Re: [dhcwg] Link Address filed in Relay Messages

On Thu, Mar 15, 2007 at 11:02:59AM +0530, punit shah wrote:
> The RFC says Relay Agent must fill the RElay-Forward messages with a
> global/site local(now deprecated) address belonging to the same
> link as that of the user who needs to be allocated IPv6 address. But the
> problem is our sware has no means of knowing which link (or even MAC
> address) of the
> user and IPv6 addresses on the users link.
> 
> Is it possible to solve this problem in a rfc compliant manner and how?

I do not think so.

The MAC address is unimportant to a DHCPv6 server.  So long as the
DUID and IAID combine together to form one unique binding for one
unique client, the mechanics of those identifiers are irrelevant.

Not knowing at least one global address that resides on the link
the client is connected to is a big problem.

> Also would link local address be acceptable or alternatively a fictitious
> global address not neccesarily on the usre's l;ink?

I do not think so.

I think the best you can do is fill the link address field with
zeroes and hope for the best, but this requires some very strange
DHCPv6 server configuration - where the server is expected to
know where all clients are singly attached (this is very odd for
a DHCP server...the expectation is always that they move between
networks), and can give such addresses despite lack of hints from
the relay agents.

-- 
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