Re: New Technical Issues RE: WG last call in progress on VLAN/Priority Draft

[Barney Wolff <barney@databus.com>]

On Thu, Mar 16, 2006 at 12:27:18PM -0800, Glen Zorn (gwz) wrote:
> 
> I have given my reasoning several times, but I will repeat myself
> again: the Diameter AVP structure was designed with the fact in
> mind that Diameter messages are virtually unlimited in length.  For
> this reason, the header could be as big as desired, with little
> concern for overhead.  RADIUS messages, however, are strictly
> constrained in length and I've not seen any realistic scheme for
> expanding them in a backwards-compatible fashion.  Attribute overhead
> _is_ an issue in RADIUS; every octet taken for an AVP header is one
> less available for actual data.  Although the use of a Diameter
> header would allow for larger attributes, the increase in overhead
> means that there is actually less space available for attributes.

I would have thought that 4096 was quite generous, but I lack recent
operational experience.  So I appeal to the group:  What's the largest
RADIUS message that's been seen in the wild?  Are we anywhere close
to being constrained by the 4096 limit, which we agree cannot be changed?

I would also point out that we are not suggesting that all future RADIUS
attributes use the Diameter format.  Only those that need more than 253
bytes, use a Diameter data type (including Grouped), or have type number
greater than 255 would need to do so.

Regards,
Barney

--
to unsubscribe send a message to radiusext-request@ops.ietf.org with
the word 'unsubscribe' in a single line as the message text body.
archive: <http://psg.com/lists/radiusext/>