draft-ietf-mboned-ieee802-mcast-problems-02.txt   draft-ietf-mboned-ieee802-mcast-problems-03.txt 
Internet Area C. Perkins Internet Area C. Perkins
Internet-Draft M. McBride Internet-Draft M. McBride
Intended status: Informational Futurewei Intended status: Informational Futurewei
Expires: February 18, 2019 D. Stanley Expires: April 26, 2019 D. Stanley
HPE HPE
W. Kumari W. Kumari
Google Google
JC. Zuniga JC. Zuniga
SIGFOX SIGFOX
August 17, 2018 October 23, 2018
Multicast Considerations over IEEE 802 Wireless Media Multicast Considerations over IEEE 802 Wireless Media
draft-ietf-mboned-ieee802-mcast-problems-02 draft-ietf-mboned-ieee802-mcast-problems-03
Abstract Abstract
Well-known issues with multicast have prevented the deployment of Well-known issues with multicast have prevented the deployment of
multicast in 802.11 [dot11], [mc-props], [mc-prob-stmt], and other multicast in 802.11 [dot11], [mc-props], [mc-prob-stmt], and other
local-area wireless environments. IETF multicast experts have been local-area wireless environments. IETF multicast experts have been
meeting together to discuss these issues and provide IEEE updates. meeting together to discuss these issues and provide IEEE updates.
The mboned working group is chartered to receive regular reports on The mboned working group is chartered to receive regular reports on
the current state of the deployment of multicast technology, create the current state of the deployment of multicast technology, create
"practice and experience" documents that capture the experience of "practice and experience" documents that capture the experience of
skipping to change at page 2, line 4 skipping to change at page 2, line 4
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 18, 2019. This Internet-Draft will expire on April 26, 2019.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
skipping to change at page 2, line 39 skipping to change at page 2, line 39
3.1.3. High Interference . . . . . . . . . . . . . . . . . . 6 3.1.3. High Interference . . . . . . . . . . . . . . . . . . 6
3.1.4. Power-save Effects on Multicast . . . . . . . . . . . 6 3.1.4. Power-save Effects on Multicast . . . . . . . . . . . 6
3.2. Issues at Layer 3 and Above . . . . . . . . . . . . . . . 7 3.2. Issues at Layer 3 and Above . . . . . . . . . . . . . . . 7
3.2.1. IPv4 issues . . . . . . . . . . . . . . . . . . . . . 7 3.2.1. IPv4 issues . . . . . . . . . . . . . . . . . . . . . 7
3.2.2. IPv6 issues . . . . . . . . . . . . . . . . . . . . . 8 3.2.2. IPv6 issues . . . . . . . . . . . . . . . . . . . . . 8
3.2.3. MLD issues . . . . . . . . . . . . . . . . . . . . . 8 3.2.3. MLD issues . . . . . . . . . . . . . . . . . . . . . 8
3.2.4. Spurious Neighbor Discovery . . . . . . . . . . . . . 9 3.2.4. Spurious Neighbor Discovery . . . . . . . . . . . . . 9
4. Multicast protocol optimizations . . . . . . . . . . . . . . 9 4. Multicast protocol optimizations . . . . . . . . . . . . . . 9
4.1. Proxy ARP in 802.11-2012 . . . . . . . . . . . . . . . . 10 4.1. Proxy ARP in 802.11-2012 . . . . . . . . . . . . . . . . 10
4.2. IPv6 Address Registration and Proxy Neighbor Discovery . 10 4.2. IPv6 Address Registration and Proxy Neighbor Discovery . 10
4.3. Buffering to Improve Battery Life . . . . . . . . . . . . 11 4.3. Buffering to Improve Battery Life . . . . . . . . . . . . 12
4.4. IPv6 support in 802.11-2012 . . . . . . . . . . . . . . . 12 4.4. IPv6 support in 802.11-2012 . . . . . . . . . . . . . . . 12
4.5. Conversion of multicast to unicast . . . . . . . . . . . 12 4.5. Conversion of multicast to unicast . . . . . . . . . . . 13
4.6. Directed Multicast Service (DMS) . . . . . . . . . . . . 13 4.6. Directed Multicast Service (DMS) . . . . . . . . . . . . 13
4.7. GroupCast with Retries (GCR) . . . . . . . . . . . . . . 13 4.7. GroupCast with Retries (GCR) . . . . . . . . . . . . . . 13
5. Operational optimizations . . . . . . . . . . . . . . . . . . 14 5. Operational optimizations . . . . . . . . . . . . . . . . . . 14
