Re: [ipwave] Review comments on draft-ietf-ipwave-ipv6-over-80211ocb-04.txt

Alexandre Petrescu <alexandre.petrescu@gmail.com> Wed, 30 August 2017 14:33 UTC

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To: Sri Gundavelli <sgundave@cisco.com>
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Cc: its@ietf.org
From: Alexandre Petrescu <alexandre.petrescu@gmail.com>
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Date: Wed, 30 Aug 2017 16:33:10 +0200
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Archived-At: <https://mailarchive.ietf.org/arch/msg/its/lgQAM6sCT9O2BE49Me1nI_LT7GU>
Subject: Re: [ipwave] Review comments on draft-ietf-ipwave-ipv6-over-80211ocb-04.txt
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Sri,

I want to let you know I have today finished to read the entire set of
comments.  I will try to address them soon.

Alex

Le 28/08/2017 à 05:00, Sri Gundavelli (sgundave) a écrit :
> 
> Attached is my review feedback.
> 
> In general there is lot of good information in the document. But,
> there are also few areas where additional clarifications will greatly
> help.
> 
> 1.) Its not clear, if the document makes any assumption on the
> operating environment/communication profile. There is not much
> discussion on that aspect; For example, Is it always a one-hop
> communication between RSU and OBU where the 802.11-OCB link?  So, is
> the use of IPv6 only in that context of 1-hop communication?
> 
> 2.) There is also no discussion on how these links get formed in 
> vehicular environment and when they are attached/detached.
> 
> 3.) How do nodes discover each other?  How does ND resolution work?
> Are these messages received by a multiple RSU’s, or a single RSU?
> Whats the implication of that. Note that you don’t have that issue in
> 802.11, given the association to an access point, which in turn maps
> the links to a VLAN/subnet.
> 
> 4.) What happens as a vehicle moves between RSU’s, how does it impact
>  address configuration?   Is DHCPv6 based address configuration
> relevant here?
> 
> 
> Please see inline for additional comments.
> 
[...]
> 
> Transmission of IPv6 Packets over IEEE 802.11 Networks in mode
> Outside
> 
> 
> 
> 
> 
> the Context of a Basic Service Set (IPv6-over-80211ocb)
> 
> 
> 
> 
> 
> draft-ietf-ipwave-ipv6-over-80211ocb-04.txt
> 
> 
> 
> 
> [Sri] May be change to, “..in mode .." —> “..operating in mode ..”?
> 
> 
> 
> Abstract
> 
> In order to transmit IPv6 packets on IEEE 802.11 networks run
> outside the context of a basic service set (OCB, earlier "802.11p")
> there is a need to define a few parameters such as the recommended
> Maximum Transmission Unit size, the header format preceding the IPv6
> header, the Type value within it, and others.  This document
> describes these parameters for IPv6 and IEEE 802.11 OCB networks; it
> portrays the layering of IPv6 on 802.11 OCB similarly to other known
> 802.11 and Ethernet layers - by using an Ethernet Adaptation Layer.
> 
> [Sri] Is it “recommended MTU size", or "supported MTU size on the
> 802.11 OCB link?
> 
> 
> 
> In addition, the document attempts to list what is different in 
> 802.11 OCB (802.11p) compared to more 'traditional' 802.11a/b/g/n 
> layers, layers over which IPv6 protocols operates without issues. 
> Most notably, the operation outside the context of a BSS (OCB) has 
> impact on IPv6 handover behaviour and on IPv6 security.
> 
> [Sri] Minor comment. May be instead of using the “layer” terminology,
>  you may want to present this as IPv6 support on "802.11 OCB" links.
> 
> 
> An example of an IPv6 packet captured while transmitted over an IEEE 
> 802.11 OCB link (802.11p) is given.
> 
> [Sri] Last paragraph can be ommitted in my view. That’s too much of 
> detail for Abstract.
> 
> 
> Status of This Memo
> 
> This Internet-Draft is submitted in full conformance with the 
> provisions ofBCP 78 <https://tools.ietf.org/html/bcp78>  andBCP 79
> <https://tools.ietf.org/html/bcp79>.
> 
> Internet-Drafts are working documents of the Internet Engineering 
> Task Force (IETF).  Note that other groups may also distribute
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 1]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-2>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> working documents as Internet-Drafts.  The list of current Internet- 
> Drafts is athttp://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 February 18, 2018.
> 
> Copyright Notice
> 
> Copyright (c) 2017 IETF Trust and the persons identified as the 
> document authors.  All rights reserved.
> 
> This document is subject toBCP 78 <https://tools.ietf.org/html/bcp78>
> and the IETF Trust's Legal Provisions Relating to IETF Documents 
> (http://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 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-1>.
> Introduction  . . . . . . . . . . . . . . . . . . . . . . . .3 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-3>
>
> 
2
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-2>.
> Terminology . . . . . . . . . . . . . . . . . . . . . . . . .5 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-5>
>
> 
3.  Communication Scenarios where IEEE 802.11 OCB Links are Used    6
> 4 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-4>.
> Aspects introduced by the OCB mode to 802.11  . . . . . . . .6 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-6>
>
> 
5
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5>.
> Layering of IPv6 over 802.11-OCB as over Ethernet . . . . . .10 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-10>
>
> 
5.1
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.1>.
> Maximum Transmission Unit (MTU) . . . . . . . . . . . . .10 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-10>
>
> 
5.2
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.2>.
> Frame Format  . . . . . . . . . . . . . . . . . . . . . .11 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-11>
>
> 
5.2.1
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.2.1>.
> Ethernet Adaptation Layer . . . . . . . . . . . . . .12 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-12>
>
> 
5.3
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.3>.
> Link-Local Addresses  . . . . . . . . . . . . . . . . . .13 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-13>
>
> 
5.4
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.4>.
> Address Mapping . . . . . . . . . . . . . . . . . . . . .14 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-14>
>
> 
5.4.1
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.4.1>.
> Address Mapping -- Unicast  . . . . . . . . . . . . .14 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-14>
>
> 
5.4.2
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.4.2>.
> Address Mapping -- Multicast  . . . . . . . . . . . .14 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-14>
>
> 
5.5
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.5>.
> Stateless Autoconfiguration . . . . . . . . . . . . . . .15 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-15>
>
> 
5.6
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.6>.
> Subnet Structure  . . . . . . . . . . . . . . . . . . . .16 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-16>
>
> 
6
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-6>.
> Example IPv6 Packet captured over a IEEE 802.11-OCB link  . .16 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-16>
>
> 
6.1
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-6.1>.
> Capture in Monitor Mode . . . . . . . . . . . . . . . . .17 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-17>
>
> 
6.2
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-6.2>.
> Capture in Normal Mode  . . . . . . . . . . . . . . . . .19 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-19>
>
> 
7
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-7>.
> Security Considerations . . . . . . . . . . . . . . . . . . .21 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-21>
>
> 
8
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-8>.
> IANA Considerations . . . . . . . . . . . . . . . . . . . . .22 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-22>
>
> 
9
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-9>.
> Contributors  . . . . . . . . . . . . . . . . . . . . . . . .22 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-22>
>
> 
10
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-10>.
> Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .22 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-22>
>
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 2]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-3>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> 11 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-11>.
> References  . . . . . . . . . . . . . . . . . . . . . . . . .23 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-23>
>
> 
11.1
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-11.1>.
> Normative References . . . . . . . . . . . . . . . . . .23 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-23>
>
> 
11.2
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-11.2>.
> Informative References . . . . . . . . . . . . . . . . .24 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-24>
>
> 
Appendix A
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-A>.
> ChangeLog  . . . . . . . . . . . . . . . . . . . . .26 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-26>
>
> 
Appendix B
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-B>.
> Changes Needed on a software driver 802.11a to become a
> 802.11-OCB driver . . .28 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-28>
>
> 
Appendix C
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C>.
> Design Considerations  . . . . . . . . . . . . . . .30 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-30>
>
> 
C.1
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C.1>.
> Vehicle ID  . . . . . . . . . . . . . . . . . . . . . . .30 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-30>
>
> 
C.2
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C.2>.
> Reliability Requirements  . . . . . . . . . . . . . . . .30 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-30>
>
> 
C.3
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C.3>.
> Multiple interfaces . . . . . . . . . . . . . . . . . . .31 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-31>
>
> 
C.4
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C.4>.
> MAC Address Generation  . . . . . . . . . . . . . . . . .32 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-32>
>
> 
Appendix D
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-D>.
> IEEE 802.11 Messages Transmitted in OCB mode . . . .32 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-32>
>
> 
Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .32
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-32>
>
> 
> 
> 1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-1>.
>
> 
Introduction
> 
> 
> 
> This document describes the transmission of IPv6 packets on IEEE Std 
> 802.11 OCB networks (earlier known as 802.11p).
> 
> 
> [Sri] Please add a reference to the IEEE specification that defines
> the OCB mode.
> 
> 
> 
> This involves the layering of IPv6 networking on top of the IEEE
> 802.11 MAC layer (with an LLC layer).  Compared to running IPv6 over
> the Ethernet MAC layer, there is no modification required to the
> standards: IPv6 works fine directly over 802.11 OCB too (with an LLC
> layer).
> 
> The term "802.11p" is an earlier definition.  As of year 2012, the 
> behaviour of "802.11p" networks has been rolled in the document IEEE 
> Std 802.11-2012.  In this document the term 802.11p disappears. 
> Instead, each 802.11p feature is conditioned by a flag in the 
> Management Information Base.  That flag is named "OCBActivated". 
> Whenever OCBActivated is set to true the feature it relates to 
> represents an earlier 802.11p feature.  For example, an 802.11 
> STAtion operating outside the context of a basic service set has the 
> OCBActivated flag set.  Such a station, when it has the flag set, it 
> uses a BSS identifier equal to ff:ff:ff:ff:ff:ff.
> 
> In the following text we use the term "802.11p" to mean 802.11-2012 
> OCB.
