Re: [ipwave] rereview of draft-ietf-ipwave-ipv6-over-80211ocb-45

["Pascal Thubert (pthubert)" <[e-mail]>]

Hello Nabil



OLD:



In order to transmit IPv6 packets on IEEE 802.11 networks running

   outside the context of a basic service set (OCB, earlier "802.11p")

   there is a need to define a few parameters such as the supported

   Maximum Transmission Unit size on the 802.11-OCB link, the header

   format preceding the IPv6 header, the Type value within it, and

   others.  This document describes how IPv6 (including addressing and

   basic ND) can be used to communicate among nodes in range of one

   another over IEEE 802.11-OCB.  Optimizations and usage of IPv6 over

   more complex scenarios is not covered and is subject of future work.







NEW:





In order to transmit IPv6 packets on IEEE 802.11 networks

        running outside the context of a basic service set (OCB,

        earlier "802.11p") there is a need to define a few parameters

        such as the supported Maximum Transmission Unit size on the

        802.11-OCB link, the header format preceding the IPv6 header,

        the Type value within it, and others.  This document

        provides methods and settings, and describes limitations,

        for using IPv6 to communicate among nodes in range of one another

        over a single IEEE 802.11-OCB link with minimal change to existing stacks.

        Optimizations and usage of IPv6 over more complex scenarios

        is not covered and is subject of future work.





  *   Excellent







Introduction





OLD:



The IPv6 network layer operates on 802.11-OCB in the same manner as

   operating on Ethernet, but there are two kinds of exceptions:



   o  Exceptions due to different operation of IPv6 network layer on

      802.11 than on Ethernet.  To satisfy these exceptions, this

      document describes an Ethernet Adaptation Layer between Ethernet

      headers and 802.11 headers.  The Ethernet Adaptation Layer is

      described Section 4.2.1<https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-45#section-4.2.1>.  The operation of IP on Ethernet is

      described in [RFC1042<https://tools.ietf.org/html/rfc1042>], [RFC2464<https://tools.ietf.org/html/rfc2464>] .









NEW:



The IPv6 network layer operates on 802.11-OCB in the same manner as

   operating on Ethernet, but there are two kinds of exceptions:



   o  Exceptions due to different operation of IPv6 network layer on

      802.11 than on Ethernet. The operation of IP on Ethernet is

      described in [RFC1042<https://tools.ietf.org/html/rfc1042>], [RFC2464<https://tools.ietf.org/html/rfc2464>] .





  *   Works for me





3.  Communication Scenarios where IEEE 802.11-OCB Links are Used







OLD:



   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;







NEW:



The IEEE 802.11-OCB Networks are used for vehicular communications,

as 'Wireless Access in Vehicular Environments’. In particular, we refer the reader to [I-D.ietf-ipwave-vehicular-networking], that lists some scenarios and  requirements for IP in Intelligent Transportation Systems.



  *   Yes







OLD:



The link model is the following: STA --- 802.11-OCB --- STA.  In

   vehicular networks, STAs can be IP-RSUs and/or IP-OBUs.  While

   802.11-OCB is clearly specified, and the use of IPv6 over such link

   is not radically new, the operating environment (vehicular networks)

   brings in new perspectives.





NEW:





The link model is the following: STA --- 802.11-OCB --- STA.

          In vehicular networks, STAs can be IP-RSUs and/or IP-OBUs.

    All links are assumed to be P2P and multiple

    links can be on one radio interface. While 802.11-OCB is clearly  specified, and the use of IPv6 over such link is not radically new, the operating environment (vehicular networks) brings in new perspectives.



  *   OK . I’d rather replace “the use of IPv6 over such link is not radically new” with “a legacy IPv6 stack can operate on such links”





4<https://tools.ietf.org/html/draft-ietf-ipwave-ipv6-over-80211ocb-45#section-4>.  IPv6 over 802.11-OCB





OLD:





The default MTU for IP packets on 802.11-OCB MUST be 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 on the Internet must have a minimum MTU of 1280 octets.







NEW:





The default MTU for IP packets on 802.11-OCB is inherited

          from RFC2464 and is 1500 octets. This value

          of the MTU respects the recommendation that every link on

          the Internet must have a minimum MTU of 1280 octets (stated

          in <xref target="RFC8200"/>, and the recommendations

          therein, especially with respect to fragmentation).



> OK .







4.2.  Frame Format







OLD:



   IP packets MUST be transmitted over 802.11-OCB media as QoS Data

   frames whose format is specified in IEEE 802.11(TM) -2016

   [IEEE-802.11-2016].





NEW:



   IP packets MUST be transmitted over 802.11-OCB media as QoS Data

   frames whose format is specified in IEEE 802.11 spec.



Ø  Leave the reference just use a dateless one, e.g.:

Ø

      <reference anchor="IEEEstd80211">

         <front>

            <title>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

            </title>

            <author>

               <organization>

                      IEEE standard for Information Technology

  </organization>

            </author>

            <date/>

         </front>

      </reference>



OLD:



The IPv6 packet transmitted on 802.11-OCB MUST be immediately

preceded by a Logical Link Control (LLC) header and an 802.11 header.





NEW:



IPv6 packet transmitted on 802.11-OCB are immediately preceded

by a Logical Link Control (LLC) header and an 802.11 header





Ø    Good



OLD:



In the 802.11 header, the value of the

   Subtype sub-field in the Frame Control field MUST be set to 8 (i.e.

