Re: New draft on embedding the RP address in IPv6 multicast address

[Pekka Savola <pekkas@netcore.fi>]

On Thu, 10 Oct 2002, Marshall Eubanks wrote:
> On Thu, 10 Oct 2002 14:21:44 +0300 (EEST)
>  Pekka Savola <pekkas@netcore.fi> wrote:
> > Hello,
> > 
> 
> Dear Pekka;
> 
>    A quick question about Section 4 :
> 
>   o "plen" MUST NOT be 0 (ie. not SSM)
> 
>      o "plen" MUST NOT be greater than 96
> 
>    The address of the RP can be obtained from a multicast address by
>    taking the following steps:
> 
>       1. take the last 96 bits of the multicast address
> 
>       2. zero the last 128-"plen" bits, and
> 
>       3. replace the last 4 bits with the contents of "RPad".
> 
> 
> If "plen" is = 1 (say), which seems to be allowed, then how do
> I zero the last 127 bits of a 96 bit slice of a multicast address ?
> 
> I am pretty sure this is not what you mean, but this is what I read it to say.

The first bullet makes it implicit that those 96 bits are placed at the 
beginning of a 128-bit address struct (which is assumed to have been 
initialized to zero).

But that should be clarified so there will be no misunderstandings, 
thanks.

 
> Regards
> Marshall Eubanks
> 
> 
> > Me and Brian Haberman have submitted a new draft to
> > internet-drafts@ietf.org. In the interim, it's available at:
> > 
> > http://www.netcore.fi/pekkas/ietf/draft-savola-mboned-mcast-rpaddr-00.txt
> > 
> >          "Embedding the Address of RP in IPv6 Multicast Address"
> > 
> > Abstract                                               
> > 
> >    As has been noticed, there is exists a huge deployment problem with
> >    global, interdomain IPv6 multicast: PIM RPs have no way of         
> >    communicating the information about multicast sources to other
> >    multicast domains, as there is no MSDP, and the whole interdomain Any
> >    Source Multicast model is rendered unusable; SSM avoids these        
> >    problems.  This memo outlines a way to embed the address of the RP in
> >    the multicast address, solving the interdomain multicast problem. The
> >    problem is three-fold: specify an address format, adjust the         
> >    operational procedures and configuration if necessary, and modify
> >    receiver-side PIM implementations.  In consequence, there would be no
> >    need for interdomain MSDP.             
> > 
> > It's 9 pages.
> > 
> > Comments are welcome, either directly or to the list(s) if appropriate.
> > 
> > -- 
> > Pekka Savola                 "Tell me of difficulties surmounted,
> > Netcore Oy                   not those you stumble over and fall"
> > Systems. Networks. Security.  -- Robert Jordan: A Crown of Swords
> > 
> > 
> > 
> > 
> > 
> > 
> 

-- 
Pekka Savola                 "Tell me of difficulties surmounted,
Netcore Oy                   not those you stumble over and fall"
Systems. Networks. Security.  -- Robert Jordan: A Crown of Swords