> 
> The IPv6 network layer operates on 802.11 OCB in the same manner as 
> it operates on 802.11 WiFi, with a few particular exceptions.  The 
> IPv6 network layer operates on WiFi by involving an Ethernet 
> Adaptation Layer; this Ethernet Adaptation Layer maps 802.11 headers 
> to Ethernet II headers.  The operation of IP on Ethernet is
> described in [RFC1042 <https://tools.ietf.org/html/rfc1042>] and
> [RFC2464 <https://tools.ietf.org/html/rfc2464>].  The situation of
> IPv6 networking layer on Ethernet Adaptation Layer is illustrated
> below:
> 
> 
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 3]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-4>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |                 IPv6
> | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |       Ethernet
> Adaptation Layer       | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> 802.11 WiFi MAC           | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |             802.11 WiFi
> PHY           | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> 
> (in the above figure, a WiFi profile is represented; this is used 
> also for OCB profile.)
> 
> A more theoretical and detailed view of layer stacking, and 
> interfaces between the IP layer and 802.11 OCB layers, is
> illustrated below.  The IP layer operates on top of the EtherType
> Protocol Discrimination (EPD); this Discrimination layer is described
> in IEEE Std 802.3-2012; the interface between IPv6 and EPD is the
> LLC_SAP (Link Layer Control Service Accesss Point).
> 
> 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |                 IPv6
> | +-+-+-+-+-+-{            }+-+-+-+-+-+-+-+ {   LLC_SAP  }
> 802.11 OCB +-+-+-+-+-+-{            }+-+-+-+-+-+-+-+  Boundary |
> EPD          |       |     | |                         | MLME  |
> | +-+-+-{  MAC_SAP   }+-+-+-|  MLME_SAP   | |      MAC Sublayer
> |       |     |  802.11 OCB |     and ch. coord.      |       | SME |
> Services +-+-+-{   PHY_SAP  }+-+-+-+-+-+-+-|     | |
> | PLME  |     | |            PHY Layer    |   PLME_SAP  | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> 
> In addition to the description of interface between IP and MAC using 
> "Ethernet Adaptation Layer" and "Ethernet Protocol Discrimination 
> (EPD)" it is worth mentioning that SNAP [RFC1042
> <https://tools.ietf.org/html/rfc1042>] is used to carry the IPv6
> Ethertype.
> 
> However, there may be some deployment considerations helping
> optimize the performances of running IPv6 over 802.11-OCB (e.g. in
> the case of handovers between 802.11 OCB-enabled access routers, or
> the consideration of using the IP security layer [RFC4301
> <https://tools.ietf.org/html/rfc4301>]).
> 
> 
> 
> 
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> 
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>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-5>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> There are currently no specifications for handover between OCB links 
> since these are currently specified as LLC-1 links (i.e. 
> connectionless).  Any handovers must be performed above the Data
> Link Layer.  Also, while there is no encryption applied below the
> network layer using 802.11p, 1609.2 [ieee1609.2 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-ieee1609.2>]
> does provide security services for applications to use so that there
> can easily be data security over the air without invoking IPsec.
> 
> We briefly introduce the vehicular communication scenarios where
> IEEE 802.11-OCB links are used.
> 
> 
> [Sri] I have not seen much discussion on the link / communication 
> assumptions.
> 
> 
> 
> This is followed by a description of differences in specification
> terms, between 802.11 OCB and 802.11a/b/g/n (and the same differences
> expressed in terms of requirements to software implementation are
> listed inAppendix B 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-B>.)
>
>  The document then concentrates on the parameters of layering IP
> over 802.11 OCB as over Ethernet: value of MTU, the contents of
> Frame Format, the rules for forming Interface Identifiers, the
> mechanism for Address Mapping and for State-less Address
> Auto-configuration. These are precisely the same as IPv6 over
> Ethernet [RFC2464 <https://tools.ietf.org/html/rfc2464>].
> 
> As an example, these characteristics of layering IPv6 straight over 
> LLC over 802.11 OCB MAC are illustrated by dissecting an IPv6 packet 
> captured over a 802.11 OCB link; this is described in the section 
> Section 6 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-6>.
>
>  A couple of points can be considered as different, although they
> are not required in order to have a working implementation of
> IPv6-over- 802.11-OCB.  These points are consequences of the OCB
> operation which is particular to 802.11 OCB (Outside the Context of a
> BSS).  First, the handovers between OCB links need specific behaviour
> for IP Router Advertisements, or otherwise 802.11 OCB's Time
> Advertisement, or of higher layer messages such as the 'Basic Safety
> Message' (in the US) or the 'Cooperative Awareness Message' (in the
> EU) or the 'WAVE Routing Advertisement'; second, the IP security
> mechanisms are necessary, since OCB means that 802.11 is stripped of
> all 802.11 link-layer security; a small additional security aspect
> which is shared between 802.11 OCB and other 802.11 links is the
> privacy concerns related to the address formation mechanisms.
> 
> In the published literature, many documents describe aspects related 
> to running IPv6 over 802.11 OCB: 
> [I-D.jeong-ipwave-vehicular-networking-survey 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-I-D.jeong-ipwave-vehicular-networking-survey>].
>
> 
> 
> 2 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-2>.
>
> 
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 inRFC 2119
> <https://tools.ietf.org/html/rfc2119>  [RFC2119
> <https://tools.ietf.org/html/rfc2119>].
> 
> 
> 
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> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-6>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> RSU: Road Side Unit.  A computer equipped with at least one IEEE 
> 802.11 interface operated in OCB mode.  This definition applies to 
> this document.  An RSU may be connected to the Internet, and may be 
> equipped with additional wired or wireless network interfaces
> running IP.  An RSU MAY be an IP Router.
> 
> 
> [Sri] RSU can be compared to an 802.11 access point; Or, WTP as
> defined in CAPWAP specification, RFC5415.
> 
> 
> Perhaps. rephrase as below?:
> 
> 
> "RSU: Road Side Unit. Its a wireless termination point (WTP), as
> defined in RFC5415 with one key difference, where the wireless
> physical and the mac layer is configured to operate in 802.11 OCB
> mode.  The RSU communicates with the On board Unit (OBU) in the
> vehicle over 802.11 wireless link operating in OCB mode.”
> 
> 
> 
> ** Also, since you are defining the RSU term, should you also not
> define OBU (On board Unit) in the vehicle which is the entity on the
> other end of the link? “RSU ----802.11-OCB——OBU” ? May be introduce
> the OCB definition separately, just as you did with RSU, and show the
>  communication link as 802.11-OCB.
> 
> 
> 
> OCB: outside the context of a basic service set (BSS): A mode of 
> operation in which a STA is not a member of a BSS and does not 
> utilize IEEE Std 802.11 authentication, association, or data 
> confidentiality.
> 
> 802.11-OCB, or 802.11 OCB: text in document IEEE 802.11-2012 that is 
> flagged by "dot11OCBActivated".  This means: IEEE 802.11e for
> quality of service; 802.11j-2004 for half-clocked operations; and
> (what was known earlier as) 802.11p for operation in the 5.9 GHz band
> and in mode OCB.
> 
> 
> [Sri] The text starting with. “This means” is not clear to me. Does
> it 802.11e is supported with 802.11OCB mode. Please clarify
> 
> 
> 
> 3 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-3>.
>
> 
Communication Scenarios where IEEE 802.11 OCB Links are Used
> 
> 
> 
> The IEEE 802.11 OCB Networks are used for vehicular communications, 
> as 'Wireless Access in Vehicular Environments'.  The IP
> communication scenarios for these environments have been described in
> several documents, among which we refer the reader to one recently
> updated [I-D.petrescu-its-scenarios-reqs 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-I-D.petrescu-its-scenarios-reqs>],
> about scenarios and requirements for IP in Intelligent Transportation
> Systems.
> 
> 
> [Sri] You can do bit more justice to this section.
> 
> Explain the link model. “STA ----802.11-OCB——STA”. Then talk about
> the applicability in Vehicular networks, with STA's as RSU and OCB.
> 
> You may also want to talk about, how links get formed/terminated; how
>  nodes peer/discover and how mobility works ..etc. While 802.11-OCB
> is clearly specified and the use of IPv6 over such link is also not 
> radically new, but the operating environment which is vehicular
> brings many new things. That description is not present any where.
> 
> 
> 4 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-4>.
>
> 
Aspects introduced by the OCB mode to 802.11
> 
> 
> 
> In the IEEE 802.11 OCB mode, all nodes in the wireless range can 
> directly communicate with each other without authentication/ 
> association procedures.  Briefly, the IEEE 802.11 OCB mode has the 
> following properties:
> 
> 
> 
> [Sri] Can you add some text on how nodes (ST1 and STA2) discover each
>  other on such links supporting 802.11 OCB mode.
> 
> o  The use by each node of a 'wildcard' BSSID (i.e., each bit of the 
> BSSID is set to 1)
> 
> o  No IEEE 802.11 Beacon frames transmitted
> 
> o  No authentication required
> 
> o  No association needed
> 
> o  No encryption provided
> 
> 
> [Sri] Can you clarify what you mean when you say “No xxx required” /
> “No xxx needed” for the above capabilities.  What does “needed” or 
> “required” mean? Does it mean, “Authentication", “Association" and 
> “Encryption” is optional on this link, or that its not supported on 
> 802.11 OCB links.
> 
> 
> o  Flag dot11OCBActivated set to true
> 
> The following message exchange diagram illustrates a comparison 
> between traditional 802.11 and 802.11 in OCB mode.  The 'Data'
> 
> 
> 
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>
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> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-7>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> messages can be IP messages such as the messages used in Stateless
> or Stateful Address Auto-Configuration, or other IP messages.
> 
> 
> 
> [Sri] Lets separatethe discussion on IP Address configuration using 
> SLAAC/DHCP on such links from the above description. The Data packets
>  here can be application packets such as HTTP or other packets. May
> be additional discussion is needed on the IP address configuration on
>  802.11-OCB links.
> 
> 
> 
> Other 802.11 management and control frames (non IP) may be
> transmitted, as specified in the 802.11 standard.  For information,
> the names of these messages as currently specified by the 802.11
> standard are listed inAppendix D 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-D>.
