VoiceCon San Francisco, 2008

Terry Slattery
Principal Architect

I’m speaking at VoiceCon San Francisco 2008 on the topic of Troubleshooting in Converged Networks.  That’s a fancy title to say that I’ll be talking about VoIP troubleshooting.  There are three excellent speakers this time around: Steve Guthrie of CA, Mike Hollier of Psytechnics, and me.  The moderator is David Yedwab of Market Strategy and Analytics Partners.

I did a similar talk at Voicecon Spring 2008 in Orlando and the slides are posted on the Netcordia web site under Resources/Webinars.  I noticed that the last time I gave this talk, most of the audience was taking notes during my part of the presentation.  I focus on real things that you can monitor and do to determine that voip problems exist and how to address them in concrete ways.  That’s why people were taking notes.  Like them, I was tired of presentations that talked in such general terms that I couldn’t take any action items or ideas back to work with me.  So my presentation focuses on real symptoms and their causes and what you can do to address them.  Of course, there’s a limit to what I can cover in a 15-20 minutes (three speakers in an hour). I’m talking with the VoiceCon folks about doing an hour-long troubleshooting session where I can talk about problems in more detail and cover more types of problems.

A good example is echo and its causes.  An attendee at a past presentation came up to me after the session and asked more specific questions about the sources of echo.  Seems that he had an echo problem that had been bugging him for some time.  We discussed several potential sources of echo and how to go about trying to eliminiate it.

I later found another potential source of echo while talking with some of the folks at Chesapeake Netcraftsmen. There are some versions of DSPs that have buggy code and that generate echo on their own when you’re using a DSP to do transcoding or for a conference call.  The fix is new code for the DSP (assuming that the problem is rectified with new code and doesn’t need new hardware).

If you’re at VoiceCon, stop by and say hello or participate with your own description of the best VoIP troubleshooting problem you’ve encountered.



Re-posted with Permission 

NetCraftsmen would like to acknowledge Infoblox for their permission to re-post this article which originally appeared in the Applied Infrastructure blog under http://www.infoblox.com/en/communities/blogs.html


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Nick Kelly

Cybersecurity Engineer, Cisco

Nick has over 20 years of experience in Security Operations and Security Sales. He is an avid student of cybersecurity and regularly engages with the Infosec community at events like BSides, RVASec, Derbycon and more. The son of an FBI forensics director, Nick holds a B.S. in Criminal Justice and is one of Cisco’s Fire Jumper Elite members. When he’s not working, he writes cyberpunk and punches aliens on his Playstation.


Virgilio “BONG” dela Cruz Jr.

CCDP, CCNA V, CCNP, Cisco IPS Express Security for AM/EE
Field Solutions Architect, Tech Data

Virgilio “Bong” has sixteen years of professional experience in IT industry from academe, technical and customer support, pre-sales, post sales, project management, training and enablement. He has worked in Cisco Technical Assistance Center (TAC) as a member of the WAN and LAN Switching team. Bong now works for Tech Data as the Field Solutions Architect with a focus on Cisco Security and holds a few Cisco certifications including Fire Jumper Elite.


John Cavanaugh

CCIE #1066, CCDE #20070002, CCAr
Chief Technology Officer, Practice Lead Security Services, NetCraftsmen

John is our CTO and the practice lead for a talented team of consultants focused on designing and delivering scalable and secure infrastructure solutions to customers across multiple industry verticals and technologies. Previously he has held several positions including Executive Director/Chief Architect for Global Network Services at JPMorgan Chase. In that capacity, he led a team managing network architecture and services.  Prior to his role at JPMorgan Chase, John was a Distinguished Engineer at Cisco working across a number of verticals including Higher Education, Finance, Retail, Government, and Health Care.

He is an expert in working with groups to identify business needs, and align technology strategies to enable business strategies, building in agility and scalability to allow for future changes. John is experienced in the architecture and design of highly available, secure, network infrastructure and data centers, and has worked on projects worldwide. He has worked in both the business and regulatory environments for the design and deployment of complex IT infrastructures.