5.1. Mitigating Problems from Spurious Neighbor Discovery . . 14 5.1. Mitigating Problems from Spurious Neighbor Discovery . . 14
6. Multicast Considerations for Other Wireless Media . . . . . . 16 6. Multicast Considerations for Other Wireless Media . . . . . . 16
7. Recommendations . . . . . . . . . . . . . . . . . . . . . . . 16 7. Recommendations . . . . . . . . . . . . . . . . . . . . . . . 16
8. Discussion Items . . . . . . . . . . . . . . . . . . . . . . 16 8. Discussion Items . . . . . . . . . . . . . . . . . . . . . . 17
9. Security Considerations . . . . . . . . . . . . . . . . . . . 17 9. Security Considerations . . . . . . . . . . . . . . . . . . . 17
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 17 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 17
12. Informative References . . . . . . . . . . . . . . . . . . . 17 12. Informative References . . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 20
1. Introduction 1. Introduction
Performance issues have been observed when multicast packet Performance issues have been observed when multicast packet
transmissions of IETF protocols are used over IEEE 802 wireless transmissions of IETF protocols are used over IEEE 802 wireless
media. Even though enhamcements for multicast transmissions have media. Even though enhamcements for multicast transmissions have
been designed at both IETF and IEEE 802, incompatibilities still been designed at both IETF and IEEE 802, incompatibilities still
exist between specifications, implementations and configuration exist between specifications, implementations and configuration
choices. choices.
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o Packets can also be discarded due to buffer limitations in the AP o Packets can also be discarded due to buffer limitations in the AP
and non-AP STA. and non-AP STA.
3.2. Issues at Layer 3 and Above 3.2. Issues at Layer 3 and Above
This section identifies some representative IETF protocols, and This section identifies some representative IETF protocols, and
describes possible negative effects due to performance degradation describes possible negative effects due to performance degradation
when using multicast transmissions for control messages. Common uses when using multicast transmissions for control messages. Common uses
of multicast include: of multicast include:
o Control plane for IPv4 and IPv6 o Control plane signaling
o ARP and Neighbor Discovery o Neighbor Discovery
o Address Resolution
o Service discovery o Service discovery
o Applications (video delivery, stock data etc) o Applications (video delivery, stock data, etc.)
o On-demand routing
o Backbone construction
o Other L3 protocols (non-IP) o Other L3 protocols (non-IP)
User Datagram Protocol (UDP) is the most common transport layer
protocol for multicast applications. By itself, UDP is not reliable
-- messages may be lost or delivered out of order.
3.2.1. IPv4 issues 3.2.1. IPv4 issues
The following list contains a few representative IPv4 protocols using The following list contains a few representative IPv4 protocols using
multicast. multicast.
o ARP o ARP
o DHCP o DHCP
o mDNS o mDNS
After initial configuration, ARP and DHCP occur much less commonly. After initial configuration, ARP and DHCP occur much less commonly,
But service discovery can occur at any time. Apple's Bonjour but service discovery can occur at any time. Apple's Bonjour
protocol, for instance, provides service discovery (for printing) protocol, for instance, provides service discovery (for printing)
that utilizes multicast. It's the first thing operators drop. Even that utilizes multicast. It's often the first service that operators
if multicast snooping is utilized, many devices register at once drop. Even if multicast snooping is utilized, many devices can
using Bonjour, causing serious network degradation. register at once using Bonjour, causing serious network degradation.