>
> 
> 
> 
> 
> 
> 
> STA                    AP              STA1                   STA2 |
> |               |                      | |<------ Beacon -------|
> |<------ Data -------->| |                      |               |
> | |---- Probe Req. ----->|               |<------ Data -------->| 
> |<--- Probe Res. ------|               |                      | |
> |               |<------ Data -------->| |---- Auth Req. ------>|
> |                      | |<--- Auth Res. -------|
> |<------ Data -------->| |                      |               |
> | |---- Asso Req. ------>|               |<------ Data -------->| 
> |<--- Asso Res. -------|               |                      | |
> |               |<------ Data -------->| |<------ Data -------->|
> |                      | |<------ Data -------->|
> |<------ Data -------->|
> 
> (a) 802.11 Infrastructure mode         (b) 802.11 OCB mode
> 
> 
> The link 802.11 OCB was specified in IEEE Std 802.11p (TM) -2010 
> [ieee802.11p-2010 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-ieee802.11p-2010>]
> as an amendment to IEEE Std 802.11 (TM) -2007, titled "Amendment 6:
> Wireless Access in Vehicular Environments". Since then, this
> amendment has been included in IEEE 802.11(TM)-2012 [ieee802.11-2012
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-ieee802.11-2012>],
> titled "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"; the
> modifications are diffused throughout various sections (e.g. the Time
> Advertisement message described in the earlier 802.11 (TM) p
> amendment is now described in section 'Frame formats', and the
> operation outside the context of a BSS described in section 'MLME').
> 
> In document 802.11-2012, specifically anything referring 
> "OCBActivated", or "outside the context of a basic service set" is 
> actually referring to the 802.11p aspects introduced to 802.11.
> Note that in earlier 802.11p documents the term "OCBEnabled" was
> used instead of te current "OCBActivated".
> 
> 
> 
> 
> 
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>
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> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-8>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> In order to delineate the aspects introduced by 802.11 OCB to
> 802.11, we refer to the earlier [ieee802.11p-2010 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-ieee802.11p-2010>].
> The amendment is concerned with vehicular communications, where the
> wireless link is similar to that of Wireless LAN (using a PHY layer
> specified by 802.11a/b/g/n), but which needs to cope with the high
> mobility factor inherent in scenarios of communications between
> moving vehicles, and between vehicles and fixed infrastructure
> deployed along roads. While 'p' is a letter just like 'a, b, g' and
> 'n' are, 'p' is concerned more with MAC modifications, and a little
> with PHY modifications; the others are mainly about PHY
> modifications.  It is possible in practice to combine a 'p' MAC with
> an 'a' PHY by operating outside the context of a BSS with OFDM at
> 5.4GHz.
> 
> The 802.11 OCB links are specified to be compatible as much as 
> possible with the behaviour of 802.11a/b/g/n and future generation 
> IEEE WLAN links.* From the IP perspective, an 802.11 OCB MAC layer
> offers practically the same interface to IP as the WiFi and Ethernet
> layers do (802.11a/b/g/n and 802.3).*
> 
> 
> [Sri] A packet sent from a vehicle’s OBU is received by a single RSU,
> or multiple RSU’s? How does the link-layer resolution happen?
> 
> 
> To support this similarity statement (IPv6 is layered on top of LLC 
> on top of 802.11 OCB similarly as on top of LLC on top of 
> 802.11a/b/g/n, and as on top of LLC on top of 802.3) it is useful to 
> analyze the differences between 802.11 OCB and 802.11
> specifications. Whereas the 802.11p amendment specifies relatively
> complex and numerous changes to the MAC layer (and very little to the
> PHY layer), we note there are only a few characteristics which may be
> important for an implementation transmitting IPv6 packets on 802.11
> OCB links.
> 
> In the list below, the only 802.11 OCB fundamental points which 
> influence IPv6 are the OCB operation and the 12Mbit/s maximum which 
> may be afforded by the IPv6 applications.
> 
> 
> [Sri] I am really not sure how link throughput (12Mbps) relates to
> "IPv6 support on OCB links".
> 
> 
> 
> o  Operation Outside the Context of a BSS (OCB): the (earlier 
> 802.11p) 802.11-OCB links are operated without a Basic Service Set 
> (BSS).  This means that the frames IEEE 802.11 Beacon, Association 
> Request/Response, Authentication Request/Response, and similar, are
> not used.  The used identifier of BSS (BSSID) has a hexadecimal value
> always 0xffffffffffff (48 '1' bits, represented as MAC address
> ff:ff:ff:ff:ff:ff, or otherwise the 'wildcard' BSSID), as opposed to
> an arbitrary BSSID value set by administrator (e.g.
> 'My-Home-AccessPoint').  The OCB operation - namely the lack of
> beacon-based scanning and lack of authentication - has a potentially
> strong impact on the use of the Mobile IPv6 protocol [RFC6275
> <https://tools.ietf.org/html/rfc6275>] and on the protocols for IP
> layer security [RFC4301 <https://tools.ietf.org/html/rfc4301>].
> 
> 
> [Sri] The document till now has been arguing heavily on how IPv6 
> operates so naturally on these links and now I see discussion on
> “Impact to a high-level protocol such as MIPv6”. You may want to fix
> the earlier text. In any case, the absence of link-layer security
> practically impacts every application, not just MIPv6. Also, MIPv6
> does not make any assumptions on the link-layer security. Also, the
> the 0xFF-FF-FF-FF-FF-FF as the BSSID, makes the messages readable by
> all other RSU’s in proximity. I think the discussion on the nature of
> the link, who all see’s the messages.. how L2 addresses are resolved
> is not explained clearly.
> 
> 
> 
> 
> o  Timing Advertisement: is a new message defined in 802.11-OCB, 
> which does not exist in 802.11a/b/g/n.  This message is used by
> 
> 
> 
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>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-9>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> stations to inform other stations about the value of time.  It is 
> similar to the time as delivered by a GNSS system (Galileo, GPS, ...)
> or by a cellular system.  This message is optional for 
> implementation.*At the date of writing, an experienced reviewer
> considers that currently no field testing has used this message.
> Another implementor considers this feature implemented in an initial
> manner. In the future, it is speculated that this message may be
> useful for very simple devices which may not have their own hardware
> source of time (Galileo, GPS, cellular network), or by vehicular
> devices situated in areas not covered by such network (in tunnels,
> underground, outdoors but shaded by foliage or buildings, in remote
> areas, etc.) *
> 
> 
> [Sri] The first part explaining Timing Advertisement messages is
> great, but the rest of the commentary is unnecessary and not needed.
> We don’t speculate the protocol adoption success in IETF
> specifications, or about the experience level of the “reviewer" :)
> 
> 
> 
> o  Frequency range: this is a characteristic of the PHY layer, with 
> almost no impact to the interface between MAC and IP.  However, it is
> worth considering that the frequency range is regulated by a regional
> authority (ARCEP, ETSI, FCC, etc.); as part of the regulation
> process, specific applications are associated with specific frequency
> ranges.  In the case of 802.11-OCB, the regulator associates a set of
> frequency ranges, or slots within a band, to the use of applications
> of vehicular communications, in a band known as "5.9GHz".  This band
> is "5.9GHz" which is different from the bands "2.4GHz" or "5GHz" used
> by Wireless LAN.  However, as with Wireless LAN, the operation of
> 802.11-OCB in "5.9GHz" bands is exempt from owning a license in EU
> (in US the 5.9GHz is a licensed band of spectrum; for the the fixed
> infrastructure an explicit FCC autorization is required; for an
> onboard device a 'licensed-by-rule' concept applies: rule
> certification conformity is required); however technical conditions
> are different than those of the bands "2.4GHz" or "5GHz".  On one
> hand, the allowed power levels, and implicitly the maximum allowed
> distance between vehicles, is of 33dBm for 802.11-OCB (in Europe),
> compared to 20 dBm for Wireless LAN 802.11a/b/g/n; this leads to a
> maximum distance of approximately 1km, compared to approximately 50m.
> On the other hand, specific conditions related to congestion 
> avoidance, jamming avoidance, and radar detection are imposed on the
> use of DSRC (in US) and on the use of frequencies for Intelligent
> Transportation Systems (in EU), compared to Wireless LAN
> (802.11a/b/g/n).
> 
> o  Prohibition of IPv6 on some channels relevant for IEEE
> 802.11-OCB, as opposed to IPv6 not being prohibited on any channel on
> which 802.11a/b/g/n runs:
> 
> *  Some channels are reserved for safety communications; the IPv6 
> packets should not be sent on these channels.
> 
> 
> 
> 
> 
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>
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> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-10>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> *  At the time of writing, the prohibition is explicit at higher 
> layer protocols providing services to the application; these higher
> layer protocols are specified in IEEE 1609 documents.
> 
> *  National or regional specifications and regulations specify the 
> use of different channels; these regulations must be followed.
> 
> o  'Half-rate' encoding: as the frequency range, this parameter is 
> related to PHY, and thus has not much impact on the interface between
> the IP layer and the MAC layer.
> 
> o  In vehicular communications using 802.11-OCB links, there are 
> strong privacy requirements with respect to addressing.  While the 
> 802.11-OCB standard does not specify anything in particular with 
> respect to MAC addresses, in these settings there exists a strong 
> need for dynamic change of these addresses (as opposed to the non- 
> vehicular settings - real wall protection - where fixed MAC addresses
> do not currently pose some privacy risks).  This is further described
> in sectionSection 7 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-7>.
> A relevant function is described in IEEE 1609.3-2016 [ieee1609.3 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-ieee1609.3>],
> clause 5.5.1 and IEEE 1609.4-2016 [ieee1609.4 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-ieee1609.4>],
> clause 6.7.
