July 2002
Intermediate to advanced
528 pages
15h 13m
English
Content preview from Practical VoIP Using VOCALBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Source Code
The code is large, among the largest of all the components within VOCAL. It is approximately 10 times larger than the MGCP translator, including the MGCP stack. A lot of the size has to do with having a large number of templates, each with its own debugging information. The translator starts as a 15MB process that grows as more calls are processed.
The translator is one of the more complicated components of VOCAL because there are two stacks, a large number of H.323 state machines, a translation state machine, an H.323 translator, and the SIP stack. We tried to write the translator and the gatekeeper so that it could be reused and understandable, and it appears that we were successful. The gatekeeper and router are modular and could be reused for other H.323 projects. The translator and proxy are specific implementations and cannot be reused.
Project Components
As we started planning our project, it occurred to us that the translator could be divided into several subprojects.
- Transport
We decided to use a certain type of transport, asynchronous I/O, with the potential to poll a large number of sockets. That approach was completely different from any of the code that was in VOCAL’s base. We essentially had to write a different type of socket infrastructure.
- SIP Proxy
This piece uses the VOCAL base proxy code.
- Gatekeeper
This portion of the code does the registration translation.
- H.323 router state machines
The call-signaling framework includes all of the H.323 state machines, ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.