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More and more businesses today have their receive phone service through Internet instead of local phone company lines. Many businesses are also using their internal local and wide-area network infrastructure to replace legacy enterprise telephone networks. This migration to a single network carrying voice and data is called convergence, and it's revolutionizing the world of telecommunications by slashing costs and empowering users. The technology of families driving this convergence is called VoIP, or Voice over IP.

VoIP has advanced Internet-based telephony to a viable solution, piquing the interest of companies small and large. The primary reason for migrating to VoIP is cost, as it equalizes the costs of long distance calls, local calls, and e-mails to fractions of a penny per use. But the real enterprise turn-on is how VoIP empowers businesses to mold and customize telecom and datacom solutions using a single, cohesive networking platform. These business drivers are so compelling that legacy telephony is going the way of the dinosaur, yielding to Voice over IP as the dominant enterprise communications paradigm.

Developed from real-world experience by a senior developer, O'Reilly's Switching to VoIP provides solutions for the most common VoIP migration challenges. So if you're a network professional who is migrating from a traditional telephony system to a modern, feature-rich network, this book is a must-have. You'll discover the strengths and weaknesses of circuit-switched and packet-switched networks, how VoIP systems impact network infrastructure, as well as solutions for common challenges involved with IP voice migrations. Among the challenges discussed and projects presented:

  • building a softPBX

  • configuring IP phones

  • ensuring quality of service

  • scalability

  • standards-compliance

  • topological considerations

  • coordinating a complete system ?switchover?

  • migrating applications like voicemail and directory services

  • retro-interfacing to traditional telephony

  • supporting mobile users

  • security and survivability

  • dealing with the challenges of NAT

To help you grasp the core principles at work, Switching to VoIP uses a combination of strategy and hands-on "how-to" that introduce VoIP routers and media gateways, various makes of IP telephone equipment, legacy analog phones, IPTables and Linux firewalls, and the Asterisk open source PBX software by Digium. You'll learn how to build an IP-based or legacy-compatible phone system and voicemail system complete with e-mail integration while becoming familiar with VoIP protocols and devices. Switching to VoIP remains vendor-neutral and advocates standards, not brands. Some of the standards explored include:

  • SIP

  • H.323, SCCP, and IAX

  • Voice codecs

  • 802.3af

  • Type of Service, IP precedence, DiffServ, and RSVP

  • 802.1a/b/g WLAN

If VoIP has your attention, like so many others, then Switching to VoIP will help you build your own system, install it, and begin making calls. It's the only thing left between you and a modern telecom network.

Subscriber Reviews

Average Rating: 4.75 out of 5 rating Based on 4 Ratings

"Excellent book" - by wrondon on 08-NOV-2011
Reviewer Rating: 1 star rating2 star rating3 star rating4 star rating5 star rating
Good Ideas and great explanations. I highly reccomend it.
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"Best book for techies" - by jcg1541 on 22-APR-2010
Reviewer Rating: 1 star rating2 star rating3 star rating4 star rating5 star rating
I have only read 1/3 of the book and am progressing. I think Ted did an excellent job.

My only comment is that Ethernet's distance limitation is not due to copper attenuation. Ethernet's distance limitation is due to the packet size-design/speed of light. There are plenty of other protocols that run over copper over a much longer distance than Ethernet protocol.

In Ethernet 100, if you send 100Mbits per second and the packet head and tail has 1K bits in between, then there are 10K feet in between the packet head and tail. Every bit occupies 10 feet on the wire for the moment. It's like using a 55MPH-limit high way for a truck convoy business. The truck stops can not stratch too long for the head truck and tail truck to coordinate. A 75 MPH-limit high way allows longer distance in between truck stops. I think most people with an EE degree know this fact, though.

Most people with EE degree will agree that time is a very mysterious thing. It is related to light. Time is the hardest thing to engineer. Dr. Einstein spent his entire life deal with time/light entanglement.

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