> 
> 
> Other aspects particular to 802.11-OCB which are also particular to 
> 802.11 (e.g. the 'hidden node' operation) may have an influence on 
> the use of transmission of IPv6 packets on 802.11-OCB networks.*The
> subnet structure which may be assumed in 802.11-OCB networks is 
> strongly influenced by the mobility of vehicles.*
> 
> 
> [Sri] Per my earlier comment, the link model, addressing ..etc needs
> to be explained in more detail. It is not clear what exactly the
> “subnet structure” that is assumed in 802.11-OCB.
> 
> 
> 5 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5>.
>
> 
Layering of IPv6 over 802.11-OCB as over Ethernet
> 
> 
> 
> 5.1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.1>.
>
> 
Maximum Transmission Unit (MTU)
> 
> 
> 
> The default MTU for IP packets on 802.11-OCB is 1500 octets.  It is 
> the same value as IPv6 packets on Ethernet links, as specified in 
> [RFC2464 <https://tools.ietf.org/html/rfc2464>].  This value of the
> MTU respects the recommendation that every link in the Internet must
> have a minimum MTU of 1280 octets (stated in [RFC2460
> <https://tools.ietf.org/html/rfc2460>], and the recommendations
> therein, especially with respect to fragmentation).  If IPv6 packets
> of size larger than 1500 bytes are sent on an 802.11-OCB interface
> card then the IP stack will fragment.  In case there are IP
> fragments, the field "Sequence number" of the 802.11 Data header
> containing the IP fragment field is increased.
> 
> Non-IP packets such as WAVE Short Message Protocol (WSMP) can be 
> delivered on 802.11-OCB links.  Specifications of these packets are 
> out of scope of this document, and do not impose any limit on the
> MTU size, allowing an arbitrary number of 'containers'.  Non-IP
> packets such as ETSI 'geonet' packets have an MTU of 1492 bytes.
> 
> 
> 
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>
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> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-11>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> The Equivalent Transmit Time on Channel is a concept that may be
> used as an alternative to the MTU concept.  A rate of transmission
> may be specified as well.  The ETTC, rate and MTU may be in direct 
> relationship.
> 
> [Sri] The last paragraph needs some additional context. Did
> 802.11-OCB introduce ETTC concept?
> 
> 
> 
> 
> 5.2 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.2>.
>
> 
Frame Format
> 
> 
> 
> IP packets are transmitted over 802.11-OCB as standard Ethernet 
> packets.  As with all 802.11 frames, an Ethernet adaptation layer is 
> used with 802.11-OCB as well.  This Ethernet Adaptation Layer 
> performing 802.11-to-Ethernet is described inSection 5.2.1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.2.1>.
> The Ethernet Type code (EtherType) for IPv6 is 0x86DD (hexadecimal
> 86DD, or otherwise #86DD).
> 
> The Frame format for transmitting IPv6 on 802.11-OCB networks is the 
> same as transmitting IPv6 on Ethernet networks, and is described in 
> section 3 of [RFC2464]
> <https://tools.ietf.org/html/rfc2464#section-3>.  The frame format
> for transmitting IPv6 packets over Ethernet is illustrated below:
> 
> 
> 0                   1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |          Destination          | 
> +-                             -+ |            Ethernet           | 
> +-                             -+ |            Address            | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |             Source            | 
> +-                             -+ |            Ethernet           | 
> +-                             -+ |            Address            | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1 0 0 0 0 1 1 0 1 1 0 1 1 1 0 1| 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |             IPv6              | 
> +-                             -+ |            header             | 
> +-                             -+ |             and               | 
> +-                             -+ /            payload ...        / 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ (Each tic mark represents one
> bit.)
> 
> 
> 
> 
> 
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>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-12>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> Ethernet II Fields:
> 
> Destination Ethernet Address the MAC destination address.
> 
> Source Ethernet Address the MAC source address.
> 
> 1 0 0 0 0 1 1 0 1 1 0 1 1 1 0 1 binary representation of the
> EtherType value 0x86DD.
> 
> IPv6 header and payload the IPv6 packet containing IPv6 header and
> payload.
> 
> 
> 5.2.1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.2.1>.
>
> 
Ethernet Adaptation Layer
> 
> 
> 
> In general, an 'adaptation' layer is inserted between a MAC layer
> and the Networking layer.  This is used to transform some parameters 
> between their form expected by the IP stack and the form provided by 
> the MAC layer.  For example, an 802.15.4 adaptation layer may
> perform fragmentation and reassembly operations on a MAC whose
> maximum Packet Data Unit size is smaller than the minimum MTU
> recognized by the IPv6 Networking layer.  Other examples involve
> link-layer address transformation, packet header insertion/removal,
> and so on.
> 
> An Ethernet Adaptation Layer makes an 802.11 MAC look to IP 
> Networking layer as a more traditional Ethernet layer.  At
> reception, this layer takes as input the IEEE 802.11 Data Header and
> the Logical-Link Layer Control Header and produces an Ethernet II
> Header. At sending, the reverse operation is performed.
> 
> 
> +--------------------+------------+-------------+---------+-----------+
>
> 
| 802.11 Data Header | LLC Header | IPv6 Header | Payload |.11 Trailer|
> +--------------------+------------+-------------+---------+-----------+
>
> 
\                               /                         \         /
> -----------------------------                             -------- 
> ^---------------------------------------------/ | 802.11-to-Ethernet
> Adaptation Layer | v +---------------------+-------------+---------+ 
> | Ethernet II Header  | IPv6 Header | Payload | 
> +---------------------+-------------+---------+
> 
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 12]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-13>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> The Receiver and Transmitter Address fields in the 802.11 Data
> Header contain the same values as the Destination and the Source
> Address fields in the Ethernet II Header, respectively.  The value of
> the Type field in the LLC Header is the same as the value of the
> Type field in the Ethernet II Header.
> 
> The ".11 Trailer" contains solely a 4-byte Frame Check Sequence.
> 
> The Ethernet Adaptation Layer performs operations in relation to IP 
> fragmentation and MTU.  One of these operations is briefly described 
> in sectionSection 5.1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.1>.
>
>  In OCB mode, IPv6 packets can be transmitted either as "IEEE 802.11 
> Data" or alternatively as "IEEE 802.11 QoS Data", as illustrated in 
> the following figure:
> 
> 
> +--------------------+-------------+-------------+---------+-----------+
>
> 
| 802.11 Data Header | LLC Header  | IPv6 Header | Payload |.11 Trailer|
> +--------------------+-------------+-------------+---------+-----------+
>
>  or
> 
> +--------------------+-------------+-------------+---------+-----------+
>
> 
| 802.11 QoS Data Hdr| LLC Header  | IPv6 Header | Payload |.11 Trailer|
> +--------------------+-------------+-------------+---------+-----------+
>
> 
> 
> The distinction between the two formats is given by the value of the 
> field "Type/Subtype".  The value of the field "Type/Subtype" in the 
> 802.11 Data header is 0x0020.  The value of the field "Type/Subtype" 
> in the 802.11 QoS header is 0x0028.
> 
> The mapping between qos-related fields in the IPv6 header (e.g. 
> "Traffic Class", "Flow label") and fields in the "802.11 QoS Data 
> Header" (e.g.  "QoS Control") are not specified in this document. 
> Guidance for a potential mapping is provided in 
> [I-D.ietf-tsvwg-ieee-802-11 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-I-D.ietf-tsvwg-ieee-802-11>],
> although it is not specific to OCB mode.
> 
> 
> 
> [Sri] The applicability of the QoS mapping draft to 802.11-OCB needs
>  further investigation, IMO.
> 
> 
> 
> 
> 5.3 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.3>.
>
> 
Link-Local Addresses
> 
> 
> 
> The link-local address of an 802.11-OCB interface is formed in the 
> same manner as on an Ethernet interface.  This manner is described
> in section 5 of [RFC2464]
> <https://tools.ietf.org/html/rfc2464#section-5>.
> 
> 
> 
> [Sri] Does this go against the 8064 recommendation on Interface 
> identifier generation?
> 
> May be RFC7217 for interface identifier generation in conjunction
> with the link-local address generation per RFC2464
> 
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 13]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-14>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> 5.4 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.4>.
>
> 
Address Mapping
> 
> 
> 
> For unicast as for multicast, there is no change from the unicast
> and multicast address mapping format of Ethernet interfaces, as
> defined by sections6 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-6>
> and7 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-7>
> of [RFC2464 <https://tools.ietf.org/html/rfc2464>].
> 
> 
> 
> [Sri] RFC6085 specified mapping is also relevant; If the
> communication peers are aware that there is only one peer, it should
> apply 6085 specified mapping. That mode is relevant for 802.11-OCB
> types links as well.
> 
> 
> 
> 5.4.1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.4.1>.
>
> 
Address Mapping -- Unicast
> 
> 
> 
> The procedure for mapping IPv6 unicast addresses into Ethernet link- 
> layer addresses is described in [RFC4861
> <https://tools.ietf.org/html/rfc4861>].  The Source/Target Link- 
> layer Address option has the following form when the link-layer is 
> Ethernet.
> 
> [Sri] I thought, mapping of IPv6 unicast addresses to Ethernet 
> link-layer addresses is specified in section 6, of RFC2464 and not in
>  RFC4861.
> 
> 
> 
> 
> 0                   1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |     Type      |    Length     | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |                               | 
> +-          Ethernet           -+ |                               | 
> +-           Address           -+ |                               | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> 
> Option fields:
> 
> Type 1 for Source Link-layer address. 2 for Target Link-layer
> address.
> 
> Length 1 (in units of 8 octets).
> 
> Ethernet Address The 48 bit Ethernet IEEE 802 address, in canonical
> bit order.
> 
> 
> 5.4.2 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.4.2>.
>
> 
Address Mapping -- Multicast
> 
> 
> 
> IPv6 protocols often make use of IPv6 multicast addresses in the 
> destination field of IPv6 headers.  For example, an ICMPv6 link- 
> scoped Neighbor Advertisement is sent to the IPv6 address ff02::1 
> denoted "all-nodes" address.  When transmitting these packets on 
> 802.11-OCB links it is necessary to map the IPv6 address to a MAC 
> address.
