Re: [dhcwg] Relay Agent Options.

Dear Achint,

I assume the "Relay Agent Options" in your question refers to the "Relay 
Agent Information Option" proposed in
<http://bgp.potaroo.net/ietf/idref/draft-droms-dhc-v6-relayopt/rfcmarkup?repository=/away/ietf&url=/away/ietf/all-ids/draft-droms-dhc-v6-relayopt-00.txt>draft-droms-dhc-v6-relayopt-00.txt

At 09:20 PM 12/2/2004, Achint Setia wrote:

>Hi,
>
>I have a couple of doubts regarding the Relay Agent Options:-
>
>1. What is the motive behind allowing the relay agent to add options
>while
>    forwarding the client packet to the server? Are they to be used by
>the
>    server in configuration selection for the client?

Yes, the info carried by the Relay Agent Information Options is intended be 
used by the server
as HINTs for assigning configuration parameters to the client based on 
local server policy.
Similar capability exists for DHCPv4 (See RFC3046 and 
<http://bgp.potaroo.net/ietf/idref/draft-droms-dhc-v6-relayopt/rfcmarkup?repository=/away/ietf&url=/away/ietf/all-ids/draft-ietf-dhc-agentopt>draft-ietf-dhc-agentopt-radius-08.txt
for example.).

The main motivation behind 
<http://bgp.potaroo.net/ietf/idref/draft-droms-dhc-v6-relayopt/rfcmarkup?repository=/away/ietf&url=/away/ietf/all-ids/draft-droms-dhc-v6-relayopt-00.txt>draft-droms-dhc-v6-relayopt-00.txt
is to use the proposed option to allow a NAS to relay some RADIUS 
attributes received
from the HAAA server to the DHCPv6 server so as to help the latter's
assignment. Please refer to the above RFC/drafts for existing applications 
of such option
in DHCPv4 environment.

>2. If yes, does that mean that when the server sends back the Relay
>Reply,
>    the ONLY TWO options that can be included are the Relay Message and
>the
>    interface id.

>    I am asking this because I am not sure as to how the relay agent will
>
>    handle options other than these two in the Relay Reply?
As proposed in 
<http://bgp.potaroo.net/ietf/idref/draft-droms-dhc-v6-relayopt/rfcmarkup?repository=/away/ietf&url=/away/ietf/all-ids/draft-droms-dhc-v6-relayopt-00.txt>draft-droms-dhc-v6-relayopt-00.txt, 

a dhcpv6 server supporting such option will echo the Option in its Relay 
reply, which will then
be stripped away by the relay agent before the reply is passed back to the 
client.
In other words, if the proposed option is used, the Relay Reply will 
include this new Relay Agent
Information Option similar to the way how the current dhcpv6 interface id 
option is included.
Lastly, based on feedbacks received from the Mailing list and during 
IETF61, the next revision
of the draft-droms-dhc-v6-relayopt-00.txt will be focusing on the
support of RADIUS attribute relay, instead of general relay info.
Please refer to the thread of discussion in 
http://www.ietf.org/mail-archive/web/dhcwg/current/msg04136.html
for more details.

Hope this helps.

Regards,

Wing

>Hope someone can clarify them.
>
>Thanks,
>Achint Setia.
>
>
>
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