RE: Another requirement [Re: New (-02) version of IPv6 CPE Router draft is available for review]

["Wes Beebee (wbeebee)" <wbeebee@cisco.com>]

Agreed.  Perhaps a low precedence route (when all else but the default
route fails to match) that's a null route would be desirable..

- Wes 

-----Original Message-----
From: Francois-Xavier Le Bail [mailto:fx.lebail@yahoo.com] 
Sent: Thursday, July 31, 2008 11:12 AM
To: v6ops@ops.ietf.org; Wes Beebee (wbeebee)
Subject: RE: Another requirement [Re: New (-02) version of IPv6 CPE
Router draft is available for review]

--- On Thu, 7/31/08, Wes Beebee (wbeebee) <wbeebee@cisco.com> wrote:
> The route should go to the LAN ports (for the delegate prefix).  If 
> the LAN ports happen to not be up, doesn't this cause the packet to be

> > dropped?  If the destination matches a loopback, then the packets 
> can be serviced by the loopback.  If there is no LAN port (# of LAN 
> ports = 0), and if the device still does DHCPv6 PD (for other 
> addresses), then a null route may be appropriate as long as the other 
> addresses get serviced at a higher priority.

For example, if the delegated prefix is a /56 and the CPE use a /64
prefix for a subnet on a LAN Bridge and another /64 for a subnet on
another LAN interface outside the bridge, there are many prefix/subnet
not used.

Packet to theses unused prefix/subnet will loop without a discard or
unreachable route.

Francois-Xavier

> -----Original Message-----
> From: owner-v6ops@ops.ietf.org
> [mailto:owner-v6ops@ops.ietf.org] On
> Behalf Of Francois-Xavier Le Bail
> Sent: Thursday, July 31, 2008 10:17 AM
> To: v6ops@ops.ietf.org
> Subject: Another requirement [Re: New (-02) version of IPv6 CPE Router

> draft is available for review]
> 
> Another requirement:
> 
> The CPE should install a discard (null) or unreachable route for the 
> delegated prefix.
> 
> Without, a packet to an unused subnet (belonging to the delegated
> prefix) will loop between the CPE (default route to the Edge Router) 
> and the Edge Router (route for the delegated prefix to the CPE).
> 
> The only difference between the two options is: with unreachable route

> the CPE return ICMPv6 "Destination Unreachable/no route to 
> destination"
> message to the source address instead of only silently discard the 
> packet.
> 
> Francois-Xavier