Subject: RE: [AAA-WG]: [issue] AAA URI is Overloaded

From: Jacques Caron <[email-masked]>
Date: Wed, 27 Feb 2002 23:15:59 +0100

At 20:44 27/02/2002, [email-masked] wrote:
>   The DiameterIdentity format is derived from the OctetString AVP Base 
> Format.
>   It uses the UTF-8 encoding and has the same requirements as the 
> UTF8String.
>   In addition, it must follow the Uniform Resource Identifiers (URI) syntax
>   [URI] rules specified below:

What is the URI stuff doing here? It's not a URI, just a FQDN all by 
itself. If you need the reference to [URI] just for the definition of 
"fqdn" I think it's really ambiguous.

>         DiameterIdentity  = fqdn
>
>   A Diameter node must be uniquely identified by its DiameterIdentity, which
>   is an FQDN.  If multiple Diameter nodes run on the same host, each 
> Diameter
>   node MUST be assigned a unique DiameterIdentity.

Also one thing I forgot to point out earlier: it would be good to state 
that the DiameterIdentity must be constant for the process, whatever the 
interface it is used on. Something like:

"If a Diameter node can be identified by several FQDNs, one single FQDN 
should be picked at startup, and used as the only DiameterIdentity for that 
node, whatever the connection it is sent on."

It might not be a bad idea to add a sentence to explain what it's used for, 
such as:
"The DiameterIdentity value is used to uniquely identify a Diameter node 
for purposes of duplicate connection and routing loop detection".

Additionally, some text all along the draft needs to be modified to 
reference the right AVP type (DiameterURI vs DiameterIdentity) depending on 
the context, of course.

Jacques.

_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com

---

From: David Spence <[email-masked]>
Date: Wed, 27 Feb 2002 19:08:43 -0500

Jacques Caron wrote:
>... 
>... 

You know, I had thought that all AVPs were of type DiameterIdentity with the
Diameter URI only used in config files and other resource location
protocols.  But now that I think about it, the Redirect-Host AVP is an
exception.  The recipient of an answer message containing a Redirect-Host
AVP is expected to form a peer-to-peer connection with the redirect host. 
So the full URI information is needed.  Therefore we really *do* need to
define two different AVP types -- DiameterURI and DiameterIdentity.  The
Redirect-Host AVP is of type DiameterURI.  Are all the other AVPs of type
DiameterIdentity?

---

From: Jacques Caron <[email-masked]>
Date: Thu, 28 Feb 2002 01:51:15 +0100

Right. Anything that "points to" a Diameter node is an URI. Anything that 
identifies a node is Identity.

Redirect-Host should be an URI, and actually be renamed Redirect-URI for 
consistency.

Route-Record, Origin-Host, Destination-Host and Proxy-Host should be 
identities.

Apparently Alternate-Host and Source-Route are no longer with us, but if 
they come back, the first one is an URI and the second an Identity.

Jacques.