6lo Y. Choi, Ed.
Internet-Draft ETRI
Intended status: Standards Track C-M. Kim
Expires: 2 September 2025 KETI
C. Gomez
Universitat Politecnica de Catalunya
1 March 2025
Transmission of IPv6 Packets over Short-Range Optical Wireless
Communications
draft-ietf-6lo-owc-03
Abstract
IEEE 802.15.7, "Short-Range Optical Wireless Communications" defines
wireless communication using visible light. It defines how data is
transmitted, modulated, and organized in order to enable reliable and
efficient communication in various environments. The standard is
designed to work alongside other wireless communication systems and
supports both Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS)
communications. However, ambient light interference from natural
sunlight or artificial lighting sources can impact signal
reliability. To mitigate this, advanced modulation techniques,
optical filtering, and adaptive power control can be employed. This
document describes how IPv6 is transmitted over short-range optical
wireless communications (OWC) using 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 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 2 September 2025.
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Copyright Notice
Copyright (c) 2025 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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4
3. Short-Range Optical Wireless Communications . . . . . . . . . 5
3.1. Network Topologies . . . . . . . . . . . . . . . . . . . 5
3.2. Protocol Stack of OWC . . . . . . . . . . . . . . . . . . 6
3.3. Addressing of OWC Devices . . . . . . . . . . . . . . . . 7
3.4. MTU and data rates of OWC Link Layer . . . . . . . . . . 7
4. Specification of IPv6 over OWC . . . . . . . . . . . . . . . 7
4.1. Protocol Stack . . . . . . . . . . . . . . . . . . . . . 7
4.2. Stateless Address Autoconfiguration . . . . . . . . . . . 8
4.3. IPv6 Link-Local Address . . . . . . . . . . . . . . . . . 9
4.4. Neighbor Discovery . . . . . . . . . . . . . . . . . . . 9
4.5. Header Compression . . . . . . . . . . . . . . . . . . . 9
4.5.1. Traditional 6LoWPAN header compression . . . . . . . 10
4.5.2. SCHC header compression . . . . . . . . . . . . . . . 10
4.6. Fragmentation and Reassembly Considerations . . . . . . . 11
4.7. Unicast and Multicast Address Mapping . . . . . . . . . . 12
5. Internet Connectivity Scenarios . . . . . . . . . . . . . . . 13
5.1. OWC Device Network Connected to the Internet . . . . . . 13
5.2. OWC Device Multi-hop Network . . . . . . . . . . . . . . 14
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
7. Security Considerations . . . . . . . . . . . . . . . . . . . 15
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
8.1. Normative References . . . . . . . . . . . . . . . . . . 15
8.2. Informative References . . . . . . . . . . . . . . . . . 16
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Introduction
The rapid growth of the Internet of Things (IoT) has led to a
significant increase in the number of wireless communication
technologies utilized for real-time data collection and monitoring in
various industrial domains, such as manufacturing, agriculture,
healthcare, transportation, and so on. This trend highlights the
importance of wireless communication in facilitating real-time data
exchange and analysis, ultimately contributing to enhanced
operational efficiency and decision-making processes across different
industrial sectors.
Optical Wireless Communications (OWC) stands as one of the potential
candidates for IoT wireless communication technologies, extensively
applied across various industrial domains. The [IEEE802.15.7]
standard outlines the procedures for establishing bidirectional
communications between two OWC devices. Furthermore, IEEE 802.15.7
delineates a comprehensive OWC standard, encompassing features like
Visible Light Communication (VLC), Short-Range Communication, Line-
of-Sight (LOS) and Non-Line-of-Sight (NLOS) Support, High and Low
Data Rates, Energy Efficiency, and Secure Communication. In
addition, the standard has evolved through subsequent related
developments to address emerging application requirements:
* [IEEE802.15.7a] introduces Optical Camera Communications (OCC),
utilizing image sensors for data reception, making OWC applicable
to smart city applications and enhanced vehicular communication.
* [IEEE802.15.13-2023] was developed for industrial IoT and includes
new PHYs with pulse modulation (OOK/FDE) and adaptive OFDM for
factory automation and real-time industrial networking.
* [IEEE802.11bb-2023] extends Wi-Fi technology to optical
communication, leveraging the existing 802.11 MAC and PHY layers.