3.2.2. IPv6 issues 3.2.2. IPv6 issues
IPv6 makes much more extensive use of multicast, including the IPv6 makes extensive use of multicast, including the following:
following:
o DHCPv6 o DHCPv6
o IPv6 Neighbor Discovery Protocol (NDP) is not very tolerant of o IPv6 Neighbor Discovery Protocol (NDP)
packet losses. In particular, the Duplicate Address Detection o Duplicate Address Detection (DAD)
(DAD) process fails when the owner of an address does not receive o Address Resolution
the multicast DAD message from another node that wishes to own o Service Discovery
that same address. This can result in an address being duplicated o Route Discovery
in the subnet, breaking a basic assumption of IPv6 connectivity. o Decentralized Address Assignment
o IPv6 NDP Neighbor Solicitation (NS) messages used in DAD and o Geographic routing
Address Lookup make use of Link-Scope multicast. In contrast to
IPv4, an IPv6 Node will typically use multiple addresses, and may
change them often for privacy reasons. This multiplies the impact
of multicast messages that are associated to the mobility of a
Node. Router advertisement (RA) messages are also periodically
multicasted over the Link.
o Neighbors may be considered lost if several consecutive packets
fail.
Address Resolution
Service Discovery
Route Discovery IPv6 NDP Neighbor Solicitation (NS) messages used in DAD and Address
Lookup make use of Link-Scope multicast. In contrast to IPv4, an
IPv6 Node will typically use multiple addresses, and may change them
often for privacy reasons. This multiplies the impact of multicast
messages that are associated to the mobility of a Node. Router
advertisement (RA) messages are also periodically multicasted over
the Link.
Decentralized Address Assignment IPv6 NDP Neighbor Solicitation (NS) messages used in DAD and Address
Lookup make use of Link-Scope multicast. In contrast to IPv4, an
IPv6 Node will typically use multiple addresses, and may change them
often for privacy reasons. This multiplies the impact of multicast
messages that are associated to the mobility of a Node. Router
advertisement (RA) messages are also periodically multicasted over
the Link.
Geographic routing Neighbors may be considered lost if several consecutive Neighbor
Discovery packets fail.
3.2.3. MLD issues 3.2.3. MLD issues
Multicast Listener Discovery(MLD) [RFC4541] is often used to identify Multicast Listener Discovery(MLD) [RFC4541] is often used to identify
members of a multicast group that are connected to the ports of a members of a multicast group that are connected to the ports of a
switch. Forwarding multicast frames into a WiFi-enabled area can use switch. Forwarding multicast frames into a WiFi-enabled area can use
such switch support for hardware forwarding state information. such switch support for hardware forwarding state information.
However, since IPv6 makes heavy use of multicast, each STA with an However, since IPv6 makes heavy use of multicast, each STA with an
IPv6 address will require state on the switch for several and IPv6 address will require state on the switch for several and
possibly many multicast solicited-node addresses. Multicast possibly many multicast solicited-node addresses. Multicast
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(6LoWPAN) denotes a low power lossy network (LLN) that supports (6LoWPAN) denotes a low power lossy network (LLN) that supports
6LoWPAN Header Compression (HC) [RFC6282]. A 6TiSCH network 6LoWPAN Header Compression (HC) [RFC6282]. A 6TiSCH network
[I-D.ietf-6tisch-architecture] is an example of a 6LowPAN. In order [I-D.ietf-6tisch-architecture] is an example of a 6LowPAN. In order
to control the use of IPv6 multicast over 6LoWPANs, the 6LoWPAN to control the use of IPv6 multicast over 6LoWPANs, the 6LoWPAN
Neighbor Discovery (6LoWPAN ND) [RFC6775] standard defines an address Neighbor Discovery (6LoWPAN ND) [RFC6775] standard defines an address
registration mechanism that relies on a central registry to assess registration mechanism that relies on a central registry to assess
address uniqueness, as a substitute to the inefficient Duplicate address uniqueness, as a substitute to the inefficient Duplicate
Address Detection (DAD) mechanism found in the mainstream IPv6 Address Detection (DAD) mechanism found in the mainstream IPv6
Neighbor Discovery Protocol (NDP) [RFC4861][RFC4862]. Neighbor Discovery Protocol (NDP) [RFC4861][RFC4862].
The 6lo Working Group is now completing an update The 6lo Working Group has specified an update
[I-D.ietf-6lo-rfc6775-update] to RFC6775. The update enables the [I-D.ietf-6lo-rfc6775-update] to RFC6775. Wireless devices can
registration to a Backbone Router [I-D.ietf-6lo-backbone-router], register their address to a Backbone Router
which proxies for the registered addresses with the mainstream IPv6 [I-D.ietf-6lo-backbone-router], which proxies for the registered
NDP running on a high speed aggragating backbone. The update also addresses with the IPv6 NDP running on a high speed aggregating
enables a proxy registration on behalf of the registered node, e.g. backbone. The update also enables a proxy registration mechanism on
by a 6LoWPAN router to which the mobile node is attached. behalf of the registered node, e.g. by a 6LoWPAN router to which the
mobile node is attached.