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 14]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-15>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> The same mapping requirement applies to the link-scoped multicast 
> addresses of other IPv6 protocols as well.  In DHCPv6, the 
> "All_DHCP_Servers" IPv6 multicast address ff02::1:2, and in OSPF the 
> "All_SPF_Routers" IPv6 multicast address ff02::5, need to be mapped 
> on a multicast MAC address.
> 
> An IPv6 packet with a multicast destination address DST, consisting 
> of the sixteen octets DST[1] through DST[16], is transmitted to the 
> IEEE 802.11-OCB MAC multicast address whose first two octets are the 
> value 0x3333 and whose last four octets are the last four octets of 
> DST.
> 
> [Sri] Please add a reference to Section 7, RFC4861 and also RFC6085.
> In general, for both unicast and multicast, you may want to clearly
> say that this is per the existing specs and duplicated here for
> convenience.
> 
> 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0 0 1 1 0 0 1 1|0 0 1 1 0 0 1 1| 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |   DST[13]     |   DST[14]     | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |   DST[15]     |   DST[16]     | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> 
> A Group ID TBD of length 112bits may be requested from IANA; this 
> Group ID signifies "All 80211OCB Interfaces Address".  Only the
> least 32 significant bits of this "All 80211OCB Interfaces Address"
> will be mapped to and from a MAC multicast address.
> 
> Transmitting IPv6 packets to multicast destinations over 802.11
> links proved to have some performance issues 
> [I-D.perkins-intarea-multicast-ieee802 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-I-D.perkins-intarea-multicast-ieee802>].
> These issues may be exacerbated in OCB mode.  Solutions for these
> problems should consider the OCB mode of operation.
> 
> 
> 5.5 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.5>.
>
> 
Stateless Autoconfiguration
> 
> 
> 
> The Interface Identifier for an 802.11-OCB interface is formed using 
> the same rules as the Interface Identifier for an Ethernet
> interface; this is described insection 4 of [RFC2464]
> <https://tools.ietf.org/html/rfc2464#section-4>.  No changes are
> needed, but some care must be taken when considering the use of the
> SLAAC procedure.
> 
> 
> 
> [Sri] Per my earlier comment, please refer to the current
> recommendation on interface-identifier generation and its use in
> link-local, global or other addresses.
> 
> The bits in the the interface identifier have no generic meaning and
> the identifier should be treated as an opaque value. The bits
> 'Universal' and 'Group' in the identifier of an 802.11-OCB interface
> are significant, as this is an IEEE link-layer address. The details
> of this significance are described in [I-D.ietf-6man-ug 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-I-D.ietf-6man-ug>].
>  Petrescu, et al. Expires February 18, 2018 [Page 15]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-16>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> As with all Ethernet and 802.11 interface identifiers ([RFC7721
> <https://tools.ietf.org/html/rfc7721>]), the identifier of an
> 802.11-OCB interface may involve privacy risks. A vehicle embarking
> an On-Board Unit whose egress interface is 802.11-OCB may expose
> itself to eavesdropping and subsequent correlation of data; this may
> reveal data considered private by the vehicle owner; there is a risk
> of being tracked; see the privacy considerations described inAppendix
> C 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C>.
>
> 
> 
> [Sri] I think there are other security issues here; the absence of 
> link-layer security opens up Mac-spoofing and IP address hijacking.
> That should be mentioned.
> 
> 
> 
> If stable Interface Identifiers are needed in order to form IPv6 
> addresses on 802.11-OCB links, it is recommended to follow the 
> recommendation in [I-D.ietf-6man-default-iids 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#ref-I-D.ietf-6man-default-iids>].
>
> 
> 
> 5.6 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-5.6>.
>
> 
Subnet Structure
> 
> 
> 
> The 802.11 networks in OCB mode may be considered as 'ad-hoc' 
> networks.  The addressing model for such networks is described in 
> [RFC5889 <https://tools.ietf.org/html/rfc5889>].
> 
> 
> [Sri] Per my earlier comment, there is no system level view of the 
> network where 802.11-OCB links are used. So, in the absence of such 
> discussion So, I am not sure what part of RFC5889 is applicable here.
>  For example, link-local addresses may just work fine.
> 
> 
> 
> 6 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-6>.
>
> 
Example IPv6 Packet captured over a IEEE 802.11-OCB link
> 
> 
> 
> We remind that a main goal of this document is to make the case that 
> IPv6 works fine over 802.11-OCB networks.  Consequently, this
> section is an illustration of this concept and thus can help the
> implementer when it comes to running IPv6 over IEEE 802.11-OCB.  By
> way of example we show that there is no modification in the headers
> when transmitted over 802.11-OCB networks - they are transmitted like
> any other 802.11 and Ethernet packets.
> 
> We describe an experiment of capturing an IPv6 packet on an 
> 802.11-OCB link.  In this experiment, the packet is an IPv6 Router 
> Advertisement.  This packet is emitted by a Router on its 802.11-OCB 
> interface.  The packet is captured on the Host, using a network 
> protocol analyzer (e.g.  Wireshark); the capture is performed in two 
> different modes: direct mode and 'monitor' mode.  The topology used 
> during the capture is depicted below.
> 
> 
> +--------+                                +-------+ |        |
> 802.11-OCB Link         |       | ---| Router
> |--------------------------------| Host  | |        |
> |       | +--------+                                +-------+
> 
> 
> During several capture operations running from a few moments to 
> several hours, no message relevant to the BSSID contexts were 
> captured (no Association Request/Response, Authentication Req/Resp,
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 16]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-17>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> Beacon).  This shows that the operation of 802.11-OCB is outside the 
> context of a BSSID.
> 
> Overall, the captured message is identical with a capture of an IPv6 
> packet emitted on a 802.11b interface.  The contents are precisely 
> similar.
> 
> 
> [Sri] I suggest moving this discussion under the section
> “Implementation Status”, which will eventually be removed from the
> RFC. There is nothing new here. This are details on experimentation.
> But, if you think there is some useful information such as discussion
> on Capture mode ..etc, you may want to move this entire section to
> Appendix. Implementors may use these tools for verification.
> 
> 
> 
> 
> 6.1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-6.1>.
>
> 
Capture in Monitor Mode
> 
> 
> 
> The IPv6 RA packet captured in monitor mode is illustrated below. The
> radio tap header provides more flexibility for reporting the 
> characteristics of frames.  The Radiotap Header is prepended by this 
> particular stack and operating system on the Host machine to the RA 
> packet received from the network (the Radiotap Header is not present 
> on the air).  The implementation-dependent Radiotap Header is useful 
> for piggybacking PHY information from the chip's registers as data
> in a packet understandable by userland applications using Socket 
> interfaces (the PHY interface can be, for example: power levels,
> data rate, ratio of signal to noise).
> 
> The packet present on the air is formed by IEEE 802.11 Data Header, 
> Logical Link Control Header, IPv6 Base Header and ICMPv6 Header.
> 
> 
> 
> Radiotap Header v0 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |Header Revision|  Header Pad   |    Header length              | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Present flags                         | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Data Rate     |             Pad                               | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> IEEE 802.11 Data Header 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Type/Subtype and Frame Ctrl  |          Duration             | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Receiver Address... 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ...
> Receiver Address           |      Transmitter Address... 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ...
> Transmitter Address                                        | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> BSS Id... 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ...
> BSS Id                     |  Frag Number and Seq Number   | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 17]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-18>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> Logical-Link Control Header 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> DSAP   |I|     SSAP    |C| Control field | Org. code... 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ...
> Organizational Code        |             Type              | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> IPv6 Base Header 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |Version| Traffic Class |           Flow Label                  | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Payload Length        |  Next Header  |   Hop Limit   | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> | +                                                               + |
> | +                         Source Address                        + |
> | +                                                               + |
> | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> | +                                                               + |
> | +                      Destination Address                      + |
> | +                                                               + |
> | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> Router Advertisement 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Type      |     Code      |          Checksum             | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Cur Hop Limit |M|O|  Reserved |       Router Lifetime         | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Reachable Time                        | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Retrans Timer                        | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Options ... +-+-+-+-+-+-+-+-+-+-+-+-
> 
> 
> The value of the Data Rate field in the Radiotap header is set to 6 
> Mb/s.  This indicates the rate at which this RA was received.
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 18]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-19>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> The value of the Transmitter address in the IEEE 802.11 Data Header 
> is set to a 48bit value.  The value of the destination address is 
> 33:33:00:00:00:1 (all-nodes multicast address).  The value of the
> BSS Id field is ff:ff:ff:ff:ff:ff, which is recognized by the
> network protocol analyzer as being "broadcast".  The Fragment number
> and sequence number fields are together set to 0x90C6.
> 
> The value of the Organization Code field in the Logical-Link Control 
> Header is set to 0x0, recognized as "Encapsulated Ethernet".  The 
> value of the Type field is 0x86DD (hexadecimal 86DD, or otherwise 
> #86DD), recognized as "IPv6".
> 
> A Router Advertisement is periodically sent by the router to 
> multicast group address ff02::1.  It is an icmp packet type 134.
> The IPv6 Neighbor Discovery's Router Advertisement message contains
> an 8-bit field reserved for single-bit flags, as described in
> [RFC4861 <https://tools.ietf.org/html/rfc4861>].
> 
> The IPv6 header contains the link local address of the router 
> (source) configured via EUI-64 algorithm, and destination address
> set to ff02::1.  Recent versions of network protocol analyzers (e.g. 
> Wireshark) provide additional informations for an IP address, if a 
> geolocalization database is present.  In this example, the 
> geolocalization database is absent, and the "GeoIP" information is 
> set to unknown for both source and destination addresses (although 
> the IPv6 source and destination addresses are set to useful values). 
> This "GeoIP" can be a useful information to look up the city, 
> country, AS number, and other information for an IP address.
> 
> 
> [Sri] Not sure, why all of this text should be in the specification.