This enables seamless integration of OWC into mainstream wireless
networks, opening new possibilities for high-speed data
transmission in indoor environments.
OWC is immune to Radio Frequency (RF) interference, making it highly
suitable for environments such as hospitals, airplanes, and
industrial facilities, where RF interference is a concern.
Additionally, OWC can leverage existing visible light infrastructure,
reducing deployment costs for smart lighting and IoT applications.
OWC also provides energy-efficient operation. Nevertheless, OWC
performance is affected in Non-Line-of-Sight (NLoS) links, and by
interference produced by ambient light sources.
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OWC supports various network topologies, including peer-to-peer and
star configurations. With IPv6 over OWC, it is possible to extend
the network topology to include the mesh topology by using a route-
over mechanism. However, IPv6 over OWC needs 6LoWPAN technologies
[RFC4944] [RFC6282] [RFC6775] [RFC8505] because of the low bit rates,
limited frame size and energy constraints of OWC. Implementing
header compression (e.g., 6LoWPAN or SCHC) significantly reduces
packet size, lowering transmission power requirements and extending
battery life for IoT devices. This makes OWC a viable alternative
for low-power wireless communication in energy-constrained
environments.
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 Stateless Address
Autoconfiguration" [RFC2462], "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], and "SCHC: Generic Framework for Static Context Header
Compression and Fragmentation" [RFC8724].
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), as well as forward and route IPv6 packets. 6LoWPAN Routers
are present only in route-over topologies.
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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 that provides the prefix(es) for
the isolated network.
Duplicate Address Detection (DAD):
A mechanism used in IPv6 networks to ensure that no two devices
share the same address, preventing address conflicts.
Static Context Header Compression and fragmentation (SCHC):
Static Context Header Compression and fragmentation (SCHC), a
generic framework.
3. Short-Range Optical Wireless Communications
Optical Wireless Communication (OWC) utilizes intensity modulation of
optical sources, such as Light Emitting Diodes (LEDs) and Laser
Diodes (LDs), to transmit data at speeds faster than what the human
eye can perceive. OWC combines lighting and data communications,
finding applications in various domains including area lighting,
signboards, streetlights, vehicles, traffic signals, displays, LED
panels, and digital signage.
IEEE802.15.7 describes the use of OWC for optical wireless personal
area networks (OWPANs) and covers topics such as network topologies,
addressing, collision avoidance, acknowledgment, performance quality
indication, dimming support, visibility support, colored status
indication, and color stabilization.
3.1. Network Topologies
The MAC layer of OWC provides three types of topologies: peer-to-
peer, star and broadcast. In the star topology, the communication is
established between devices and a single central controller, called
the coordinator. In the peer-to-peer topology, one of the two
devices in an association takes on the role of the coordinator. More
complex topologies, such as the mesh topology, can be supported by
using peer-to-peer at the higher layer with IPv6 over OWC.
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3.2. Protocol Stack of OWC
IEEE 802.15.7 defines a protocol stack in terms of a number of layers
and sublayers, depicted in Figure 1. The Physical Layer (PHY) in
OWCs comprises the light transceiver and its associated low-level
control mechanisms. It handles the transmission and reception of
light signals, encoding and decoding data, and managing the physical
characteristics of the communication channel. On top of the PHY,
there is a Media Access Control (MAC) sublayer that facilitates
access to the physical channel for various types of data transfers.
The MAC sublayer controls how devices share the medium, manages
access protocols, and ensures fair and efficient utilization of the
optical wireless communication channel. The PHY and MAC sublayer
form the data link layer in optical wireless communications, enabling
the transmission and reception of data over the physical medium.
The upper layers, depicted in Figure 1, include the network layer
responsible for network configuration, manipulation, and message
routing, as well as the application layer which encompasses the
intended functionality of the device. In order to access the MAC
sublayer, a logical link control (LLC) layer can utilize the service-
specific convergence sublayer (SSCS). The LLC layer provides a
bridge between the upper layers and the MAC sublayer, facilitating
the transfer of data and control information between the two layers.
The upper layers, including the network layer and application layer,
work in conjunction with the MAC sublayer and utilize the LLC layer
and SSCS to enable efficient communication and functionality within
the optical wireless communication system.