The general idea behind the backbone router concept is that in a The general idea behind the backbone router concept is that broadcast
variety of Wireless Local Area Networks (WLANs) and Wireless Personal and multicast messaging should be tightly controlled in a variety of
Area Networks (WPANs), the broadcast/multicast domain should be Wireless Local Area Networks (WLANs) and Wireless Personal Area
controlled, and connectivity to a particular link that provides the Networks (WPANs). Connectivity to a particular link that provides
subnet should be left to Layer-3. The model for the Backbone Router the subnet should be left to Layer-3. The model for the Backbone
operation is represented in Figure 1. Router operation is represented in Figure 1.
| |
+-----+ +-----+
| | Gateway (default) router | | Gateway (default) router
| | | |
+-----+ +-----+
| |
| Backbone Link | Backbone Link
+--------------------+------------------+ +--------------------+------------------+
| | | | | |
+-----+ +-----+ +-----+ +-----+ +-----+ +-----+
| | Backbone | | Backbone | | Backbone | | Backbone | | Backbone | | Backbone
| | router | | router | | router | | router 1 | | router 2 | | router 3
+-----+ +-----+ +-----+ +-----+ +-----+ +-----+
o o o o o o o o o o o o
o o o o o o o o o o o o o o o o o o o o o o o o o o o o
o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o
o o o o o o o o o o o o o o o o o o o o
o o o o o o o o o o o o o o
LLN LLN LLN LLN 1 LLN 2 LLN 3
Figure 1: Backbone Link and Backbone Routers Figure 1: Backbone Link and Backbone Routers
LLN nodes can move freely from an LLN anchored at one IPv6 Backbone LLN nodes can move freely from an LLN anchored at one IPv6 Backbone
Router to an LLN anchored at another Backbone Router on the same Router to an LLN anchored at another Backbone Router on the same
backbone, keeping any of the IPv6 addresses they have configured. backbone, keeping any of the IPv6 addresses they have configured.
The Backbone Routers maintain a Binding Table of their Registered The Backbone Routers maintain a Binding Table of their Registered
Nodes, which serves as a distributed database of all the LLN Nodes. Nodes, which serves as a distributed database of all the LLN Nodes.
An extension to the Neighbor Discovery Protocol is introduced to An extension to the Neighbor Discovery Protocol is introduced to
exchange that information across the Backbone Link in the reactive exchange Binding Table information across the Backbone Link as needed
fashion of mainstream IPv6 Neighbor Discovery. for the operation of IPv6 Neighbor Discovery.
RFC6775 and follow-on work (e.g., [I-D.ietf-6lo-ap-nd], are designed RFC6775 and follow-on work (e.g., [I-D.ietf-6lo-ap-nd], do address
to address the needs of LLNs, but the techniques are likely to be the needs of LLNs, and similar techniques are likely to be valuable
valuable on any type of link where sleeping devices are attached, or on any type of link where sleeping devices are attached, or where the
where the use of broadcast and multicast operations should be use of broadcast and multicast operations should be limited.
limited.
4.3. Buffering to Improve Battery Life 4.3. Buffering to Improve Battery Life
Methods have been developed to help save battery life; for example, a Methods have been developed to help save battery life; for example, a
device might not wake up when the AP receives a multicast packet. device might not wake up when the AP receives a multicast packet.
The AP acts on behalf of STAs in various ways. To enable use of the The AP acts on behalf of STAs in various ways. To enable use of the
power-saving feature for STAs in its BSS, the AP buffers frames for power-saving feature for STAs in its BSS, the AP buffers frames for
delivery to the STA at the time when the STA is scheduled for delivery to the STA at the time when the STA is scheduled for
reception. If an AP, for instance, expresses a DTIM (Delivery reception. If an AP, for instance, expresses a DTIM (Delivery
Traffic Indication Message) of 3 then the AP will send a multicast Traffic Indication Message) of 3 then the AP will send a multicast
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keeping the network working and stable is the first priority keeping the network working and stable is the first priority
and a stateful firewall may be required in order to achieve and a stateful firewall may be required in order to achieve
this. this.
