How Does Voip Work; Does A Voip Call Sound Like A Regular Phone Call - Talkswitch 48-CA User Manual

CHAPTER 1
This section applies only to customers using the TalkSwitch 48-CVA. Please proceed to
Section 2 if you have a TalkSwitch 48-CA (non VoIP version).
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 popular
configurations are multi-branch, teleworker integration and service provider
integration.

How does VoIP work?

Voice over IP, or VoIP, sends calls over the Internet or any Internet Protocol (IP)
network 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.

Does a VoIP call sound like a regular phone call?

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
compressed 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 possible
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 connection can support.
2. Choose the right CODEC for your location: TalkSwitch supports 3 CODECs
(compression algorithms). The default CODEC is G.729 which uses approximately
25Kbps bandwidth upstream and 25Kbps bandwidth downstream for each call.
G.729 provides very good call quality while minimizing bandwidth usage.
The G.726 (32Kbps) CODEC is a better quality solution compared to the G.729 CODEC. It
does, however, require more bandwidth per call. A G.726 call will typically require
50Kbps bandwidth upstream and 50Kbps bandwidth downstream for each call.
I n t r o d u c t i o n t o V o I P
Introduction
to VoIP
1