1.1 Information about IP Telephony Service
The Virtual 16-Channel SIP CO Line Card (V-SIPGW16) is a virtual CO line card which is designed to be easily
integrated into an Internet Telephony Service provided by an ITSP (Internet Telephony Service Provider).
As a major SIP Provider, an ITSP provides its telephony service partly through the conventional telephone
network (e.g., ISDN and Mobile), which is fee-based. An ISP (Internet Service Provider), another major SIP
Provider, does not provide telephone connection itself. However, providing its users with Internet access, an
ISP provides voice communication on the Internet for free. In this way, with VoIP technology based on the SIP
protocol, the cost of voice communication can be much cheaper than conventional telephone networks.
The maximum of two V-SIPGW16 cards can be installed to the virtual CO line slots of the PBX. Therefore, the
channel capacity of the card allows users to connect to up to 32 each different ISP/ITSPs.
V-SIPGW16 Connection Outline
The following diagram illustrates a simple VoIP network connecting the V-SIPGW16 card to the Internet.
PBX with
V-SIPGW16 Card
PC
LAN
(Local Area Network)
WAN (Wide Area Network)
Internet
Local
Telephone
IP-PT
ISP
ITSP
Router
Switching
Hub
Requirements for Internet Telephony Service
•
You need to subscribe with an ISP for Internet connection.
•
You need to subscribe with an ITSP for telephone connection. The ISP and ITSP may be part of the same
company.
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Programming Manual for Virtual SIP CO Line Card
Document Version 2008-11
1.1 Information about IP Telephony Service