6. Multicast Considerations for Other Wireless Media 6. Multicast Considerations for Other Wireless Media
Many of the causes of performance degradation described in earlier Many of the causes of performance degradation described in earlier
sections are also observable for wireless media other than 802.11. sections are also observable for wireless media other than 802.11.
For instance, problems with power save, excess media occupancy, and For instance, problems with power save, excess media occupancy, and
poor reliability will also affect 802.15.3 and 802.15.4. However, poor reliability will also affect 802.15.3 and 802.15.4.
802.15 media specifications do not include mechanisms similar to Unfortunately, 802.15 media specifications do not yet include
those developed for 802.11. In fact, the design philosophy for mechanisms similar to those developed for 802.11. In fact, the
802.15 is oriented towards minimality, with the result that many such design philosophy for 802.15 is oriented towards minimality, with the
functions would more likely be relegated to operation within higher result that many such functions are relegated to operation within
layer protocols. This leads to a patchwork of non-interoperable and higher layer protocols. This leads to a patchwork of non-
vendor-specific solutions. See [uli] for some additional discussion, interoperable and vendor-specific solutions. See [uli] for some
and a proposal for a task group to resolve similar issues, in which additional discussion, and a proposal for a task group to resolve
the multicast problems might be considered for mitigation. similar issues, in which the multicast problems might be considered
for mitigation.
7. Recommendations 7. Recommendations
This section will provide some recommendations about the usage and This section will provide some recommendations about the usage and
combinations of the multicast enhancements described in Section 4 and combinations of the multicast enhancements described in Section 4 and
Section 5. Section 5.
Future protocol documents utilizing multicast signaling should be
carefully scrutinized if the protocol is likely to be used over
wireless media.
Proxy methods should be encouraged to conserve network bandwidth and
power utilization by low-power devices. The device can use a unicast
message to its proxy, and then the proxy can take care of any needed
multicast operations.
Multicast signaling for wireless devices should be done in a way
compatible with low-duty cycle operation.
(FFS) (FFS)
8. Discussion Items 8. Discussion Items
This section will suggest some discussion items for further This section suggests two discussion items for further resolution.
resolution.
The IETF may need to decide that broadcast is more expensive so The IETF should determine guidelines by which it may be decided that
multicast needs to be sent wired. For example, 802.1ak works on multicast packets are to be sent wired. For example, 802.1ak works
ethernet and wifi. 802.1ak has been pulled into 802.1Q as of 802.1Q- on ethernet and wifi. 802.1ak has been pulled into 802.1Q as of
2011. 802.1Q-2014 can be looked at here: http://www.ieee802.org/1/ 802.1Q-2011. 802.1Q-2014 can be found here:
pages/802.1Q-2014.html. If a generic solution is not found, http://www.ieee802.org/1/pages/802.1Q-2014.html. If a generic
guidelines for multicast over wifi should be established. solution is not found, guidelines for multicast over wifi should be
established.
To provide an idea going forward, perhaps a reliable registration to Perhaps a reliable registration to Layer-2 multicast groups and a
Layer-2 multicast groups and a reliable multicast operation at reliable multicast operation at Layer-2 could provide a generic
Layer-2 could provide a generic solution. There is no need to solution. There is no need to support 2^24 groups to get solicited
support 2^24 groups to get solicited node multicast working: it is node multicast working: it is possible to simply select a number of
possible to simply select a number of trailing bits that make sense trailing bits that make sense for a given network size to limit the
for a given network size to limit the amount of unwanted deliveries amount of unwanted deliveries to reasonable levels. IEEE 802.1,
to reasonable levels. IEEE 802.1, 802.11, and 802.15 should be 802.11, and 802.15 should be encouraged to revisit L2 multicast
encouraged to revisit L2 multicast issues. In particular, Wi-Fi issues. In reality, Wi-Fi provides a broadcast service, not a
provides a broadcast service, not a multicast one; at the PHY level, multicast service. On the physical medium, all frames are broadcast
all frames are broadcast except in very unusual cases in which except in very unusual cases in which special beamforming
special beamforming transmitters are used. Unicast offers the transmitters are used. Unicast offers the advantage of being much
advantage of being much faster (2 orders of magnitude) and much more faster (2 orders of magnitude) and much more reliable (L2 ARQ).
reliable (L2 ARQ).
