[SR-Users] To tags in 407 challenges

[Alex Balashov]

Hi,

This may be more a SIP question than a Kamailio question, but I am
trying to figure out why 407 challenges from Kamailio contain To tags. 

I suppose I've not run across it before, and I can't find an RFC-based
rationale. A negative reply to an invite transaction without an
intermediate early dialog-forming reply (e.g. 183 with To tag) does not
form a dialog, nor takes place within a context in which a dialog was
created. So what gives?

Insights appreciated!

-- Alex

-- 
Alex Balashov | Principal | Evariste Systems LLC

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