> 
> 
> The Ethernet Type field in the logical-link control header is set to 
> 0x86dd which indicates that the frame transports an IPv6 packet.  In 
> the IEEE 802.11 data, the destination address is 33:33:00:00:00:01 
> which is he corresponding multicast MAC address.  The BSS id is a 
> broadcast address of ff:ff:ff:ff:ff:ff.  Due to the short link 
> duration between vehicles and the roadside infrastructure, there is 
> no need in IEEE 802.11-OCB to wait for the completion of association 
> and authentication procedures before exchanging data.  IEEE 
> 802.11-OCB enabled nodes use the wildcard BSSID (a value of all 1s) 
> and may start communicating as soon as they arrive on the 
> communication channel.
> 
> 
> 6.2 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-6.2>.
>
> 
Capture in Normal Mode
> 
> 
> 
> The same IPv6 Router Advertisement packet described above (monitor 
> mode) is captured on the Host, in the Normal mode, and depicted 
> below.
> 
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 19]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-20>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> Ethernet II Header 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Destination... 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> ...Destination                 |           Source... 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> ...Source                                                      | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Type                 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> IPv6 Base Header 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
> |Version| Traffic Class |           Flow Label                  | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Payload Length        |  Next Header  |   Hop Limit   | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> | +                                                               + |
> | +                         Source Address                        + |
> | +                                                               + |
> | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> | +                                                               + |
> | +                      Destination Address                      + |
> | +                                                               + |
> | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> 
> Router Advertisement 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Type      |     Code      |          Checksum             | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Cur Hop Limit |M|O|  Reserved |       Router Lifetime         | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Reachable Time                        | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Retrans Timer                        | 
> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
> Options ... +-+-+-+-+-+-+-+-+-+-+-+-
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 20]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-21>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> One notices that the Radiotap Header is not prepended, and that the 
> IEEE 802.11 Data Header and the Logical-Link Control Headers are not 
> present.  On another hand, a new header named Ethernet II Header is 
> present.
> 
> The Destination and Source addresses in the Ethernet II header 
> contain the same values as the fields Receiver Address and 
> Transmitter Address present in the IEEE 802.11 Data Header in the 
> "monitor" mode capture.
> 
> The value of the Type field in the Ethernet II header is 0x86DD 
> (recognized as "IPv6"); this value is the same value as the value of 
> the field Type in the Logical-Link Control Header in the "monitor" 
> mode capture.
> 
> The knowledgeable experimenter will no doubt notice the similarity
> of this Ethernet II Header with a capture in normal mode on a pure 
> Ethernet cable interface.
> 
> It may be interpreted that an Adaptation layer is inserted in a pure 
> IEEE 802.11 MAC packets in the air, before delivering to the 
> applications.  In detail, this adaptation layer may consist in 
> elimination of the Radiotap, 802.11 and LLC headers and insertion of 
> the Ethernet II header.  In this way, it can be stated that IPv6
> runs naturally straight over LLC over the 802.11-OCB MAC layer, as
> shown by the use of the Type 0x86DD, and assuming an adaptation
> layer (adapting 802.11 LLC/MAC to Ethernet II header).
> 
> 
> 7 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-7>.
>
> 
Security Considerations
> 
> 
> 
> Any security mechanism at the IP layer or above that may be carried 
> out for the general case of IPv6 may also be carried out for IPv6 
> operating over 802.11-OCB.
> 
> 
> 802.11-OCB does not provide any cryptographic protection, because it 
> operates outside the context of a BSS (no Association Request/ 
> Response, no Challenge messages).  Any attacker can therefore just 
> sit in the near range of vehicles, sniff the network (just set the 
> interface card's frequency to the proper range) and perform attacks 
> without needing to physically break any wall.  Such a link is way 
> less protected than commonly used links (wired link or protected 
> 802.11).
> 
> [Sri] Per my earlier comment, there is more than one attack vector
> possible
> 
> 1.) Absence of link-layer security and the potential for mac address
>  spoofing
> 
> 2.) IP address / Session hijacking
> 
> 3.) Data privacy per your text
> 
> 
> 
> At the IP layer, IPsec can be used to protect unicast
> communications, and SeND can be used for multicast communications.
> 
> 
> [Sri] IPSec can be used for protecting both multicast or unicast 
> communication; RFC-5374 with GDOI.
> 
> 
> 
> 
> If no protection is used by the IP layer, upper layers should be
> protected. Otherwise, the end-user or system should be warned about
> the risks they run.
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 21]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-22>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> As with all Ethernet and 802.11 interface identifiers, there may 
> exist privacy risks in the use of 802.11-OCB interface identifiers. 
> Moreover, in outdoors vehicular settings, the privacy risks are more 
> important than in indoors settings.  New risks are induced by the 
> possibility of attacker sniffers deployed along routes which listen 
> for IP packets of vehicles passing by.  For this reason, in the 
> 802.11-OCB deployments, there is a strong necessity to use
> protection tools such as dynamically changing MAC addresses.  This
> may help mitigate privacy risks to a certain level.  On another hand,
> it may have an impact in the way typical IPv6 address
> auto-configuration is performed for vehicles (SLAAC would rely on MAC
> addresses amd would hence dynamically change the affected IP
> address), in the way the IPv6 Privacy addresses were used, and other
> effects.
> 
> 
> 8 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-8>.
>
> 
IANA Considerations
> 
> 
> 
> 9 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-9>.
>
> 
Contributors
> 
> 
> 
> Romain Kuntz contributed extensively about IPv6 handovers between 
> links running outside the context of a BSS (802.11-OCB links).
> 
> Tim Leinmueller contributed the idea of the use of IPv6 over 
> 802.11-OCB for distribution of certificates.
> 
> Marios Makassikis, Jose Santa Lozano, Albin Severinson and Alexey 
> Voronov provided significant feedback on the experience of using IP 
> messages over 802.11-OCB in initial trials.
> 
> Michelle Wetterwald contributed extensively the MTU discussion, 
> offered the ETSI ITS perspective, and reviewed other parts of the 
> document.
> 
> 
> 10 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-10>.
>
> 
Acknowledgements
> 
> 
> 
> The authors would like to thank Witold Klaudel, Ryuji Wakikawa, 
> Emmanuel Baccelli, John Kenney, John Moring, Francois Simon, Dan 
> Romascanu, Konstantin Khait, Ralph Droms, Richard 'Dick' Roy, Ray 
> Hunter, Tom Kurihara, Michal Sojka, Jan de Jongh, Suresh Krishnan, 
> Dino Farinacci, Vincent Park, Jaehoon Paul Jeong, Gloria Gwynne, 
> Hans-Joachim Fischer, Russ Housley, Rex Buddenberg, Erik Nordmark, 
> Bob Moskowitz, Andrew (Dryden?), Georg Mayer, Dorothy Stanley and 
> William Whyte.  Their valuable comments clarified certain issues and 
> generally helped to improve the document.
> 
> Pierre Pfister, Rostislav Lisovy, and others, wrote 802.11-OCB 
> drivers for linux and described how.
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 22]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-23>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> For the multicast discussion, the authors would like to thank Owen 
> DeLong, Joe Touch, Jen Linkova, Erik Kline, Brian Haberman and 
> participants to discussions in network working groups.
> 
> The authours would like to thank participants to the Birds-of- 
> a-Feather "Intelligent Transportation Systems" meetings held at IETF 
> in 2016.
> 
> 
> 11 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-11>.
>
> 
References
> 
> 
> 
> 11.1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-11.1>.
>
> 
Normative References
> 
> 
> 
> [I-D.ietf-6man-default-iids] Gont, F., Cooper, A., Thaler, D., and S.
> LIU, "Recommendation on Stable IPv6 Interface Identifiers", 
> draft-ietf-6man-default-iids-16 
> <https://tools.ietf.org/html/draft-ietf-6man-default-iids-16>  (work
> in progress), September 2016.
> 
> [I-D.ietf-6man-ug] Carpenter, B. and S. Jiang, "Significance of IPv6 
> Interface Identifiers",draft-ietf-6man-ug-06
> <https://tools.ietf.org/html/draft-ietf-6man-ug-06>  (work in 
> progress), December 2013.
> 
> [I-D.ietf-tsvwg-ieee-802-11] Szigeti, T., Henry, J., and F. Baker,
> "Diffserv to IEEE 802.11 Mapping",draft-ietf-tsvwg-ieee-802-11-06 
> <https://tools.ietf.org/html/draft-ietf-tsvwg-ieee-802-11-06>  (work
> in progress), August 2017.
> 
> [RFC1042]  Postel, J. and J. Reynolds, "Standard for the
> transmission of IP datagrams over IEEE 802 networks", STD 43,RFC 1042
> <https://tools.ietf.org/html/rfc1042>, DOI 10.17487/RFC1042, February
> 1988, <https://www.rfc- <https://www.rfc-editor.org/info/rfc1042> 
> editor.org/info/rfc1042 <https://www.rfc-editor.org/info/rfc1042>>.
> 
> [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate 
> Requirement Levels",BCP 14 <https://tools.ietf.org/html/bcp14>,RFC
> 2119 <https://tools.ietf.org/html/rfc2119>, DOI 10.17487/RFC2119,
> March 1997, <https://www.rfc-
> <https://www.rfc-editor.org/info/rfc2119> editor.org/info/rfc2119
> <https://www.rfc-editor.org/info/rfc2119>>.
> 
> [RFC2460]  Deering, S. and R. Hinden, "Internet Protocol, Version 6 
> (IPv6) Specification",RFC 2460 <https://tools.ietf.org/html/rfc2460>,
> DOI 10.17487/RFC2460, December 1998,
> <https://www.rfc-editor.org/info/rfc2460>.
> 
> [RFC2464]  Crawford, M., "Transmission of IPv6 Packets over Ethernet 
> Networks",RFC 2464 <https://tools.ietf.org/html/rfc2464>, DOI
> 10.17487/RFC2464, December 1998, 
> <https://www.rfc-editor.org/info/rfc2464>.
> 
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 23]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-24>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> [RFC3963]  Devarapalli, V., Wakikawa, R., Petrescu, A., and P. 