+----------------------------------------+ - - - - - - - - - -
| Logical Link Control (LLC) Sublayer |
+----------------------------------------+
| Service-Specific Convergence Sublayer | OWC Link Layer
+----------------------------------------+
| MAC Sublayer |
+----------------------------------------+ - - - - - - - - - -
| Physical Layer | OWC Physical Layer
+----------------------------------------+ - - - - - - - - - -
Figure 1: Protocol Stack of OWC
In order to send an IPv6 packet over OWC, the packet MUST be passed
down to the LLC sublayer. For IPv6 addressing or address
configuration, the LLC sublayer MUST provide related information,
such as link-layer addresses, to its upper layer.
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3.3. Addressing of OWC Devices
OWC devices have a unique 64-bit address. When a device associates
with a coordinator node it is allowed to be allocated a short 16-bit
address. Either address is allowed to be used for communication
within the OWC data link network. Therefore, both of the 16-bit and
64-bit addresses can be used to generate an IPv6 Interface Identifier
(IID).
3.4. MTU and data rates of OWC Link Layer
+======+==============+=========================+
| Type | MTU | Data Rates |
+======+==============+=========================+
| PHY1 | 1,023 bytes | 11.67 kbps ~ 266.6 kbps |
+------+--------------+-------------------------+
| PHY2 | 65,535 bytes | 1.25 Mbps ~ 96 Mbps |
+------+--------------+-------------------------+
| PHY3 | 65,535 bytes | 12 Mbps ~ 96 Mbps |
+------+--------------+-------------------------+
Table 1: MTU and Data Rates of IEEE 802.15.7
Table 1 summarizes the maximum packet size is given by the OWC
parameter "aMaxPHYFrame-Size", and the data rate that can be
supported for each OWC PHY type, as specified in the IEEE 802.15.7.
4. Specification of IPv6 over OWC
OWC technology has requirements owing to low power consumption and
allowed protocol overhead. 6LoWPAN standards [RFC4944][RFC6775]
[RFC6282] provide useful functionality for reducing the overhead of
IPv6 over OWC. This functionality consists of link-local IPv6
addresses and stateless IPv6 address autoconfiguration (see Sections
4.2 and 4.3), Neighbor Discovery (see Section 4.4), header
compression (see Section 4.5) and and fragmentation (see
Section 4.6).
4.1. Protocol Stack
Figure 2 illustrates the IPv6-over-OWC protocol stack. Upper-layer
protocols can be transport-layer protocols (e.g., TCP and UDP),
application-layer protocols, and other protocols capable of running
on top of IPv6.
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+----------------------------------------+
| Upper-Layer Protocols |
+----------------------------------------+
| IPv6 |
+----------------------------------------+
| Adaptation Layer for IPv6 over OWC |
+----------------------------------------+
| OWC Logical Link Layer |
+----------------------------------------+
| OWC Physical Layer |
+----------------------------------------+
Figure 2: Protocol Stack for IPv6 over OWC
The Adaptation Layer for IPv6 over OWC supports Neighbor Discovery,
stateless address autoconfiguration, header compression, and
fragmentation and reassembly, based on 6LoWPAN. Note that 6LoWPAN
header compression [RFC6282] does not define header compression for
TCP. The latter can still be supported by IPv6 over OWC, albeit
without the performance optimization of header compression.
4.2. Stateless Address Autoconfiguration
An OWC device performs stateless address autoconfiguration as per
[RFC4862]. A 64-bit IID for an OWC interface is formed by utilizing
the 16-bit or 64-bit address (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 because each data
link connection is uniquely identified by OWC Data Link Layer.
Following the guidance of [RFC7136], IIDs of all unicast addresses
for OWC devices are 64 bits long and constructed by using the
generation algorithm of random identifiers (RIDs) that are stable
[RFC7217].
The RID is an output created by the F() algorithm with input
parameters. One of the parameters is Net_Iface, and the OWC 16-bit
Link-Layer Address MUST be a source of the Net_Iface parameter. The
16-bit address can easily be targeted by attacks from a third party
(e.g., address scanning). The F() algorithm with SHA-256 can provide
secured and stable IIDs for OWC devices. In addition, an optional
parameter, Network_ID, is used to increase the randomness of the
generated IID with the OWC Link-Layer Address. The secret key SHOULD
be at least 128 bits. It MUST be initialized to a pseudorandom
number [RFC4086].
