Theodore Wallingford - "Switching to VoIP"

Posted By: Alexpal


Theodore Wallingford, "Switching to VoIP"
O'Reilly | ISBN 0596008686 | June 30, 2005 Year | CHM | 3,7 Mb | 502 Pages


More and more businesses today have their receive phone servicethrough Internet instead of local phone company lines. Manybusinesses are also using their internal local and wide-areanetwork infrastructure to replace legacy enterprise telephonenetworks. This migration to a single network carrying voice anddata is called convergence, and it's revolutionizing the world oftelecommunications by slashing costs and empowering users. Thetechnology of families driving this convergence is called VoIP, orVoice over IP.

VoIP has advanced Internet-based telephony a viable solution,piquing the interest of companies small and large. The primaryreason for migrating to VoIP is cost, as it equalizes the costs oflong distance calls, local calls, and e-mails to fractions of apenny per use. But the real enterprise turn-on is how VoIP empowersbusinesses to mold and customize telecom and datacom solutionsusing a single, cohesive networking platform. These businessdrivers are so compelling that legacy telephony is going the way ofthe dinosaur, yielding to Voice over IP as the dominant enterprisecommunications paradigm.

Developed from real-world experience by a senior developer,O'Reilly's Switching to VoIP provides solutions for the mostcommon VoIP migration challenges. So if you're a networkprofessional who is migrating from a traditional telephony systemto a modern, feature-rich network, this book is a must-have. You'lldiscover the strengths and weaknesses of circuit-switched andpacket-switched networks, how VoIP systems impact networkinfrastructure, as well as solutions for common challenges involvedwith IP voice migrations. Among the challenges discussed andprojects 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 directoryservices
— 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 toVoIP uses a combination of strategy and hands-on "how-to" thatintroduce VoIP routers and media gateways, various makes of IPtelephone equipment, legacy analog phones, IPTables and Linuxfirewalls, and the Asterisk open source PBX software by Digium.You'll learn how to build an IP-based or legacy-compatible phonesystem and voicemail system complete with e-mail integration whilebecoming familiar with VoIP protocols and devices. Switching toVoIP remains vendor-neutral and advocates standards, notbrands. 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 Switchingto VoIP will help you build your own system, install it, and beginmaking calls. It's the only thing left between you and a moderntelecom network.