Talkswitch 48-CVA - Manual (Page 6)

The TalkSwitch 48-CVA is a hybrid PSTN/VoIP phone system. The addition of VoIP to
the TalkSwitch product line adds the ability to use a broadband IP connection for
voice calls.
The TalkSwitch 48-CVA can be used in many different applications. The most popu-
lar configurations are multi-branch, teleworker integration and service provider
integration.
H Ho ow w d do oeess V Vo oIIP P w wo orrk k??
Voce over IP, or VoIP, sends calls over the Internet or any Internet Protocol (IP) net-
work by converting voice traffic into data packets. These packets are then routed over
the IP network in the same way as other data, reassembled at the point of arrival, and
then converted back to voice.
D Do oeess a a V Vo oIIP P cca allll sso ou un nd d lliik kee a a rreeg gu ulla arr p ph ho on nee cca allll??
Under the right conditions, VoIP calls can sound as good or even better than regular
phone calls. Voice quality is affected by numerous issues, including how it is com-
pressed for delivery over the Internet, decompressed, and how packets are processed.
A few steps can help ensure call quality.
1) High-speed connections on both ends of the call: Good quality VoIP is not pos-
sible over a dial-up modem connection. To support more simultaneous VoIP
calls, a broadband connection is required. Please visit our site at
www.talkswitch.com/voip/voip_test.php to determine what your Internet con-
nection can support.
2) Choose the right CODEC for your location: TalkSwitch supports 3 CODECs
(compression algorithms). The default CODEC is G.729 which uses approxi-
mately 20Kbps bandwidth upstream and 20Kbps bandwidth downstream for
each call. G.729 provides very good call quality while minimizing bandwidth
usage.
1
i 1.0 Introduction
Introduction
to VoIP
TS manual 11th ED_CVA_v11_CD_Release.qxd 7/13/2004 3:33 PM Page i