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4.3. IPv6 Link-Local Address
The IPv6 Link-Local Address for an OWC device is formed by appending
the IID to the prefix fe80::/64, as depicted in Figure 3.
0 0 0 1
0 1 6 2
0 0 4 7
+----------+------------------+----------------------------+
|1111111010| zeros | Interface Identifier |
+----------+------------------+----------------------------+
. .
. <- - - - - - - - - - - 128 bits - - - - - - - - - - - -> .
. .
Figure 3: IPv6 Link-Local Address in OWC
4.4. Neighbor Discovery
Neighbor Discovery Optimization for 6LoWPANs [RFC6775][RFC8505]
describes the Neighbor Discovery approach in several 6LoWPAN
topologies, such as mesh topology. IPv6 over OWC supports mesh
topologies with route-over.
* When an OWC 6LN is directly connected to a 6LBR, the 6LN MUST
register its address with the 6LBR by sending Neighbor
Solicitation (NS) with the Extended Address Registration Option
(EARO) [RFC8505]. When the 6LN and 6LBR are linked to each other,
6LBR assigns an address to the 6LN. In this process, Duplicate
Address Detection (DAD) [RFC6775]. is not required.
* When two or more multi-hop topology by OWC 6LNs are connected to
the 6LBR, the 6LBR performs DAD for the acquired link-local
address of the 6LNs. In this topology, 6LNs that have two or more
links with neighbor nodes may act as routers.
* For receiving RSs and RAs, the OWC 6LNs MUST follow Sections 5.3
and 5.4 of [RFC6775].
* When an OWC device is a 6LR or 6LBR, the OWC device MUST follow
Sections 6 and 7 of [RFC6775].
4.5. Header Compression
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4.5.1. Traditional 6LoWPAN 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 OWC. All headers MUST be compressed according to the encoding
formats described in [RFC6282].
Therefore, IPv6 header compression in [RFC6282] MUST be implemented.
Further, implementations MUST also support Generic Header Compression
(GHC) as described in [RFC7400].
If a 16-bit address is required as a short address, it MUST be formed
by the 16-bit OWC Link Layer Address as shown in Figure 4.
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 16-bit OWC Link Layer Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: OWC Short Address Format
4.5.2. SCHC header compression
In addition, Static Context Header Compression and fragmentation
(SCHC)[RFC8724] is optionally used in OWC networks to reduce
overhead. A signaling mechanism SHOULD be implemented to indicate
whether a node supports SCHC compression. For instance, SCHC MAY be
used to compress IPv6 headers, IPv6/UDP headers, IPv6/UDP/CoAP (if
CoAP is used), etc. [RFC8724].
In the star topology, in order to signal that a node supports SCHC
for header compression, the node uses the 6LoWPAN Capability
Indication Option (6CIO), with a new 6LoWPAN Capability Bit called
the "S" bit. This 'S' bit is intended to indicate generic SCHC
functionality, making it applicable beyond OWC networks. Future
standardization efforts may define a generic specification for the
'S' bit that extends to other link-layer technologies. The "S" bit
is the last bit (47th bit) of the "6LoWPAN Capability Bits" registry
(see Figure 5).
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length = 1 | Reserved |X|A|D|L|B|P|E|G|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |S|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: New 6LoWPAN Capability Bit in the 6CIO
New option fields:
S: 1-bit flag. Set to indicate that the node sending the 6CIO
option supports SCHC for header compression.
Typically, the 6CIO (with the "S" bit set) will only be sent in
6LoWPAN-ND Router Solicitation (RS) packets. The resulting 6LoWPAN-
ND Router Advertisement (RA) can then already make use of SCHC and
thus indicate SCHC capability implicitly.
In a multihop topology, SCHC header compression can only be used as
long as the whole 6LoWPAN network is administratively required to
support SCHC-compressed packet transmission over a multihop network.
In that case, all network nodes MUST support at least one of the
route-over modes defined in [I-D.ietf-6lo-schc-15dot4], i.e.,
Straightforward Route-Over (SRO), Tunneled, RPL-based Route-Over
(TRO) or Pointer-based Route-Over (PRO), and all network nodes MUST
use the same route-over mode at a given time.
