Klaus Darilion writes:
They achieve both the same. I don't remember the
problems anymore which
caused add_contact_alias() to be implemented. IIRC I think it was that
some clients did not put "transport=tcp" into the Contact header and
thus the fix_anted_contact missed the transport - add_contact_alias
always adds the transport protocol. But that is just a guess, I may be
wrong.
the main reason why i implemented those two functions was to assure that
request uri in in-dialog requests is always correct. regarding tcp
connection reuse, i don't remember why i wrote about that in the
tutorial. perhaps i was just mislead by the name of fix_nated_contact()
function that is incorrect. i just checked and the function has nothing
to do with nated contacts.
-- juha