicability & Use cases September 2019
+--------------+---------+---------+---------+---------+---------+---------+
| | Z-Wave | BLE | DECT-ULE| MS/TP | NFC | PLC |
+--------------+---------+---------+---------+---------+---------+---------+
| | Home | Interact| | Building| Health- | |
| Usage | Auto- | w/ Smart| Meter | Auto- | care | Smart |
| | mation | Phone | Reading | mation | Service | Grid |
+--------------+---------+---------+---------+---------+---------+---------+
| Topology | L2-mesh | Star | Star | MS/TP | P2P | Star |
| & | or | & | | | | Tree |
| Subnet | L3-mesh | Mesh | No mesh | No mesh | L2-mesh | Mesh |
+--------------+---------+---------+---------+---------+---------+---------+
| | | | | | | |
| Mobility | No | Low | No | No | Moderate| No |
| Requirement | | | | | | |
+--------------+---------+---------+---------+---------+---------+---------+
| | High + | | High + | High + | | High + |
| Security | Privacy |Partially| Privacy | Authen. | High | Encrypt.|
| Requirement | required| | required| required| | required|
+--------------+---------+---------+---------+---------+---------+---------+
| | | | | | | |
| Buffering | Low | Low | Low | Low | Low | Low |
| Requirement | | | | | | |
+--------------+---------+---------+---------+---------+---------+---------+
| Latency, | | | | | | |
| QoS | High | Low | Low | High | High | Low |
| Requirement | | | | | | |
+--------------+---------+---------+---------+---------+---------+---------+
| | | | | | | |
| Data | Infrequ-| Infrequ-| Infrequ-| Frequent| Small | Infrequ-|
| Rate | ent | ent | ent | | | ent |
+--------------+---------+---------+---------+---------+---------+---------+
| RFC # | | | | | draft- | draft- |
| or | RFC7428 | RFC7668 | RFC8105 | RFC8163 | ietf-6lo| ietf-6lo|
| Draft | | | | | -nfc | -plc |
+--------------+---------+---------+---------+---------+---------+---------+
Table 2: Comparison between 6lo Link layer technologies
4. 6lo Deployment Scenarios
4.1. G3-PLC usage of 6lo in network layer
G3-PLC [G3-PLC] is a narrow-band PLC technology that is based on
ITU-T G.9903 Recommendation [G.9903]. G3-PLC supports multi-hop mesh
network, 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 NB-PLC technologies.
Hong, et al. Expires March 13, 2020 [Page 8]
Internet-Draft 6lo Applicability & Use cases September 2019
G3-PLC has got massive deployments over several countries, e.g.
Japan and France.
The main application domains targeted by G3-PLC are smart grid and
smart cities. This includes, but is not limited to the following
applications:
o Smart Metering
o Vehicle-to-Grid Communication
o Demand Response (DR)
o Distribution Automation
o Home/Building Energy Management Systems
o Smart Street Lighting
o Advanced Metering Infrastructure (AMI) backbone network
o Wind/Solar Farm Monitoring
In the G3-PLC specification, the 6lo adaptation layer utilizes the
6LoWPAN functions (e.g. header compression, fragmentation and
reassembly) so as to enable IPv6 packet transmission. LOADng, which
is a lightweight variant of AODV, is applied as the mesh-under
routing protocol in G3-PLC networks. Address assignment and network
configuration are based on the bootstrapping protocol specified in
ITU-T G.9903. The network layer consists of IPv6 and ICMPv6 while
the transport protocol UDP is used for data transmission.
4.2. Netricity usage of 6lo in network layer
The Netricity program in HomePlug Powerline Alliance [NETRICITY]
promotes the adoption of products built on the IEEE 1901.2 Low-
Frequency Narrow-Band PLC standard, 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 targeted by Netricity are smart grid and
smart cities. This includes, but is not limited to the following
applications:
o Utility grid modernization
Hong, et al. Expires March 13, 2020 [Page 9]
Internet-Draft 6lo Applicability & Use cases September 2019
o Distribution automation
o Meter-to-Grid connectivity
o Micro-grids
o Grid sensor communications
o Load control
o Demand response
o Net metering
o Street Lighting control
o Photovoltaic panel monitoring
Netricity system architecture is based on the PHY and MAC layers of
IEEE 1901.2 PLC standard. Regarding the 6lo adaptation layer and
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 layer 3 routing in Netricity uses RPL in non-storing mode
with the MRHOF objective function based on the own defined Estimated
Transmission Time (ETT) metric.