In order to transmit a SCHC-compressed IPv6 packet over OWC, the
frame format to be used depends on the network topology (i.e., star
vs multihop) and, for multihop topologies, on the route-over mode
used. The frame format SHALL be the corresponding one defined in
Sections 4.1 to 4.3 of [I-D.ietf-6lo-schc-15dot4], where "IEEE
802.15.4 frame payload" needs to be replaced by "IEEE 802.15.7 frame
payload" in the case of IPv6 over OWC.
4.6. Fragmentation and Reassembly Considerations
For PHY1 of OWC, IPv6 over OWC MUST use [RFC4944] Fragmentation and
Reassembly (FAR). The MTU of OWC PHY1 is smaller than the MTU of
IPv6 Packet (1280 bytes). However, because the MTU of OWC PHY2 and
PHY3 are bigger than MTU of IPv6 Packet, IPv6 over OWC MUST NOT use
[RFC4944] FAR at the adaptation layer for the payloads as discussed
in Section 3.4.
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Even though OWC devices have larger MTUs (i.e., PHY2 and PHY3) than
1280 octets, use of a 1280-octet MTU is RECOMMENDED in order to avoid
need for Path MTU discovery procedures [RFC7668].
4.7. Unicast and Multicast Address Mapping
The address resolution procedure for mapping IPv6 non-multicast
addresses into OWC Link-Layer Addresses follows the general
description in Sections 4.6.1 and 7.2 of [RFC4861], unless otherwise
specified.
The Source/Target Link-Layer Address option has the following form
when the addresses are 16-bit OWC Link Layer 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) -+
| |
++-+-+-+-+-+-+-+-+-++-+-+-+-+-+-+
| OWC 16-bit Link Layer Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: Unicast Address Mapping
Option fields:
Type:
1: This is for the Source Link-Layer Address.
2: This is for the Target Link-Layer Address.
Length:
This is the length of this option (including the Type and
Length fields) in units of 8 bits. The value of this field is
1 for 16-bit OWC Link Layer addresse.
The OWC Link Layer does not support multicast. Therefore, packets
are always transmitted unicast between two OWC devices. Even in the
case where a 6LBR is attached to multiple 6LNs, the 6LBR cannot
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; the
central node, which is battery-powered, must take particular care of
power consumption. To further conserve power, the 6LBR MUST keep
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track of multicast listeners at OWC 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 OWC packet to the 6LBR.
5. Internet Connectivity Scenarios
The scenarios in this section provide useful context for
understanding OWC device network configurations. To further clarify,
OWC can operate in two primary configurations.
* Single-hop networks: Suitable for small-scale IoT applications
such as small-scale smart home automation, where OWC-enabled
devices communicate directly.
* Multi-hop networks: Suitable Where OWC devices relay data across
multiple hops to extend the network range (e.g., for industrial
IoT deployments). Additionally, interoperability with other 6lo
wireless technologies can be considered. In hybrid networks, IPv6
over OWC can coexist with these technologies by utilizing IPv6
routing mechanisms, allowing seamless integration with existing
infrastructure.
5.1. OWC Device Network Connected to the Internet
Figure 7 illustrates an example of an OWC device network connected to
the Internet. Another OWC devices may run as 6LNs and 6LRs, and they
communicate with the 6LBR, as long as both are within each other's
range.
6LN
|
OWC link → |
↓ |
6LR ------- 6LBR -- (( Internet )) -- Corresponding Node
. .
.<-Subnet--> .
. to the .
. Internet .
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Figure 7: Example of OWC Device Network Connected to the Internet
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
duplicates, since 6LNs need to register their addresses with the
6LBR.
5.2. OWC Device Multi-hop Network
In some scenarios, the OWC device network may operate as a simple,
isolated ad-hoc network, as illustrated in Figure 8. Two groups of
6LNs are interconnected in a star topology, with each group connected
to a 6LR.
6LN 6LN
| |
OWC link → | OWC link → |
↓ | ↓ |
6LN -------- 6LR -------------- 6LR ------- 6LN
. | ↑ .
. | ← OWC link .
. | .
. 6LN .
. .
. < - - - - - - - Subnet - - - - - - - - > .