   'QoS Data'); the value of the Traffic Identifier (TID) sub-field of

   the QoS Control field of the 802.11 header MUST be set to binary 001

   (i.e.  User Priority 'Background', QoS Access Category 'AC_BK').



NEW:



 The mapping to the 802.11 data service MUST

 use a ‘priority’ value of 1, which specifies the use of QoS

 with a “Background” user priority.



Ø    I’ll trust you on that



OLD:



To simplify the Application Programming Interface (API) between the

   operating system and the 802.11-OCB media, device drivers MAY

   implement an Ethernet Adaptation Layer that translates Ethernet II

   frames to the 802.11 format and vice versa.  An Ethernet Adaptation

   Layer is described in



NEW:





To simplify the Application Programming Interface (API)

            between the operating system and the 802.11-OCB media,

            device drivers MAY implement IPv6 over Ethernet per RFC 2464

      and then a frame translation from 802.3 to 802.11 in order

      to  minimize the code changes.



Ø    Perfect



OLD:



4.4.  Stateless Autoconfiguration



   There are several types of IPv6 addresses [RFC4291], [RFC4193], that

   MAY be assigned to an 802.11-OCB interface.  This section describes

   the formation of Interface Identifiers for IPv6 addresses of type

   'Global' or 'Unique Local'.  For Interface Identifiers for IPv6

   address of type 'Link-Local' see Section 4.3.





NEW:



The steps a host takes in deciding how to

      autoconfigure its interfaces in IP version 6 are described in <xref

            target='RFC4862'/>. This section describes

            the formation of Interface Identifiers for IPv6 addresses of

            type 'Global' or 'Unique Local'.  For Interface Identifiers

            for IPv6 address of type 'Link-Local' see <xref

            target='ll'/>.



Ø    Works for me



OLD:



The Interface Identifier for an 802.11-OCB interface is formed using

   the same rules as the Interface Identifier for an Ethernet interface;





NEW:



The RECOMMENDED method for forming

          stable Interface Identifiers (IIDs) is described in <xref

          target='RFC8064'/>.  The method of forming IIDs described in

          section 4 of <xref target='RFC2464'/> MAY be used during

          transition time, in particular for IPv6 link-local

          addresses.





  *   Yes





OLD:



4.5.1.  Address Mapping -- Unicast



   The procedure for mapping IPv6 unicast addresses into Ethernet link-

   layer addresses is described in [RFC4861].





NEW:





4.5.1.  Address Mapping -- Unicast



   This draft is scoped for AR and DAD per RFC 4861.





  *   True





OLD:





4.5.2.  Address Mapping -- Multicast



<Snap>

                                             These issues may be

   exacerbated in OCB mode.  Solutions for these problems SHOULD

   consider the OCB mode of operation.





NEW:





These issues may be exacerbated in OCB mode.  Future improvement to this specification SHOULD consider solutions for these problems.



  *   Excellent





OLD:



The subnet structure on which the Neighbor Discovery

            protocol (ND) on OCB works ok is a single-link subnet; the

            status of ND operation on a subnet that covers multiple OCB

            links that repeat the signal at PHY layer, or the messages

            at MAC layer, is unknown.





NEW:





An IPv6 subnet on which Neighbor Discovery protocol (ND) can be used

can be mapped on an OCB network iff all nodes share a single broadcast

Domain, which is generally the case for P2P OCB links;

the status of ND operation on a subnet that covers multiple OCB links

That are not fully overlapping (NBMA) is not in scope.



  *   Yes. Maybe:

”

An IPv6 subnet on which Neighbor Discovery protocol (ND) can be used

can be mapped on an OCB network iff all nodes share a single broadcast

Domain, which is  generally the case for P2P OCB links (OCB is usually reflexive) but not for multipoint (OCB is generally not transitive);

the status of ND operation on a subnet that covers multiple OCB links

That are not fully overlapping (NBMA) is not in scope.

“





OLD:

The baseline Neighbor Discovery protocol (ND) [RFC4861<https://tools.ietf.org/html/rfc4861>] MUST be used over 802.11-OCB links.



NEW:

The baseline Neighbor Discovery protocol (ND) [RFC4861] MUST be supported over 802.11-OCB links.



Ø    Yes



 OLD:



Transmitting ND packets may prove to have

   some performance issues.  These issues may be exacerbated in OCB

   mode.  Solutions for these problems SHOULD consider the OCB mode of

   operation.  The best of current knowledge indicates the kinds of

   issues that may arise with ND in OCB mode; they are described in

   Appendix J.



NEW:



Transmitting ND packets may prove to have some performance issues.  These issues may be exacerbated in OCB

   mode.  Future solutions to OCB should consider solutions for avoiding broadcast.  The best of current knowledge indicates the kinds of issues that may arise with ND in OCB mode; they are described in Appendix J.







Ø    Yes







OLD:



Within the IPsec Security Architecture [RFC4301], the IPsec AH and

   ESP headers [RFC4302] and [RFC4303] respectively, its multicast

   extensions [RFC5374], HTTPS [RFC2818] and SeND [RFC3971] protocols

   can be used to protect communications.  Further, the assistance of

   proper Public Key Infrastructure (PKI) protocols [RFC4210] is

   necessary to establish credentials.  $



NEW:



Removed







Ø    OK





All the best,

Pascal