Many thanks for the direction. Have I read the Wireshark docs right in that it can reconstruct the audio of VoIP call from the packets captured?
I will firstly attempt to run simultaneous captures at both ends, inserting a 100Mbit hub between the router and PBX switch with PC's running Wireshark connected to the hub (can't afford a network probe). This will hopefully capture all traffic passing to the router including that destined to be sent across the VPN without causing to much of a skew to the data (due to the non duplex nature of the hub). If I can then reconstruct the audio I might have a better understanding of what the user is experiencing. I will try an repeat the exercise with a software based VoIP product that can be run from the two capture PC's assuming they will be up to the task (any suggestions?), or other VoIP hardware that can be used to connect direct without the need for the PBX. I hope this will at least give an indication of where the fault lies. However, I am beginning to suspect the PBX switches. We ran a simple test by disconnecting the rest of the data networks which made little/no difference. We are well within our bandwidth budgetary constraints (150 kbps) and the ISP latency between sites is only 45ms. If Wireshark isn't really the tool to get accurate quality scores, has anyone got any suggestions for a tool that might be better suited to the task - without breaking the bank? Thanks, Chris -----Original Message----- From: Jaap Keuter [mailto:[EMAIL PROTECTED] Sent: 28 September 2006 07:08 To: Community support list for Wireshark Subject: Re: [Wireshark-users] VoIP analysis and assessment Hi, [CLIP elaborate description] I think Wireshark is of limited use here. Things like MOS determination is not in it's realm. But it can be helpfull. I would go for test calls. Get down to the ends where the "buzz" problem is happening and from there call into an autoanswering upstream extension connected to a tone source. Capture the RTP traffic with Wireshark once determined that the "buzz" occurs. Save the payload of this capture and see what's made of it. If the buzzing is in there, you've got issues with the PSTN/VoIP codecs, if it's not the jitterbuffer in the terminals may be wacky. Just my E0.02 Jaap _______________________________________________ Wireshark-users mailing list Wireshark-users@wireshark.org http://www.wireshark.org/mailman/listinfo/wireshark-users