Figure 8: Example of isolated OWC Device Multi-hop Network
In multihop (i.e., more complex) topologies, DAD requires the
extensions for multihop networks, such as the ones in [RFC6775].
6. IANA Considerations
IANA is requested to make the following addition to the "6LoWPAN
Capability Bits" registry, as follows:
+----------------+---------------------------+------------+
| Bit | Description | Reference |
+----------------+---------------------------+------------+
| 47 (suggested) | SCHC Support (S bit) | RFC This |
+----------------+---------------------------+------------+
Figure 9: New 6LoWPAN Capability Bit (S bit)
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7. Security Considerations
[TBD]
8. References
8.1. Normative References
[I-D.ietf-6lo-schc-15dot4]
Gomez, C. and A. Minaburo, "Transmission of SCHC-
compressed packets over IEEE 802.15.4 networks", Work in
Progress, Internet-Draft, draft-ietf-6lo-schc-15dot4-07, 2
October 2024, <https://datatracker.ietf.org/doc/html/
draft-ietf-6lo-schc-15dot4-07>.
[IEEE802.15.7]
IEEE, "IEEE Standard for Local and metropolitan area
networks--Part 15.7: Short-Range Optical Wireless
Communications", IEEE Std 802.15.7-2018,
DOI 10.1109/IEEESTD.2019.8697198, April 2019,
<https://ieeexplore.ieee.org/document/8697198>.
[RFC2462] Thomson, S. and T. Narten, "IPv6 Stateless Address
Autoconfiguration", RFC 2462, DOI 10.17487/RFC2462,
December 1998, <https://www.rfc-editor.org/info/rfc2462>.
[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>.
[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>.
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[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>.
[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>.
[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>.
[RFC8724] Minaburo, A., Toutain, L., Gomez, C., Barthel, D., and JC.
Zuniga, "SCHC: Generic Framework for Static Context Header
Compression and Fragmentation", RFC 8724,
DOI 10.17487/RFC8724, April 2020,
<https://www.rfc-editor.org/info/rfc8724>.
8.2. Informative References
[IEEE802.11bb-2023]
IEEE, "IEEE Standard for Information Technology--
Telecommunications and Information Exchange between
Systems Local and Metropolitan Area Networks--Specific
Requirements Part 11: Wireless LAN Medium Access Control
(MAC) and Physical Layer (PHY) Specifications Amendment 6:
Light Communications", IEEE Std 802.11bb-2023, June 2023,
<https://standards.ieee.org/ieee/802.11bb/10823>.
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[IEEE802.15.13-2023]
IEEE, "IEEE Standard for Multi-Gigabit per Second Optical
Wireless Communications (OWC), with Ranges up to 200 m,
for Both Stationary and Mobile Devices", IEEE
Std 802.15.13-2023, February 2023,
<https://standards.ieee.org/ieee/802.15.13/10269>.
[IEEE802.15.7a]
IEEE, "IEEE Standard for Local and Metropolitan Area
Networks - Part 15.7: Short-Range Optical Wireless
Communications Amendment 1: Higher Rate, Longer Range
Optical Camera Communication (OCC)", IEEE Std 802.15.7a-
2024, December 2024,
<https://standards.ieee.org/ieee/802.15.7a/10367>.
[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>.
[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>.
[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>.
Acknowledgements
We are grateful to the members of the IETF 6lo Working Group. Carles
Gomez has been funded in part by the Spanish Government through
project PID2019-106808RA-I00 and PID2023-146378NB-I00, and by
Secretaria d'Universitats i Recerca del Departament d'Empresa i
Coneixement de la Generalitat de Catalunya 2017 through grant SGR 376
and 2021 throught grant SGR 00330.
Authors' Addresses
Choi, et al. Expires 2 September 2025 [Page 17]
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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
Cheol-min Kim
Korea Electronics Technology Institute
25, Saenari-ro, Bundang-Gu, Seongnam-Si
Gyeonggi-do
13509
South Korea
Phone: +82 31 789 7595
Email: cmkim@keti.re.kr
Carles Gomez
Universitat Politecnica de Catalunya
C/Esteve Terradas, 7
08860 Castelldefels
Spain
Email: carlesgo@entel.upc.edu
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