Polycom Vega Gateway - Manual (Page 16)

Version 2.1 16 March 2006 Page 16 of 33
Vega Gateway Scenarios. ©2005-2006 VegaStream Ltd.
Examples are given in best faith – ensure that you check the capabilities of systems before
deploying them, especially the functionality of devices not designed and delivered by VegaStream.
6. PSTN toll bypass
Aim: To use internet to provide cheap inter-country calling
Vega gateways, together with Application servers supporting pre-paid card services allow
Telephony Network
• E1 Euro ISDN signalling is supported by Vega 400 and Vega 100
• T1 NI1 & NI2 signalling is supported by Vega 400 and Vega 100
• T1 Loop start, Ground start and Wink start CAS signalling is supported by Vega 400 and
Vega 100
• BRI Euro ISDN signalling is supported by Vega 50 BRI
• Analog connection is possible, but is not preferred (for details on analog connectivity see
later section)
IP Network
• Recommend – private IP network between sites
• Can be any reliable IP connection, including leased line, satellite and the internet
• QOS should be implemented if possible to ensure that VoIP packets pass through the
network in a consistent and timely manner and are not discarded by congested routers
• The Internet is often used for carrying the VoIP traffic; contention and available bandwidth
must be considered
User experience
• The caller dials a local, often toll-free or lo-call telephone number and gets routed to a VoIP
gateway. The call is answered by the Application Server and the user is asked to enter
account number, pin and destination phone number. If the caller has sufficient credit the
call is routed through to the most appropriate (Least Cost Routed) destination VoIP
gateway and the gateway presents the call over the PSTN to the required destination
number. If credit runs out during a call then the call can be torn down (terminated).
VoIPon Solutions www.voipon.co.uk [email protected] Tel: +44 (0) 1245 600560