Switching to VoIP

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Chapter 2: Voice over Data: Many Conversations, One Network

always be possible. Not all sites where you want to use IP phones have Ethernet wir-

ing in place.

If you had an old 10Base2 Ethernet segment at a certain site, you wouldn’t be able to

connect any IP phones at that site, because there are no IP phones on the market that

support the physical layer interfaces (BNC coax connectors) required by 10Base2

Ethernet. Moreover, 100BaseT is the only Ethernet spec that allows for the right

quality-of-service required to support a large rollout of IP phones.

Project 2.1. Configure an IP Hardphone

and the VoIP Test Network

To complete this project, an IP hardphone is needed. We’ll use the

Grandstream Budgetone 100 series phones in this example.

What you need for this project:

• Grandstream IP phone

• LAN

IP phones are really just software applications that speak VoIP’s protocols: SIP,

SCCP, H.323, or MGCP for call signaling; RTP for audio transmission; and some-

times LDAP for directory integration. They may also include XML or Java services so

that their displays and buttons can be used to further enhance the end user’s tele-

phony experience. When bundled together, this suite of protocol software that com-

prises an IP phone can run either on a PC, what we call a softphone, or on a

specialized ...