IMO, there are two separate scenarios in which some sort of prefix 
delegation needs to be used:

1) A router establishes a point-to-point connection to a provider.
2) A new router is connected to a site's backbone link.

From Brian Haberman's comments at the interim meeting, it seemed that APD 
was designed for scenario (2), providing a means to "grow a network" (his 
words) without need for manual configuration.

However, scenario (1) seems much more common, and indeed was the origin of 
this thread.  Small IPv6 sites are inevitably connected to the 6bone with 
either a p-t-p tunnel or PPP, and there is no good reason we shouldn't 
have some kind of mechanism to autoconfigure the border routers at these 
sites.  A draft by Itojun (draft-itojun-ipv6-dialup-requirement-02.txt) 
describes some of the mechanisms that could be used for configuration, but 
makes no recommendations.

Instead of using a stateful protocol like DHCPv6 or APD to configure
customer sites, perhaps it would be best to use router advertisements on
the p-t-p link.  This was one of the more popular candidates for dialup
configuration during Itojun's presentation in Seattle (the other popular
candidate was APD).  Instead of overloading the Prefix Information option,
however, we could add an additional option to the router advertisement
messages, "Delegated Prefix".  This option could only be used on p-t-p
links, of course.

This technique would be lightweight, would be easy to implement for both
the ISP and client sides, and would provide all the functionality needed
for 90% of sites.  -Nathan

-- 
+-------------------+---------------------+------------------------+
| Nathan Lutchansky | [EMAIL PROTECTED] |  Lithium Technologies  |
+------------------------------------------------------------------+
|  I dread success.  To have succeeded is to have finished one's   |
|  business on earth...  I like a state of continual becoming,     |
|  with a goal in front and not behind. - George Bernard Shaw      |
+------------------------------------------------------------------+

Attachment: msg05069/pgp00000.pgp
Description: PGP signature

Reply via email to