9. Security Considerations 9. Security Considerations
This document does not introduce any security mechanisms, and does This document does not introduce any security mechanisms, and does
not have affect existing security mechanisms. not have affect existing security mechanisms.
10. IANA Considerations 10. IANA Considerations
This document does not specify any IANA actions. This document does not request any IANA actions.
11. Acknowledgements 11. Acknowledgements
This document has benefitted from discussions with the following This document has benefitted from discussions with the following
people, in alphabetical order: Pascal Thubert people, in alphabetical order: Pascal Thubert
12. Informative References 12. Informative References
[arpsponge] [arpsponge]
Arien Vijn, Steven Bakker, "Arp Sponge", March 2015. Arien Vijn, Steven Bakker, "Arp Sponge", March 2015.
skipping to change at page 18, line 11 skipping to change at page 18, line 29
[dot11-proxyarp] [dot11-proxyarp]
P802.11, "Proxy ARP in 802.11ax", September 2015. P802.11, "Proxy ARP in 802.11ax", September 2015.
[dot11aa] P802.11, "Part 11: Wireless LAN Medium Access Control [dot11aa] P802.11, "Part 11: Wireless LAN Medium Access Control
(MAC) and Physical Layer (PHY) Specifications Amendment 2: (MAC) and Physical Layer (PHY) Specifications Amendment 2:
MAC Enhancements for Robust Audio Video Streaming", March MAC Enhancements for Robust Audio Video Streaming", March
2012. 2012.
[I-D.ietf-6lo-ap-nd] [I-D.ietf-6lo-ap-nd]
Thubert, P., Sarikaya, B., and M. Sethi, "Address Thubert, P., Sarikaya, B., Sethi, M., and R. Struik,
Protected Neighbor Discovery for Low-power and Lossy "Address Protected Neighbor Discovery for Low-power and
Networks", draft-ietf-6lo-ap-nd-06 (work in progress), Lossy Networks", draft-ietf-6lo-ap-nd-08 (work in
February 2018. progress), October 2018.
[I-D.ietf-6lo-backbone-router] [I-D.ietf-6lo-backbone-router]
Thubert, P., "IPv6 Backbone Router", draft-ietf-6lo- Thubert, P. and C. Perkins, "IPv6 Backbone Router", draft-
backbone-router-06 (work in progress), February 2018. ietf-6lo-backbone-router-08 (work in progress), October
2018.
[I-D.ietf-6lo-rfc6775-update] [I-D.ietf-6lo-rfc6775-update]
Thubert, P., Nordmark, E., Chakrabarti, S., and C. Thubert, P., Nordmark, E., Chakrabarti, S., and C.
Perkins, "Registration Extensions for 6LoWPAN Neighbor Perkins, "Registration Extensions for 6LoWPAN Neighbor
Discovery", draft-ietf-6lo-rfc6775-update-21 (work in Discovery", draft-ietf-6lo-rfc6775-update-21 (work in
progress), June 2018. progress), June 2018.
[I-D.ietf-6tisch-architecture] [I-D.ietf-6tisch-architecture]
Thubert, P., "An Architecture for IPv6 over the TSCH mode Thubert, P., "An Architecture for IPv6 over the TSCH mode
of IEEE 802.15.4", draft-ietf-6tisch-architecture-14 (work of IEEE 802.15.4", draft-ietf-6tisch-architecture-15 (work
in progress), April 2018. in progress), October 2018.
[ietf_802-11] [ietf_802-11]
Dorothy Stanley, "IEEE 802.11 multicast capabilities", Nov Dorothy Stanley, "IEEE 802.11 multicast capabilities", Nov
2015. 2015.
[mc-ack-mux] [mc-ack-mux]
Yusuke Tanaka et al., "Multiplexing of Acknowledgements Yusuke Tanaka et al., "Multiplexing of Acknowledgements
for Multicast Transmission", July 2015. for Multicast Transmission", July 2015.
[mc-prob-stmt] [mc-prob-stmt]
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