[reSIProcate] Performance of a P2P-over-SIP program using resiprocate

[victor morales]

Hi!

I developed for my thesis a program that uses resip. The scheme works  
using super peers that answer queries from mobile users.

The super peer answers queries like this:

Client         reSIP super-peer
   |     INVITE      |
   |---------------->|
   |      606        |
   |<----------------|
   |      ACK        |
   |---------------->|
   |                 |

I am using 606 to carry the answer back to the client. In this basic  
form there is no P2P interaction (the P2P is between super-peers).

When using the "real" client all works perfectly fine.

Now I am doing some performance testing using SIPp (test tool).

The performance is not good, only 9CPS. After that the stack is  
re-sending 606 messages even though in a wireshark trace the ACK is  
sent immediately after the 606 is received by SIPp. Very soon the  
supe-peer drowns in retransmissions.

I recompiled the stack with a T1 timer value of 1000ms hoping that  
this would give more time to get the ACK processed, but got exactly  
the same results.

I have analyzed the logs in DEBUG and INFO modes, and cannot see any  
error message so I am assuming the ACK is not being dropped.

I know this is difficult to analyze like this but if someone could  
give me any pointers as why this could possibly be happening I would  
be extremely thankful.

Of course I have plenty of traces and logs, if you think those could  
be useful.

Thank you.

Victor M.