Nortel ISDN Signaling Link, Описание, установка и эксплуатация

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ITG Trunk 2.0 ISDN Signaling Link (ISL) Description, Installation and Operation
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ITG Engineering Guidelines
Introduction
The Meridian Integrated IP Telephony Gateway (ITG) system:
• compresses PCM voice
• demodulates Group 3 fax
• routes the packetized data over a private internet, or intranet
• provides virtual analog ISDN signalling link (ISL) TIE trunks between
Meridian 1 ESN nodes.
ITG routes voice traffic over existing private IP network facilities with
available under-used bandwidth on the private Wide Area network (WAN)
backbone.
The ITG is targeted at the Enterprise customer who has both a Meridian 1
system installed for providing corporate voice services, and an intranet for
corporate data services. A customer is expected to use the ITG system to
move traffic from a PSTN-based network to the intranet. Voice and fax
services which depended on circuit-switched and Time Division
Multiplexing technology will be transported using packet-switched and
statistical multiplexing technology.
This chapter provides guidelines for designing a network of ITG nodes over
the corporate intranet. It describes how to qualify the corporate intranet to
support an ITG network, and determine changes required to maintain the
quality of voice services when moving those services from the PSTN. It
addresses requirements for the successful integration with the customer's
existing local area network (LAN). By following these guidelines, you can
design the ITG network so that the cost and quality tradeoff is at best
imperceptible, and at worst within a calculated tolerance.