RE: Some Comments on ID/Loc Separation Proposals

[<Margaret.Wasserman@nokia.com>]

> An interface ID makes no sense to me.
> 
> The concept of a stack name, where there can be one or more "stacks"
> on a given host, provides the right granularity to me.
> Each "stack" can presumbly have one or more network interfaces.

I'm not suggesting that the AID in NOID should become an interface
ID.

Current discussion focuses on the use of an IP address as a node
identifier and as a locator.  And, I agree that it serves these 
two purposes.  

An IP address can be used, for example, to allow ULPs to indicate 
which physical interface to use for outbound packets by explictly 
choosing a source address.  This can be useful for multicast traffic 
and specialized ULPs such as routing protocols. 

The interface ID aspect of IP addresses can also be used to communicate
between ULPs and LLPs (lower layer protocols).  The ULPs may make
a specific source address selection to specify a virtual interface
that will be used to send outbound packets.  This can allow some
traffic to be sent through tunnels, or for per-application selection
between multiple paths that may have different properties (cost,
latency, bandwidth, etc.).

The use of IP addresses as interface identifiers may or may not
have any implications for NOID, as it seems that NOID will allow
ULP access to the real local IP addresses (??) -- the document
doesn't specifically say this, but I'm assuming that is how SCTP
would run over NOID, for example. This is a larger potential issue 
for other proposals, such as HIP.

Margaret