15 Jul
2005
15 Jul
'05
3:48 p.m.
On 15-07-2005 07:25, Dave wrote:
Hi,
I am trying to understand the section 5.1.1
(mediaproxy ser.cfg analysis) and I am having trouble
understanding RE-INVITES and loose-routing:
Consider following scenario:
UA1 - SER -- P2 - UA2
1) When SER gets a REINVITE from UA1, what happens?
How does SER know it is a REINVITE? Does it work as
follows: When SER gets a REINVITE, it checks it's
memory to see if an existing TransactionID exists and
if yes, then it know that this is a REINVITE?
re-INVITE messages have To tag. Normal INVITEs do not have To tag.
Even if it knows it is a REINVITE, what role does
loose_route() play?
re-INVITE messages are sent within an existing dialog and thus they
hit the proxy only if the proxy inserted Record-Route header field.
2) WHY does the line 85 on page 40 say
"n order to ensure that we are dealing only with an
actual re-INVITE, we must make sure
the has_totag() function returns TRUE and
loose_route() is also TRUE."
Why would the REINVITE have a to_tag()?
See above or RFC3261.
Why must the loose_route return TRUE for RE-INVITES?
Won't REINVITES be also record_routed() before
reaching the loose_route() directive?
ANy explanations will be appreciated.
Jan.