T-Comfort Comfort Pro S, Руководство по монтажу и пусконаладке

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Voice over IP (VoIP) SIP Telephony
SIP Telephony
The SIP Internet (Session Initiation Protocol) protocol provides you with a low-cost, standardised option for
telephoning via IP-based networks. The Comfort Pro S enables you to use external SIP telephone
connections (“SIP trunk lines”). Furthermore, internal SIP subscribers, SIP telephones or SIP telephony
software are also supported (see also Quick Start : External SIP Line starting on page 94 and Internal SIP
Telephony starting on page 95).
External SIP Connections
The Telephony : Trunks : Route menu gives you the option to configure a bundle overflow, which
automatically occupies a second line in case of a breakdown or over-occupancy of the SIP connection. You
can also set up your system to route certain types of calls, such as international calls, to an SIP connection.
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Note: You will need a Media Gateway card for SIP telephony.
You will also need a fast Internet connection such as DSL for SIP telephony.
You will also usually need the services of a SIP provider. A SIP provider operates a special server (the SIP
Registrar) to handle connections. The SIP provider also operates a gateway to the ordinary telephone network
which users pay to use and which enables the SIP provider to provide calls to the telephone network. A SIP
connection can also accept incoming calls from the telephone network.
The same voice transmission techniques as those explained in Fundamentals starting on page 97 are used
for SIP telephony. SIP telephony has the following distinctive features:
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Subscribers are identified through an e-mail-like “SIP ID” such as 12345@domain.net or name@sip-
provider.com.
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SIP transmits dialling numbers always in a single data package (block dialling). Dialling can therefore be
concluded with the hash key
#
on the system terminal, or the end of the number will be indicated by a
time-out. The value for this time-out can be defined for each SIP provider separately.
■
You must log on (“Login”) to the SIP registrar before you can use SIP telephony. Use the Comfort Pro S to
manage important information for the registration (user name and password) of one or more SIP
accounts. It is possible to make several calls simultaneously using a single SIP account.