Subject: [Dime] Diameter Message Maximum Length

From: Andrew Booth <[email-masked]>
Date: Fri, 8 Aug 2014 10:33:57 -0400

Hi,

I have a couple of questions about maximum message size in Diameter.

A Diameter message header has a 3 byte length indicator, so a maximum
message length of 16777215.  I don't see any way for Diameter node to
advertise support for a smaller message length.  Does that mean that a node
is expected to support a message length up to 0xffffff?  Or is it free to
impose its own upper limit and reject (send an error) if the message is too
long?

Meanwhile, in RFC6083 (DTLS/SCTP):
       However, the following limitations still apply:

       o  The maximum user message size is 2^14 bytes, which is the DTLS
           limit.

Am I reading this correctly that this limits Diameter message lengths to
2^14 when using DTLS/SCTP?  Or is there some kind of workaround to this
limitation?

Thanks for any info,
Andrew