Dealing with a heap of SIP logs to pin point a certain call might sometimes be a difficult journey. Interesting tools such as sipworkbench or sipx viewer already expose some functionalities to extract and analyse call logs.
However, our requirements were a bit different. We needed a tool able to parse text formatted sip logs on a platform with dozen of *NIX servers. The SIP applications are themself responsible to output formatted logs; we did not want to run infinite tcpdump for each application port on each server. Moreover, we leaned toward a command line tool that we can operate direcly on the servers without windowing requirements. Sip Viewer aims to output the extracted call flows as simple ASCII ladders directly in the command prompt (or using an eclipse plugin).
Finally, an important feature was to control the parser to not only aggregate according the the call-id header, but to extend our application logic in order to correlate many dialogs linked by a Back to Back User agent.