Re: Flow label - the problem

[Erik Nordmark <erik.nordmark@sun.com>]

Iljitsch van Beijnum wrote:

> No, this id would be looked at when selecting the flow label for a  new 
> session. I.e.: when selecting a new flow label, the host would  see if 
> the flow label overlaps with one currently used, and then:
>
> - overlaps with known non-shim session: allow if dest addr is different
> - overlaps with known shim session: allow if shim id is different
> - overlaps with session of unknown type: don't allow
>
> There are probably other places wher ethe shim id would be useful too.

I don't understand how and when the initiator would discover this id.

The flow label should presumably be allocated before the initiator sends 
the first packet, but at that point in time all the shim knows is one 
ULID=locator (perhaps the application knows more, such as a FQDN and 
multiple ULIDs that it got from the DNS, but I don't think we can should 
 assume this).

Unless we always require a context establishment before sending the 
first ULP packet, you'd have to pick some "unique enough" flow label 
without knowing this id.

So I don't see how the ID helps.

   Erik