Switching to VoIP

This is the Title of the Book, eMatter Edition

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Chapter 11

CHAPTER 11

Troubleshooting Tools

The word troubleshooting may trigger memories of desperation when a critical sys-

tem was down and you couldn’t figure out why. Troubleshooting often justifies high-

priced consultants. The mere mention of it can make fainthearted IT executives

squirm… because if you’re troubleshooting, that means something’s wrong. Regard-

less, troubleshooting tools are an important ingredient in the VoIP success recipe.

If you’re building your standards-based VoIP network from the ground up today,

then you’re probably using SIP and not H.323. SIP is clearly the prevailing standard

for VoIP call signaling, as it provides more interoperability and easier troubleshoot-

ing. The tools used to troubleshoot SIP and H.323 are largely the same, though:

packet sniffers, log analysis, and softphones.

Since SIP is a framework for real-time media applications, the stability of one SIP-

based system to the next can vary greatly. Problems are most likely at the applica-

tion layer. Troubleshooting them may require a specific knowledge of the applica-

tion, or even access to its source code. This isn’t always practical or available. Many

system engineers aren’t hard-core C programmers. Of course, for those who want to

probe the mechanics of IP telephony with C, a great ...