> Thubert, "Network Mobility (NEMO) Basic Support Protocol", RFC 3963
> <https://tools.ietf.org/html/rfc3963>, DOI 10.17487/RFC3963, January
> 2005, <https://www.rfc-editor.org/info/rfc3963>.
> 
> [RFC4086]  Eastlake 3rd, D., Schiller, J., and S. Crocker, 
> "Randomness Requirements for Security",BCP 106
> <https://tools.ietf.org/html/bcp106>,RFC 4086
> <https://tools.ietf.org/html/rfc4086>, DOI 10.17487/RFC4086, June
> 2005, <https://www.rfc- <https://www.rfc-editor.org/info/rfc4086> 
> editor.org/info/rfc4086 <https://www.rfc-editor.org/info/rfc4086>>.
> 
> [RFC4301]  Kent, S. and K. Seo, "Security Architecture for the 
> Internet Protocol",RFC 4301 <https://tools.ietf.org/html/rfc4301>,
> DOI 10.17487/RFC4301, December 2005,
> <https://www.rfc-editor.org/info/rfc4301>.
> 
> [RFC4429]  Moore, N., "Optimistic Duplicate Address Detection (DAD) 
> for IPv6",RFC 4429 <https://tools.ietf.org/html/rfc4429>, DOI
> 10.17487/RFC4429, April 2006, 
> <https://www.rfc-editor.org/info/rfc4429>.
> 
> [RFC4861]  Narten, T., Nordmark, E., Simpson, W., and H. Soliman, 
> "Neighbor Discovery for IP version 6 (IPv6)",RFC 4861
> <https://tools.ietf.org/html/rfc4861>, DOI 10.17487/RFC4861,
> September 2007, <https://www.rfc-
> <https://www.rfc-editor.org/info/rfc4861> editor.org/info/rfc4861
> <https://www.rfc-editor.org/info/rfc4861>>.
> 
> [RFC5889]  Baccelli, E., Ed. and M. Townsley, Ed., "IP Addressing 
> Model in Ad Hoc Networks",RFC 5889
> <https://tools.ietf.org/html/rfc5889>, DOI 10.17487/RFC5889, 
> September 2010, <https://www.rfc-editor.org/info/rfc5889>.
> 
> [RFC6275]  Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility 
> Support in IPv6",RFC 6275 <https://tools.ietf.org/html/rfc6275>, DOI
> 10.17487/RFC6275, July 2011,
> <https://www.rfc-editor.org/info/rfc6275>.
> 
> [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
> <https://tools.ietf.org/html/rfc6775>, DOI 10.17487/RFC6775, November
> 2012, <https://www.rfc-editor.org/info/rfc6775>.
> 
> [RFC7721]  Cooper, A., Gont, F., and D. Thaler, "Security and
> Privacy Considerations for IPv6 Address Generation Mechanisms", RFC
> 7721 <https://tools.ietf.org/html/rfc7721>, DOI 10.17487/RFC7721,
> March 2016, <https://www.rfc-editor.org/info/rfc7721>.
> 
> 
> 11.2 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#section-11.2>.
>
> 
Informative References
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 24]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-25>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> [fcc-cc]   "'Report and Order, Before the Federal Communications 
> Commission Washington, D.C. 20554', FCC 03-324, Released on February
> 10, 2004, document FCC-03-324A1.pdf, document freely available at
> URL http://www.its.dot.gov/exit/fcc_edocs.htm  downloaded on October
> 17th, 2013.".
> 
> [fcc-cc-172-184] "'Memorandum Opinion and Order, Before the Federal 
> Communications Commission Washington, D.C. 20554', FCC 06-10,
> Released on July 26, 2006, document FCC- 06-110A1.pdf, document
> freely available at URL 
> http://hraunfoss.fcc.gov/edocs_public/attachmatch/ 
> <http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-06-110A1.pdf> 
> FCC-06-110A1.pdf 
> <http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-06-110A1.pdf>
> downloaded on June 5th, 2014.".
> 
> [I-D.jeong-ipwave-vehicular-networking-survey] Jeong, J., Cespedes,
> S., Benamar, N., Haerri, J., and M. Wetterwald, "Survey on IP-based
> Vehicular Networking for Intelligent Transportation
> Systems",draft-jeong-ipwave- 
> <https://tools.ietf.org/html/draft-jeong-ipwave-vehicular-networking-survey-03>
>
> 
vehicular-networking-survey-03
> <https://tools.ietf.org/html/draft-jeong-ipwave-vehicular-networking-survey-03>
> (work in progress), June 2017.
> 
> [I-D.perkins-intarea-multicast-ieee802] Perkins, C., Stanley, D.,
> Kumari, W., and J. Zuniga, "Multicast Considerations over IEEE 802
> Wireless Media", draft-perkins-intarea-multicast-ieee802-03 
> <https://tools.ietf.org/html/draft-perkins-intarea-multicast-ieee802-03>
> (work in progress), July 2017.
> 
> [I-D.petrescu-its-scenarios-reqs] Petrescu, A., Janneteau, C., Boc,
> M., and W. Klaudel, "Scenarios and Requirements for IP in
> Intelligent Transportation Systems",draft-petrescu-its-scenarios- 
> <https://tools.ietf.org/html/draft-petrescu-its-scenarios-reqs-03> 
> reqs-03
> <https://tools.ietf.org/html/draft-petrescu-its-scenarios-reqs-03>
> (work in progress), October 2013.
> 
> [ieee1609.2] "IEEE SA - 1609.2-2016 - IEEE Standard for Wireless
> Access in Vehicular Environments (WAVE) -- Security Services for 
> Applications and Management Messages.  Example URL 
> http://ieeexplore.ieee.org/document/7426684/  accessed on August
> 17th, 2017.".
> 
> [ieee1609.3] "IEEE SA - 1609.3-2016 - IEEE Standard for Wireless
> Access in Vehicular Environments (WAVE) -- Networking Services. 
> Example URLhttp://ieeexplore.ieee.org/document/7458115/ 
> <http://ieeexplore.ieee.org/document/7458115/accessed> accessed
> <http://ieeexplore.ieee.org/document/7458115/accessed>  on August
> 17th, 2017.".
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 25]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-26>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> [ieee1609.4] "IEEE SA - 1609.4-2016 - IEEE Standard for Wireless
> Access in Vehicular Environments (WAVE) -- Multi-Channel Operation.
> Example URL http://ieeexplore.ieee.org/document/7435228/  accessed
> on August 17th, 2017.".
> 
> [ieee802.11-2012] "802.11-2012 - 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.  Downloaded on October 17th, 2013, from IEEE
> Standards, document freely available at URL 
> http://standards.ieee.org/findstds/ 
> <http://standards.ieee.org/findstds/standard/802.11-2012.html> 
> standard/802.11-2012.html 
> <http://standards.ieee.org/findstds/standard/802.11-2012.html>
> retrieved on October 17th, 2013.".
> 
> [ieee802.11p-2010] "IEEE Std 802.11p (TM)-2010, 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: Wireless Access in
> Vehicular Environments; document freely available at URL 
> http://standards.ieee.org/getieee802/ 
> <http://standards.ieee.org/getieee802/download/802.11p-2010.pdf> 
> download/802.11p-2010.pdf 
> <http://standards.ieee.org/getieee802/download/802.11p-2010.pdf>
> retrieved on September 20th, 2013.".
> 
> 
> Appendix A 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-A>.
>
> 
ChangeLog
> 
> 
> 
> The changes are listed in reverse chronological order, most recent 
> changes appearing at the top of the list.
> 
> Fromdraft-ietf-ipwave-ipv6-over-80211ocb-03 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-03>
> todraft-ietf-ipwave- 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04>
>
> 
ipv6-over-80211ocb-04
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04>
>
>  o  Removed a few informative references pointing to Dx draft IEEE 
> 1609 documents.
> 
> o  Removed outdated informative references to ETSI documents.
> 
> o  Added citations to IEEE 1609.2, .3 and .4-2016.
> 
> o  Minor textual issues.
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 26]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-27>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> Fromdraft-ietf-ipwave-ipv6-over-80211ocb-02 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-02>
> todraft-ietf-ipwave- 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-03>
>
> 
ipv6-over-80211ocb-03
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-03>
>
>  o  Keep the previous text on multiple addresses, so remove talk
> about MIP6, NEMOv6 and MCoA.
> 
> o  Clarified that a 'Beacon' is an IEEE 802.11 frame Beacon.
> 
> o  Clarified the figure showing Infrastructure mode and OCB mode
> side by side.
> 
> o  Added a reference to the IP Security Architecture RFC.
> 
> o  Detailed the IPv6-per-channel prohibition paragraph which
> reflects the discussion at the last IETF IPWAVE WG meeting.
> 
> o  Added section "Address Mapping -- Unicast".
> 
> o  Added the ".11 Trailer" to pictures of 802.11 frames.
> 
> o  Added text about SNAP carrying the Ethertype.
> 
> o  New RSU definition allowing for it be both a Router and not 
> necessarily a Router some times.
> 
> o  Minor textual issues.
> 
> Fromdraft-ietf-ipwave-ipv6-over-80211ocb-01 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-01>
> todraft-ietf-ipwave- 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-02>
>
> 
ipv6-over-80211ocb-02
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-02>
>
>  o  Replaced almost all occurences of 802.11p with 802.11-OCB,
> leaving only when explanation of evolution was necessary.
> 
> o  Shortened by removing parameter details from a paragraph in the 
> Introduction.
> 
> o  Moved a reference from Normative to Informative.
> 
> o  Added text in intro clarifying there is no handover spec at IEEE, 
> and that 1609.2 does provide security services.
> 
> o  Named the contents the fields of the EthernetII header (including 
> the Ethertype bitstring).
> 
> o  Improved relationship between two paragraphs describing the 
> increase of the Sequence Number in 802.11 header upon IP 
> fragmentation.
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 27]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-28>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> o  Added brief clarification of "tracking".
> 
> Fromdraft-ietf-ipwave-ipv6-over-80211ocb-00 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-00>
> todraft-ietf-ipwave- 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-01>
>
> 
ipv6-over-80211ocb-01
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-01>
>
>  o  Introduced message exchange diagram illustrating differences 
> between 802.11 and 802.11 in OCB mode.
