Re: [MBONED] Adam Roach's No Objection on draft-ietf-mboned-driad-amt-discovery-10: (with COMMENT)

["Holland, Jake" <[e-mail]>]

Thanks Adam, the revised one looks good.  Your dedication to the
universal deployment of IPv6 is very inspiring.

Although I do think it ends up slightly less readable than the IPv4
version, I agree it's a reasonable tradeoff that helps to make IPv6
more natural to use when there's a choice, in alignment with the IAB
recommendation.  So I'll pull in your edit and make the text changes
to match the updated example.

However, I think I have to make a few changes to the addresses:
- For the multicast group I'll use ff3e::8000:d, to be a globally scoped
  address from the SSM space for dynamic allocation by a host (from
  Section 1 of RFC 4607 and Section 2.7 of RFC 2373)
- I'll make the sender the shorter address, so it fits into the diagram
  along with the larger group address I needed.  (The column count hits
  exactly on the limit...)


<revised-text>
                  +---------------+
                  |    Sender     |
   |    |         |  2001:db8::a  |
   |    |         +---------------+
   |Data|                 |
   |Flow|      Multicast  |
  \|    |/      Network   |
   \    /                 |        5: Propagate RPF for Join(S,G)
    \  /          +---------------+
     \/           |   AMT Relay   |
                  | 2001:db8:c::f |
                  +---------------+
                          |        4: Gateway connects to Relay,
                                      sends Join(S,G) over tunnel
                          |
                 Unicast           3: --> DNS Query: type=AMTRELAY,
                  Tunnel  |       /       a.0.0.0.0.0.0.0.0.0.0.0.
                                 /        0.0.0.0.0.0.0.0.0.0.0.0.
      ^                   |     /         8.b.d.0.1.0.0.2.ip6.arpa
      |                        /
      |                   |   /       <-- Response:
  Join/Leave       +-------------+         AMTRELAY=2001:db8:c::f
   Signals         | AMT gateway |
      |            +-------------+
      |                   |        2: Propagate RPF for Join(S,G)
      |        Multicast  |
                Network   |
                          |        1: Join(S=2001:db8::a,G=ff3e::8000:d)
                   +-------------+
                   |   Receiver  |
                   |  (end user) |
                   +-------------+

                         Figure 2: DRIAD Messaging

   In this simple example, the sender IP is 2001:db8::a, it is sending
   traffic to the group address ff3e::8000:d, and the relay IP is
   2001:db8::c:f.

   The content provider has previously configured the DNS zone that
   contains the reverse IP domain name for the sender's IP address so
   that it provides an AMTRELAY RR with the relay's IP address.  (See
   Section 4.3 for details about the AMTRELAY RR format and semantics.)
   As described in Section 2.5 of [RFC3596], the reverse IP FQDN of the
   sender's address "2001:db8::a" is:

   a.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.
                                                                  arpa.

   The sequence of events depicted in Figure 2 is as follows:

   1.  The end user starts the app, which issues a join to the (S,G):
       (2001:db8::a, ff3e::8000:d).

   2.  The join propagates with RPF through the receiver's multicast-
       enabled network with PIM [RFC7761] or another multicast routing
       mechanism, until the AMT gateway receives a signal to join the
       (S,G).

   3.  The AMT gateway performs a reverse DNS lookup for the AMTRELAY
       RRType, by sending an AMTRELAY RRType query for the reverse IP
       domain name for the sender's source IP address (the S from the
       (S,G)).

       The DNS resolver for the AMT gateway uses ordinary DNS recursive
       resolution until it has the authoritative result that the content
       provider configured, which informs the AMT gateway that the relay
       address is 2001:db8::c:f.

   4.  The AMT gateway performs AMT handshakes with the AMT relay as
       described in Section 4 of [RFC7450], then forwards a Membership
       report to the relay indicating subscription to the (S,G).

   5.  The relay propagates the join through its network toward the
       sender, then forwards the appropriate AMT-encapsulated traffic to
       the gateway, which decapsulates and forwards it as native
       multicast through its downstream network to the end user.

   In the case of an IPv4 (S,G), the only difference in the AMT relay
   discovery process is the use of the in-addr.arpa reverse IP domain
   name, as described in Section 3.5 of [RFC1035], instead of the
   in6.arpa domain name.  For example, if the (S,G) is (198.51.100.12,
   232.252.0.2), the reverse IP FQDN for the AMTRELAY query would be
   "12.100.51.198.in-addr.arpa.". 
</revised-text>

Thanks,
Jake


On 2019-12-19, 07:45, "Adam Roach" <[e-mail]> wrote:

I just now noticed that something on the mail handling path mangled my 
diagram pretty badly. What I tried to send looks like this:

https://www.dropbox.com/s/4l5orheo0fyv64s/driad-diagram.txt?dl=0

/a