Re: [dhcwg] I-D Action: draft-ietf-dhc-dhcpv6-client-link-layer-addr-opt-00.txt

[Ted Lemon <[e-mail]>]

On Jul 11, 2012, at 5:10 PM, A. Gregory Rabil wrote:
> Okay, consider prefix-delegation, for example.  The requesting router will send an IA_PD request out the WAN interface to get a prefix which is then allocated to the downstream/LAN interface.  Since the packet is sent via the WAN interface, I believe that the relay would insert the link-layer address of the WAN interface in the request, and thus the prefix would then be "associated" with the WAN interface, whereas it is really associated with the LAN interface.  So, this is how the interface being configured is NOT the interface on which the packet is sent.  Further, consider a requesting router with two distinct downstream/LAN interfaces.  The PD requests for both LAN interfaces would be sent via the WAN interface, and thus the WAN's link-layer address will be inserted into the option by the relay (or learnt by the server from layer 2).  An administrator may wish to configure different prefixes and/or options for each LAN interface, but has no way to do identify them individually via the proposed mechanism.

So you're saying that we need the functionality because of a protocol feature that doesn't exist.   Got it.