Re: draft-wbeebee-ipv6-cpe-router-04 comments

[james woodyatt <jhw@apple.com>]

On Mar 23, 2009, at 11:25, Hemant Singh (shemant) wrote:
> <hs-wb>
> Numbered or Unnumbered models aside, the CPE Rtr receives an RA from  
> the
> neighboring first hop SP router. CPE Rtr receives the RA and knows  
> this
> is the IPv6 default router.
> </hs-wb>

I don't see in the Unnumbered Model where the CPE is required to send  
any RS, nor do I think it's safe to assume that CPE routers will ever  
receive any unsolicited multicast RA announcements.

> -----
> Section 5.4 "Process RAs"
>
> Do these include RFC 4191 More Specific Route advertisements?  Yay!
> That will make the rogue RA problem a whole lot more fun.
>
>
> <hs-wb>
> This section clearly discusses only the direction where an RA comes to
> the CPE Rtr from the SP router to the home.  For a cable and DSL  
> network
> the SP to the cable modem or DSL modem link is cable RF transport or  
> DSL
> telco network.  Such networks are deemed very secure.  A Rogue RA is  
> not
> expected in this direction.

Be careful here.  RFC4191 MoreSpecificRoute messages, properly formed,  
are neither rogue nor accidental.

So.  Are CPE routers required to process RFC4191 MoreSpecificRoute  
options, or are they required to ignore them?  Or does this draft even  
want to take a position?



--
james woodyatt <jhw@apple.com>
member of technical staff, communications engineering