5. Guidelines for adopting IPv6 stack (6lo/6LoWPAN)
The following guideline targets new candidate constrained L2
technologies that may be considered for running modified 6LoWPAN
stack on top. The modification of 6LoWPAN stack should be based on
the following:
o Addressing Model: Addressing model determines whether the device
is capable of forming IPv6 Link-local and global addresses and
what is the best way to derive the IPv6 addresses for the
constrained L2 devices. Whether the device is capable of forming
IPv6 Link-local and global addresses, L2-address-derived IPv6
addresses are specified in [RFC4944], but there exist implications
for privacy. For global usage, a unique IPv6 address must be
derived using an assigned prefix and a unique interface ID.
[RFC8065] provides such guidelines. For MAC derived IPv6 address,
please refer to [RFC8163] for IPv6 address mapping examples.
Broadcast and multicast support are dependent on the L2 networks.
Most low-power L2 implementations map multicast to broadcast
networks. So care must be taken in the design when to use
broadcast and try to stick to unicast messaging whenever possible.
Hong, et al. Expires March 13, 2020 [Page 10]
Internet-Draft 6lo Applicability & Use cases September 2019
o MTU Considerations: The deployment SHOULD consider their need for
maximum transmission unit (MTU) of a packet over the link layer
and should consider if fragmentation and reassembly of packets are
needed at the 6LoWPAN layer. For example, if the link layer
supports fragmentation and reassembly of packets, then 6LoWPAN
layer may skip supporting fragmentation/reassembly. In fact, for
most efficiency, choosing a low-power link layer that can carry
unfragmented application packets would be optimum for packet
transmission if the deployment can afford it. Please refer to 6lo
RFCs [RFC7668], [RFC8163], [RFC8105] for example guidance.
o Mesh or L3-Routing: 6LoWPAN specifications do provide mechanisms
to support for mesh routing at L2. [RFC6550] defines layer three
(L3) routing for low power lossy networks using directed graphs.
6LoWPAN is routing protocol agnostic and other L2 or L3 routing
protocols can be run using a 6LoWPAN stack.
o Address Assignment: 6LoWPAN requires that IPv6 Neighbor Discovery
for low power networks [RFC6775] be used for autoconfiguration of
stateless IPv6 address assignment. Considering the energy
sensitive networks [RFC6775] makes optimization from classical
IPv6 ND [RFC4861] protocol. It is the responsibility of the
deployment to ensure unique global IPv6 addresses for the Internet
connectivity. For local-only connectivity IPv6 ULA may be used.
[RFC6775] specifies the 6LoWPAN border router(6LBR) which is
responsible for prefix assignment to the 6lo/6LoWPAN network. 6LBR
can be connected to the Internet or Enterprise network via its one
of the interfaces. Please refer to [RFC7668] and [RFC8105] for
examples of address assignment considerations. In addition,
privacy considerations [RFC8065] must be consulted for
applicability. In certain scenarios, the deployment may not
support autoconfiguration of IPv6 addressing due to regulatory and
business reasons and may choose to offer a separate address
assignment service.
o Header Compression: IPv6 header compression [RFC6282] is a vital
part of IPv6 over low power communication. Examples of header
compression for different link-layers specifications are found in
[RFC7668], [RFC8163], [RFC8105]. A generic header compression
technique is specified in [RFC7400].
o Security and Encryption: Though 6LoWPAN basic specifications do
not address security at the network layer, the assumption is that
L2 security must be present. In addition, application level
security is highly desirable. The working groups [ace] and [core]
should be consulted for application and transport level security.
6lo working group is working on address authentication [6lo-ap-nd]
and secure bootstrapping is also being discussed at IETF.
Hong, et al. Expires March 13, 2020 [Page 11]
Internet-Draft 6lo Applicability & Use cases September 2019
However, there may be different levels of security available in a
deployment through other standards such as hardware level security
or certificates for initial booting process. Encryption is
important if the implementation can afford it.
o Additional processing: [RFC8066] defines guidelines for ESC
dispatch octets use in the 6LoWPAN header. An implementation may
take advantage of ESC header to offer a deployment specific
processing of 6LoWPAN packets.
6. 6lo Use Case Examples
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 clause, various 6lo
use cases which are based on each particular link layer technology
are described.
6.1. Use case of ITU-T G.9959: Smart Home
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.
