ZyXEL Communications 2602HW Series User Manual

Prestige 2602HW Series User’s Guide

Chapter 1 Getting To Know Your Prestige

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The Prestige allows you to simultaneously use multiple voice (SIP) accounts and assign them 
to one or both telephone ports.

The Prestige can simultaneously handle multiple voice channels (telephone calls). 
Additionally you can answer an incoming phone call on a VoIP account, even while someone 
else is using the account for a phone call.

The Prestige can use the following voice codecs (coder/decoders).

• G.711
• G.729

Voice Activity Detection (VAD) reduces the bandwidth that a call uses by not transmitting 
“silent packets” when you are not speaking. 

When the Prestige uses VAD, it generates and sends comfort (background) noise when you are 
not speaking.

The Prestige supports G.168, an ITU-T standard for eliminating the echo caused by the sound 
of your voice reverberating in the telephone receiver while you talk.

Quality of Service (QoS) mechanisms help to provide better service on a per-flow basis. The 
Prestige supports Type of Service (ToS) and Differentiated Services (DiffServ). This allows 
the Prestige to tag voice frames so they can be prioritized over the network.

The Prestige 2602HW is a SIP Application Layer Gateway (ALG). It allows VoIP calls to pass 
through NAT. 

Auto-provisioning automatically updates your Prestige’s configurable settings via a TFTP 
server.