System information

4-10 INSTALLING TELEVANTAGE
VoIP requirements ________________________________________
TeleVantage supports two protocols for voice communication over the Internet.
Q Session Initiation Protocol (SIP). Developed by the Internet Engineering Task Force
(IETF) specifically for Internet use, SIP is a well-accepted standard for Voice over
Internet Protocol (VoIP) communication. SIP enables VoIP communication with other
SIP-compatible devices, including SIP desktop phones or softphones, SIP services, and
SIP carriers. For more information, see Chapter 14 in Administering TeleVantage.
Q H.323. Developed by telephone companies, the H.323 protocol enables communication
with H.323-compatible devices, such as some VoIP phones, and H.323-based terminals
such as Microsoft NetMeeting. For more information, see Chapter 15 in Administering
TeleVantage .
Placing VoIP calls over the Internet or your private TCP/IP network does not require additional
telephone company trunks. Instead, Dialogic Internet telephony resources must be installed on
the TeleVantage Server. Telephony resources can be provided in two ways as described on page
3-3.
VoIP also requires the following:
Q The TeleVantage Server PC must have an always-on, preferably high-speed connection
to the Internet.
Q You must use a static IP address for the NIC that handles VoIP RTP audio traffic on the
TeleVantage Server PC. For more information, see “Network interface card
requirements” on page 3-9.
VoIP features in TeleVantage
TeleVantage supports VoIP in the following ways. See “Configuring TeleVantage Internet
telephony” in Chapter 14 in Administering TeleVantage for configuration requirements.
Q TeleVantage Enterprise Gateways. By configuring TeleVantage Enterprise Gateways
on two or more TeleVantage Servers, users on one TeleVantage Server can make calls
over the Internet or your private TCP/IP network as if they were on the other
TeleVantage Server. See “Connecting two Servers using TeleVantage Gateways” in
Chapter 15 in Administering TeleVantage.
Q SIP carrier support. SIP carriers, also known as Internet telephony service providers
(ITSPs), provide a VoIP connection to the Public Switched Telephone Network (PSTN)
for a nominal monthly fee. (An example is www.broadvoice.com.)
SIP carriers provide customers with real phone numbers, and deliver calls to those
numbers via VoIP. Likewise, calls to the SIP carrier over VoIP ring PSTN users as calls
coming from those telephone numbers. With a SIP carrier, you do not need a PSTN trunk
on-site in order to place and receive calls, although it is wise to have one in case you
encounter a problem connecting to the SIP carrier over the Internet.