Example: Use of ITU-T G.9959 for Home Automation
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 on/off or may control home
appliances by pressing a wall switch or by pressing a button in a
remote control. Scenes may be programmed, so that after a given
event, the home devices adopt a specific configuration. Sensors may
also periodically send measurements of several parameters (e.g. gas
presence, light, temperature, humidity, etc.) 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 multihop paradigm
allows end-to-end connectivity when direct range communication is not
possible. Security support is required, specially for safety-related
communication. When a user interaction (e.g. a button press)
triggers a message that encapsulates a command, if the message is
lost, the user may have to perform further interactions to achieve
the desired effect (e.g. a light is turned off). A reaction to a
Hong, et al. Expires March 13, 2020 [Page 12]
Internet-Draft 6lo Applicability & Use cases September 2019
user interaction will be perceived by the user as immediate as long
as the reaction takes place within 0.5 seconds [RFC5826].
6.2. Use case of Bluetooth LE: Smartphone-based Interaction
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 the interaction between the 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 4G, the 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 Bluetooth LE-based Body Area Network for fitness
A person wears a smartwatch for fitness purposes. The smartwatch has
several sensors (e.g. heart rate, accelerometer, gyrometer, GPS,
temperature, etc.), 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 the 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. 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.
6.3. Use case of DECT-ULE: Smart Home
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, a device that
typically acts as a base station for wireless telephones. Therefore,
DECT-ULE is specially suitable for the connected home space in
application areas such as home automation, smart metering, safety,
healthcare, etc.
Hong, et al. Expires March 13, 2020 [Page 13]
Internet-Draft 6lo Applicability & Use cases September 2019
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 Fixed Part
of the home. The Fixed Part 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 Fixed Part,
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 Fixed Part
via DECT-ULE.
6.4. Use case of MS/TP: Building Automation Networks
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 inter-connect 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
native 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.
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 traditional 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, and without the line-of-site
restrictions or hop-by-hop latency of many low cost wireless
solutions.
Hong, et al. Expires March 13, 2020 [Page 14]
Internet-Draft 6lo Applicability & Use cases September 2019
6.5. Use case of NFC: Alternative Secure Transfer
According to applications, various secured data can be handled and
transferred. Depending on security level of the data, methods for
transfer can be alternatively selected.
Example: Use of NFC for Secure Transfer in Healthcare Services with
Tele-Assistance
A senior citizen who lives alone wears one to several wearable 6lo
devices to measure heartbeat, pulse rate, etc. The 6lo devices are
densely installed at home for movement detection. An LoWPAN Border
Router (LBR) at home will send the sensed information to a connected
healthcare center. Portable base stations with LCDs 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 also becomes a serious
issue in this case, as the sensed data is very personal.
While the senior citizen is provided audio and video healthcare
services by a tele-assistance based on LTE connections, the senior
citizen can alternatively use NFC connections to transfer the
personal sensed data to the tele-assistance. At this moment, hidden
hackers can overhear the data based on the LTE connection, but they
cannot gather the personal data over the NFC connection.
6.6. Use case of PLC: Smart Grid
Smart grid concept is based on numerous operational and energy
measuring sub-systems of an electric grid. It comprises of multiple
administrative levels/segments to provide connectivity among these
numerous components. Last mile connectivity is established over LV
segment, whereas connectivity over electricity distribution takes
place in HV segment.
Although other wired and wireless technologies are also used in Smart
Grid (Advance Metering Infrastructure - AMI, Demand Response - DR,
Home Energy Management System - HEMS, Wide Area Situational Awareness
- WASA etc), PLC enjoys the advantage of existing (power conductor)
medium and better reliable data communication. PLC is a promising
wired communication technology in that the electrical power lines are
already there and the deployment cost can be comparable to wireless
technologies. The 6lo related scenarios 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 Advanced Metering Infrastructure
Hong, et al. Expires March 13, 2020 [Page 15]
Internet-Draft 6lo Applicability & Use cases September 2019
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 (MDMS) through WAN network (e.g.
Medium-Voltage PLC, Ethernet or GPRS) for storage and analysis. Two-
way communications are enabled which means smart meters can do
actions like notification of electricity charges according to the
commands from the utility company.
With the existing power line infrastructure as communication medium,
cost on building up the PLC network is naturally saved, and more
importantly, labor operational costs can be minimized from a long-
term perspective. Furthermore, this AMI application speeds up
electricity charge, reduces losses by restraining power theft and
helps to manage the health of the grid based on line loss analysis.
