User manual

Total Access 600 Series T1 ATM IAD UIG/64200681L2-31B

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2. VOICE OVER ATM OVERVIEW

Voice over ATM (VoATM) is the technology used to transmit voice conversations over a data network using Asyn-

chronous Transfer Mode (ATM). There are several potential benefits to moving voice over a data network using ATM.

First, the small, fixed-length cells require lower processing overhead. Second, these small, fixed-length cells allow

higher transmission speeds than traditional packet switching methods.

ATM allocates bandwidth on demand, making it suitable for high-speed connection of voice, data, and video services.

Conventional networks carry data in a synchronous manner. Because empty slots are circulating even when the link is

not needed, network capacity is wasted. ATM automatically adjusts the network capacity to meet the system needs.

3. VOICE OVER ATM APPLICATION

The echo canceller is used in ATM voice applications that require G.165 echo cancellation. The Total Access 600 also

contains an integrated ADPCM encoder/decoder for voice compression.

Figure 2 shows a typical VoATM application. The Total Access 600 connects to the ATM Network to provide both

voice and high speed data from a single platform.

Figure 2. Voice over ATM

Refer to the next section, Configuring the Total Access 600, for general configuration instructions.

Refer to the appendices at the end of this document for information on using the Total Access 600 in

specific applications:

• Appendix D. Voice Gateway Quick Start Procedure (Voice Turn up) on page 65.

• Appendix E. RFC1483 Quick Start (IP Routing) on page 67.

• Appendix F. RFC1483 Quick Start (IP Routing with NAT) on page 69.

• Appendix G. RFC1483 Quick Start (Bridging) on page 70.