September 2008
Intermediate to advanced
550 pages
18h 10m
English
Content preview from VoIP Voice and Fax Signal ProcessingBecome 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,
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.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.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.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.
2.2 TYPICAL VoIP DEPLOYMENT EXAMPLE
A typical deployment scenario for VoIP is shown in Fig. 2.3. In VoIP deployment, various voice-interfacing CPEs, soft switches, and VoIP–PSTN gateways are associated to establish the VoIP call. The main functions of various supporting infrastructure boxes are indicated in this section. For voice and data applications, CPEs communicate to the IP network through LAN or wide area network (WAN) interfaces. The LAN and WAN interfaces include Ethernet, a digital subscriber line (DSL), a very high-speed DSL (VDSL), a WLAN, a passive optical network (PON), dial-up, cable interfaces, USB, and more.
The software running on computers and add-on cards with voice interfaces can also function like the CPE and communicate with the Internet through LAN interfaces. VoIP adapters have simple voice and LAN data functions, whereas IAD or RG will have a direct WAN interface with many data-centric LAN interfaces. The IP phone is a single-user CPE terminal used to make a VoIP call. CPE terminals are also called end points.
Figure 2.3. Typical VoIP deployment functions.
VoIP–PSTN gateways establish the routing of calls to the existing PSTN network. These gateways are connected to the PSTN network through T1/E1/J1, ISDN, and FXO interfaces. Based on the signaling protocol used, the SIP server, the MGCP media gateway controller, or the H.323 gatekeeper establishes the ...
Become 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,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
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.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
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.