Example: Use of PLC (IEEE1901.1) for WASA in Smart Grid
Many sub-systems of Smart Grid require low data rate and narrowband
variant (IEEE1901.2) of PLC fulfils such requirements. Recently,
more complex scenarios are emerging that require higher data rates.
WASA sub-system is an appropriate example that collects large amount
of information about the current state of the grid over wide area
from electric substations as well as power transmission lines. The
collected feedback is used for monitoring, controlling and protecting
all the sub-systems.
7. IANA Considerations
There are no IANA considerations related to this document.
8. Security Considerations
Security considerations are not directly applicable to this document.
The use cases will use the security requirements described in the
protocol specifications.
9. Acknowledgements
Carles Gomez has been funded in part by the Spanish Government
through the Jose Castillejo CAS15/00336 grant, and through the
TEC2016-79988-P grant. 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,
and Jianqiang HOU have provided valuable feedback for this draft.
Hong, et al. Expires March 13, 2020 [Page 16]
Internet-Draft 6lo Applicability & Use cases September 2019
Das Subir and Michel Veillette have provided valuable information of
jupiterMesh and Paul Duffy has provided valuable information of Wi-
SUN for this draft. Also, Jianqiang Hou has provided valuable
information of G3-PLC and Netricity for this draft. Kerry Lynn and
Dave Robin have provided valuable information of MS/TP and practical
use case of MS/TP for this draft.
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.
10. References
10.1. Normative References
[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>.
[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>.
[RFC5826] Brandt, A., Buron, J., and G. Porcu, "Home Automation
Routing Requirements in Low-Power and Lossy Networks",
RFC 5826, DOI 10.17487/RFC5826, April 2010,
<https://www.rfc-editor.org/info/rfc5826>.
[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>.
[RFC6550] Winter, T., Ed., Thubert, P., Ed., Brandt, A., Hui, J.,
Kelsey, R., Levis, P., Pister, K., Struik, R., Vasseur,
JP., and R. Alexander, "RPL: IPv6 Routing Protocol for
Low-Power and Lossy Networks", RFC 6550,
DOI 10.17487/RFC6550, March 2012,
<https://www.rfc-editor.org/info/rfc6550>.
Hong, et al. Expires March 13, 2020 [Page 17]
Internet-Draft 6lo Applicability & Use cases September 2019
[RFC6568] Kim, E., Kaspar, D., and JP. Vasseur, "Design and
Application Spaces for IPv6 over Low-Power Wireless
Personal Area Networks (6LoWPANs)", RFC 6568,
DOI 10.17487/RFC6568, April 2012,
<https://www.rfc-editor.org/info/rfc6568>.
[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>.
[RFC7228] Bormann, C., Ersue, M., and A. Keranen, "Terminology for
Constrained-Node Networks", RFC 7228,
DOI 10.17487/RFC7228, May 2014,
<https://www.rfc-editor.org/info/rfc7228>.
[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>.
[RFC7428] Brandt, A. and J. Buron, "Transmission of IPv6 Packets
over ITU-T G.9959 Networks", RFC 7428,
DOI 10.17487/RFC7428, February 2015,
<https://www.rfc-editor.org/info/rfc7428>.
[RFC7668] Nieminen, J., Savolainen, T., Isomaki, M., Patil, B.,
Shelby, Z., and C. Gomez, "IPv6 over BLUETOOTH(R) Low
Energy", RFC 7668, DOI 10.17487/RFC7668, October 2015,
<https://www.rfc-editor.org/info/rfc7668>.
[RFC8036] Cam-Winget, N., Ed., Hui, J., and D. Popa, "Applicability
Statement for the Routing Protocol for Low-Power and Lossy
Networks (RPL) in Advanced Metering Infrastructure (AMI)
Networks", RFC 8036, DOI 10.17487/RFC8036, January 2017,
<https://www.rfc-editor.org/info/rfc8036>.
[RFC8065] Thaler, D., "Privacy Considerations for IPv6 Adaptation-
Layer Mechanisms", RFC 8065, DOI 10.17487/RFC8065,
February 2017, <https://www.rfc-editor.org/info/rfc8065>.
[RFC8066] Chakrabarti, S., Montenegro, G., Droms, R., and J.