> 
> o  Introduced an appendix listing for information the set of 802.11 
> messages that may be transmitted in OCB mode.
> 
> o  Removed appendix sections "Privacy Requirements", "Authentication 
> Requirements" and "Security Certificate Generation".
> 
> o  Removed appendix section "Non IP Communications".
> 
> o  Introductory phrase in the Security Considerations section.
> 
> o  Improved the definition of "OCB".
> 
> o  Introduced theoretical stacked layers about IPv6 and IEEE layers 
> including EPD.
> 
> o  Removed the appendix describing the details of prohibiting IPv6
> on certain channels relevant to 802.11-OCB.
> 
> o  Added a brief reference in the privacy text about a precise
> clause in IEEE 1609.3 and .4.
> 
> o  Clarified the definition of a Road Side Unit.
> 
> o  Removed the discussion about security of WSA (because is non-IP).
> 
> o  Removed mentioning of the GeoNetworking discussion.
> 
> o  Moved references to scientific articles to a separate 'overview' 
> draft, and referred to it.
> 
> 
> Appendix B 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-B>.
>
> 
Changes Needed on a software driver 802.11a to become a
> 
> 
> 802.11-OCB driver
> 
> The 802.11p amendment modifies both the 802.11 stack's physical and 
> MAC layers but all the induced modifications can be quite easily 
> obtained by modifying an existing 802.11a ad-hoc stack.
> 
> Conditions for a 802.11a hardware to be 802.11-OCB compliant:
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 28]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-29>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> o  The chip must support the frequency bands on which the regulator 
> recommends the use of ITS communications, for example using IEEE 
> 802.11-OCB layer, in France: 5875MHz to 5925MHz.
> 
> o  The chip must support the half-rate mode (the internal clock 
> should be able to be divided by two).
> 
> o  The chip transmit spectrum mask must be compliant to the
> "Transmit spectrum mask" from the IEEE 802.11p amendment (but
> experimental environments tolerate otherwise).
> 
> o  The chip should be able to transmit up to 44.8 dBm when used by 
> the US government in the United States, and up to 33 dBm in Europe;
> other regional conditions apply.
> 
> Changes needed on the network stack in OCB mode:
> 
> o  Physical layer:
> 
> *  The chip must use the Orthogonal Frequency Multiple Access (OFDM)
> encoding mode.
> 
> *  The chip must be set in half-mode rate mode (the internal clock 
> frequency is divided by two).
> 
> *  The chip must use dedicated channels and should allow the use of
> higher emission powers.  This may require modifications to the
> regulatory domains rules, if used by the kernel to enforce local
> specific restrictions.  Such modifications must respect the
> location-specific laws.
> 
> MAC layer:
> 
> *  All management frames (beacons, join, leave, and others) emission
> and reception must be disabled except for frames of subtype Action
> and Timing Advertisement (defined below).
> 
> *  No encryption key or method must be used.
> 
> *  Packet emission and reception must be performed as in ad-hoc mode,
> using the wildcard BSSID (ff:ff:ff:ff:ff:ff).
> 
> *  The functions related to joining a BSS (Association Request/ 
> Response) and for authentication (Authentication Request/Reply, 
> Challenge) are not called.
> 
> *  The beacon interval is always set to 0 (zero).
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 29]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-30>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> *  Timing Advertisement frames, defined in the amendment, should be
> supported.  The upper layer should be able to trigger such frames
> emission and to retrieve information contained in received Timing
> Advertisements.
> 
> 
> Appendix C 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C>.
>
> 
Design Considerations
> 
> 
> 
> The networks defined by 802.11-OCB are in many ways similar to other 
> networks of the 802.11 family.  In theory, the encapsulation of IPv6 
> over 802.11-OCB could be very similar to the operation of IPv6 over 
> other networks of the 802.11 family.  However, the high mobility, 
> strong link asymetry and very short connection makes the 802.11-OCB 
> link significantly different from other 802.11 networks.  Also, the 
> automotive applications have specific requirements for reliability, 
> security and privacy, which further add to the particularity of the 
> 802.11-OCB link.
> 
> 
> C.1 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C.1>.
>
> 
Vehicle ID
> 
> 
> 
> Automotive networks require the unique representation of each of 
> their node.  Accordingly, a vehicle must be identified by at least 
> one unique identifier.  The current specification at ETSI and at
> IEEE 1609 identifies a vehicle by its MAC address uniquely obtained
> from the 802.11-OCB NIC.
> 
> A MAC address uniquely obtained from a IEEE 802.11-OCB NIC 
> implicitely generates multiple vehicle IDs in case of multiple 
> 802.11-OCB NICs.  A mechanims to uniquely identify a vehicle 
> irrespectively to the different NICs and/or technologies is
> required.
> 
> 
> C.2 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C.2>.
>
> 
Reliability Requirements
> 
> 
> 
> The dynamically changing topology, short connectivity, mobile 
> transmitter and receivers, different antenna heights, and many-to- 
> many communication types, make IEEE 802.11-OCB links significantly 
> different from other IEEE 802.11 links.  Any IPv6 mechanism
> operating on IEEE 802.11-OCB link MUST support strong link asymetry,
> spatio- temporal link quality, fast address resolution and
> transmission.
> 
> IEEE 802.11-OCB strongly differs from other 802.11 systems to
> operate outside of the context of a Basic Service Set.  This means
> in practice that IEEE 802.11-OCB does not rely on a Base Station for
> all Basic Service Set management.  In particular, IEEE 802.11-OCB
> SHALL NOT use beacons.  Any IPv6 mechanism requiring L2 services from
> IEEE 802.11 beacons MUST support an alternative service.
> 
> 
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 30]
> 
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>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-31>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> Channel scanning being disabled, IPv6 over IEEE 802.11-OCB MUST 
> implement a mechanism for transmitter and receiver to converge to a 
> common channel.
> 
> Authentication not being possible, IPv6 over IEEE 802.11-OCB MUST 
> implement an distributed mechanism to authenticate transmitters and 
> receivers without the support of a DHCP server.
> 
> Time synchronization not being available, IPv6 over IEEE 802.11-OCB 
> MUST implement a higher layer mechanism for time synchronization 
> between transmitters and receivers without the support of a NTP 
> server.
> 
> The IEEE 802.11-OCB link being asymetic, IPv6 over IEEE 802.11-OCB 
> MUST disable management mechanisms requesting acknowledgements or 
> replies.
> 
> The IEEE 802.11-OCB link having a short duration time, IPv6 over
> IEEE 802.11-OCB MUST implement fast IPv6 mobility management
> mechanisms.
> 
> 
> C.3 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C.3>.
>
> 
Multiple interfaces
> 
> 
> 
> There are considerations for 2 or more IEEE 802.11-OCB interface 
> cards per vehicle.  For each vehicle taking part in road traffic,
> one IEEE 802.11-OCB interface card could be fully allocated for Non
> IP safety-critical communication.  Any other IEEE 802.11-OCB may be
> used for other type of traffic.
> 
> The mode of operation of these other wireless interfaces is not 
> clearly defined yet.  One possibility is to consider each card as an 
> independent network interface, with a specific MAC Address and a set 
> of IPv6 addresses.  Another possibility is to consider the set of 
> these wireless interfaces as a single network interface (not 
> including the IEEE 802.11-OCB interface used by Non IP safety 
> critical communications).  This will require specific logic to 
> ensure, for example, that packets meant for a vehicle in front are 
> actually sent by the radio in the front, or that multiple copies of 
> the same packet received by multiple interfaces are treated as a 
> single packet.  Treating each wireless interface as a separate 
> network interface pushes such issues to the application layer.
> 
> The privacy requirements of [] imply that if these multiple 
> interfaces are represented by many network interface, a single 
> renumbering event SHALL cause renumbering of all these interfaces. If
> one MAC changed and another stayed constant, external observers would
> be able to correlate old and new values, and the privacy benefits of
> randomization would be lost.
> 
> 
> 
> 
> Petrescu, et al. Expires February 18, 2018 [Page 31]
> 
> ------------------------------------------------------------------------
>
>  
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#page-32>
>
> 
Internet-Draft IPv6-over-80211ocb August 2017
> 
> 
> The privacy requirements of Non IP safety-critical communications 
> imply that if a change of pseudonyme occurs, renumbering of all
> other interfaces SHALL also occur.
> 
> 
> C.4 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-C.4>.
>
> 
MAC Address Generation
> 
> 
> 
> When designing the IPv6 over 802.11-OCB address mapping, we will 
> assume that the MAC Addresses will change during well defined 
> "renumbering events".  The 48 bits randomized MAC addresses will
> have the following characteristics:
> 
> o  Bit "Local/Global" set to "locally admninistered".
> 
> o  Bit "Unicast/Multicast" set to "Unicast".
> 
> o  46 remaining bits set to a random value, using a random number 
> generator that meets the requirements of [RFC4086
> <https://tools.ietf.org/html/rfc4086>].
> 
> The way to meet the randomization requirements is to retain 46 bits 
> from the output of a strong hash function, such as SHA256, taking as 
> input a 256 bit local secret, the "nominal" MAC Address of the 
> interface, and a representation of the date and time of the 
> renumbering event.
> 
> 
> Appendix D 
> <https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-04#appendix-D>.
>
> 
IEEE 802.11 Messages Transmitted in OCB mode
> 
> 
> 
> For information, at the time of writing, this is the list of IEEE 
> 802.11 messages that may be transmitted in OCB mode, i.e. when 
> dot11OCBActivated is true in a STA:
> 
> o  The STA may send management frames of subtype Action and, if the 
> STA maintains a TSF Timer, subtype Timing Advertisement;
> 
> o  The STA may send control frames, except those of subtype PS-Poll, 
> CF-End, and CF-End plus CFAck;
> 
> o  The STA may send data frames of subtype Data, Null, QoS Data, and 
> QoS Null.
> 
> Authors' Addresses
> 
> 
> 
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