Brian Sierakowski Posted August 10, 2009 Share Posted August 10, 2009 All, My company has been running into some issues, we install phone systems into businesses, and increasingly people are opting for the IP solutions. The trouble this causes us is now we not only have to troubleshoot the phone system, phones, programing, etc, but now we have to worry about latency, port blocking, routing, etc. I'm just curious if anyone knows of any tools or techniques we can use to test their infrastructure to drill down and see what exactly is causing the problems we're experiencing. Also, any resources or certifications I can use would be greatly appreciated. Thanks! -Brian Quote Link to comment Share on other sites More sharing options...
digip Posted August 10, 2009 Share Posted August 10, 2009 All, My company has been running into some issues, we install phone systems into businesses, and increasingly people are opting for the IP solutions. The trouble this causes us is now we not only have to troubleshoot the phone system, phones, programing, etc, but now we have to worry about latency, port blocking, routing, etc. I'm just curious if anyone knows of any tools or techniques we can use to test their infrastructure to drill down and see what exactly is causing the problems we're experiencing. Also, any resources or certifications I can use would be greatly appreciated. Thanks! -Brian I have yet to work on any of this, but we discussed it in class, and its one of the things I want to learn about myself. Cisco CCNA-Voice cert would get you what you want to know about this stuff. Im still working on my CCNA, but I want to take the Voice class because damn near every job today wants someone with voice experience. Using a switch, you can set up a voice vlan, so the traffic could be isolated for voice anyway, but voice does use quality of service control over other nodes on the same vlan and trunks. It takes priority and also uses UDP for its transport method, meaning, best of effort, connectionless transmission, it sends it down the wire and does no error checking or retransmitting of data. Reason being, its like listening to a radio braodcast, where when the reception gets static and cuts out, its because its missing part of the transmission, the radio station can't resend you what you lost, it just broadcasts, or multi casts the signal to everyone. Anything that hinders that transmission causes loss of data, or in this case, sound of the person at the other end. You wouldn't use TCP for this, as that would add more overhead to the traffic on the network in order to try and retransmit missing data, which would cause even more choppy phone calls and time waiting for the proper reconstructed messages, waiting for all the data to be sent at one time. UDP just streams it to the end point, and doesn't care if you received it or not. Quote Link to comment Share on other sites More sharing options...
Brian Sierakowski Posted August 10, 2009 Author Share Posted August 10, 2009 CCNA Voice is a great call, I think my vendor specific training will help a lot too, but I'm going to recommend this one as well. Any other suggestions would be great, especially if anyone knows any tools you can slap on their network to test for voice readiness. If none exist... that would be a very lucrative product. Drop the app on the network, run a scan, and get a report of how many VOIP conversations can take place simotaneously, detect traffic, raise flags such as blocked ports and other troubleshooting tips, etc. Just a thought :). Quote Link to comment Share on other sites More sharing options...
operat0r_001 Posted August 13, 2009 Share Posted August 13, 2009 cain and able has voice support. I got portable metasploit and w3af on my site :P google ntop and netflowd or just pop on the eternal firewall and TCPDUMP ftw :) Quote Link to comment Share on other sites More sharing options...
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