Woodyatt, "IPv6 over Low-Power Wireless Personal Area
Network (6LoWPAN) ESC Dispatch Code Points and
Guidelines", RFC 8066, DOI 10.17487/RFC8066, February
2017, <https://www.rfc-editor.org/info/rfc8066>.
Hong, et al. Expires March 13, 2020 [Page 18]
Internet-Draft 6lo Applicability & Use cases September 2019
[RFC8105] Mariager, P., Petersen, J., Ed., Shelby, Z., Van de Logt,
M., and D. Barthel, "Transmission of IPv6 Packets over
Digital Enhanced Cordless Telecommunications (DECT) Ultra
Low Energy (ULE)", RFC 8105, DOI 10.17487/RFC8105, May
2017, <https://www.rfc-editor.org/info/rfc8105>.
[RFC8163] Lynn, K., Ed., Martocci, J., Neilson, C., and S.
Donaldson, "Transmission of IPv6 over Master-Slave/Token-
Passing (MS/TP) Networks", RFC 8163, DOI 10.17487/RFC8163,
May 2017, <https://www.rfc-editor.org/info/rfc8163>.
[RFC8352] Gomez, C., Kovatsch, M., Tian, H., and Z. Cao, Ed.,
"Energy-Efficient Features of Internet of Things
Protocols", RFC 8352, DOI 10.17487/RFC8352, April 2018,
<https://www.rfc-editor.org/info/rfc8352>.
10.2. Informative References
[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>.
[I-D.ietf-6lo-nfc]
Choi, Y., Hong, Y., Youn, J., Kim, D., and J. Choi,
"Transmission of IPv6 Packets over Near Field
Communication", draft-ietf-6lo-nfc-15 (work in progress),
July 2019.
[I-D.ietf-6lo-blemesh]
Gomez, C., Darroudi, S., Savolainen, T., and M. Spoerk,
"IPv6 Mesh over BLUETOOTH(R) Low Energy using IPSP",
draft-ietf-6lo-blemesh-05 (work in progress), March 2019.
[I-D.ietf-6lo-plc]
Hou, J., Liu, B., Hong, Y., Tang, X., and C. Perkins,
"Transmission of IPv6 Packets over PLC Networks", draft-
ietf-6lo-plc-00 (work in progress), February 2019.
[IETF_6lo]
"IETF IPv6 over Networks of Resource-constrained Nodes
(6lo) working group",
<https://datatracker.ietf.org/wg/6lo/charter/>.
Hong, et al. Expires March 13, 2020 [Page 19]
Internet-Draft 6lo Applicability & Use cases September 2019
[TIA-485-A]
"TIA, "Electrical Characteristics of Generators and
Receivers for Use in Balanced Digital Multipoint Systems",
TIA-485-A (Revision of TIA-485)", March 2003,
<https://global.ihs.com/
doc_detail.cfm?item_s_key=00032964>.
[G3-PLC] "G3-PLC Alliance", <http://www.g3-plc.com/home/>.
[NETRICITY]
"Netricity program in HomePlug Powerline Alliance",
<http://groups.homeplug.org/tech/Netricity>.
[G.9959] "International Telecommunication Union, "Short range
narrow-band digital radiocommunication transceivers - PHY
and MAC layer specifications", ITU-T Recommendation",
January 2015.
[G.9903] "International Telecommunication Union, "Narrowband
orthogonal frequency division multiplexing power line
communication transceivers for G3-PLC networks", ITU-T
Recommendation", August 2017.
[IEEE1901]
"IEEE Standard, IEEE Std. 1901-2010 - IEEE Standard for
Broadband over Power Line Networks: Medium Access Control
and Physical Layer Specifications", 2010,
<https://standards.ieee.org/findstds/
standard/1901-2010.html>.
[IEEE1901.2]
"IEEE Standard, IEEE Std. 1901.2-2013 - IEEE Standard for
Low-Frequency (less than 500 kHz) Narrowband Power Line
Communications for Smart Grid Applications", 2013,
<https://standards.ieee.org/findstds/
standard/1901.2-2013.html>.
[BACnet] "ASHRAE, "BACnet-A Data Communication Protocol for
Building Automation and Control Networks", ANSI/ASHRAE
Standard 135-2016", January 2016,
<http://www.techstreet.com/ashrae/standards/ashrae-
135-2016?product_id=1918140#jumps>.
