On Thursday 21 September 2006 23:12, Hume Vance wrote:

Hume,

> In other words, is it safe to restrict a Route to 128 bytes, for example? 

Absolutely not!  For the example you gave of a Route header, a number of 
implementations use the user part of the route URI for storing state between 
in-dialog requests, and as such can have very large user parts within the 
URI.  Never assume any limits at all about any field value's (or component 
of) maximum length, number of parameters, headers, etc, as it's just asking 
for problems.

> If not, what do implementations generally support?

I would hope all implementations striving for interoperability would not place 
a maximum upper limit on number of fields, a single field value, or any 
components of it - and instead, as others have suggested, allocate a 
scratchpad or allocate on a per field/value/component basis as it is parsed.

however, *if* you ever were to limit any message components's size for 
whatever reason, or the total size of all field values is too large due to 
hardware/cpu constraints, then ensure you reject/drop the message rather than 
just truncate a particular field.

on this note, the same would apply to fields that have an numerical value 
where they overflow - don't wrap them, reject/drop them!

 ~ Theo

-- 
Theo P. Zourzouvillys
http://www.crazygreek.co.uk
[EMAIL PROTECTED]
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