Appendix A. Design Space Dimensions for 6lo Deployment
The [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
Hong, et al. Expires March 13, 2020 [Page 20]
Internet-Draft 6lo Applicability & Use cases September 2019
characteristics of a LoWPAN (e.g. low power, short range, low bit
rate). In [RFC6568], the following design space dimensions are
described: Deployment, Network size, Power source, Connectivity,
Multi-hop communication, Traffic pattern, Mobility, Quality of
Service (QoS). However, in this document, the following design space
dimensions are considered:
o Deployment/Bootstrapping: 6lo nodes can be connected randomly, or
in an organized manner. The bootstrapping has different
characteristics for each link layer technology.
o Topology: Topology of 6lo networks may inherently follow the
characteristics of each link layer technology. Point-to-point,
star, tree or mesh topologies can be configured, depending on the
link layer technology considered.
o L2-Mesh or L3-Mesh: L2-mesh and L3-mesh may inherently follow the
characteristics of each link layer technology. Some link layer
technologies may support L2-mesh and some may not support.
o Multi-link subnet, single subnet: The selection of multi-link
subnet and single subnet depends on connectivity and the number of
6lo nodes.
o Data rate: Typically, the link layer technologies of 6lo have low
rate of data transmission. But, by adjusting the MTU, it can
deliver higher upper layer data rate.
o Buffering requirements: Some 6lo use case may require more data
rate than the link layer technology support. In this case, a
buffering mechanism to manage the data is required.
o Security and Privacy Requirements: Some 6lo use case can involve
transferring some important and personal data between 6lo nodes.
In this case, high-level security support is required.
o Mobility across 6lo networks and subnets: The movement of 6lo
nodes depends on the 6lo use case. If the 6lo nodes can move or
moved around, a mobility management mechanism is required.
o Time synchronization requirements: The requirement of time
synchronization of the upper layer service is dependent on the 6lo
use case. For some 6lo use case related to health service, the
measured data must be recorded with exact time and must be
transferred with time synchronization.
o Reliability and QoS: Some 6lo use case requires high reliability,
for example real-time service or health-related services.
Hong, et al. Expires March 13, 2020 [Page 21]
Internet-Draft 6lo Applicability & Use cases September 2019
o Traffic patterns: 6lo use cases may involve various traffic
patterns. For example, some 6lo use case may require short data
length and random transmission. Some 6lo use case may require
continuous data and periodic data transmission.
o Security Bootstrapping: Without the external operations, 6lo nodes
must have the security bootstrapping mechanism.
o Power use strategy: to enable certain use cases, there may be
requirements on the class of energy availability and the strategy
followed for using power for communication [RFC7228]. Each link
layer technology defines a particular power use strategy which may
be tuned [RFC8352]. Readers are expected to be familiar with
[RFC7228] terminology.
o Update firmware requirements: Most 6lo use cases will need a
mechanism for updating firmware. In these cases support for over
the air updates are required, probably in a broadcast mode when
bandwith is low and the number of identical devices is high.
o Wired vs. Wireless: Plenty of 6lo link layer technologies are
wireless, except MS/TP and PLC. The selection of wired or
wireless link layer technology is mainly dependent on the
requirement of 6lo use cases and the characteristics of wired/
wireless technologies. For example, some 6lo use cases may
require easy and quick deployment, whereas others may need a
continuous source of power.
Authors' Addresses
Yong-Geun Hong
ETRI
161 Gajeong-Dong Yuseung-Gu
Daejeon 305-700
Korea
Phone: +82 42 860 6557
Email: yghong@etri.re.kr
Carles Gomez
Universitat Politecnica de Catalunya/Fundacio i2cat
C/Esteve Terradas, 7
Castelldefels 08860
Spain
Email: carlesgo@entel.upc.edu
Hong, et al. Expires March 13, 2020 [Page 22]
Internet-Draft 6lo Applicability & Use cases September 2019
Younghwan Choi
ETRI
218 Gajeongno, Yuseong
Daejeon 305-700
Korea
Phone: +82 42 860 1429
Email: yhc@etri.re.kr
Abdur Rashid Sangi
Huaiyin Institute of Technology
No.89 North Beijing Road, Qinghe District
Huaian 223001
P.R. China
Email: sangi_bahrian@yahoo.com
Take Aanstoot
Modio AB
S:t Larsgatan 15, 582 24
Linkoping
Sweden
Email: take@modio.se
Samita Chakrabarti
San Jose, CA
USA
Email: samitac.ietf@gmail.com
Hong, et al. Expires March 13, 2020 [Page 23]