Nortel Networks 1000S Manuale Utente

 System architecture

The Terminal Proxy Server (TPS) acts as a signaling gateway between the IP 
Phones and the Call Server using the UNIStim protocol. It performs the 
following functions:

•

converts the IP Phone UNIStim messages into messages the Call Server 
can interpret

•

allows IP Phones to access telephony features provided by the Call 
Server

The TPS also controls the IP Phone registration.

SIP/H.323 Signaling Gateways are software components configured on 
virtual loops, similar to IP Phones. SIP/H.323 Signaling Gateways bridge 
existing call processing features and the IP network. They also enable access 
to the routing and features in the MCDN feature set.

Note 1: The SIP/H.323 Signaling Gateway must register with the 
Network Routing Service (NRS).

Note 2:  Virtual TNs enable you to configure service data without 
hardwiring IP Phones to the CS 1000S system. Virtual TNs are 
configured in LD 97.

To support IP Peer Networking, dual Call Servers in a CS 1000S must be 
associated with Signaling Servers that run SIP/H.323 Signaling Gateway 
software. The number of Signaling Servers required depends on the capacity 
and level of redundancy required.

The NRS application provides network-based routing, combining the 
following into a single application:

•

H.323 Gatekeeper — The H.323 Gatekeeper provides central dialing 
plan management and routing for H.323-based endpoints and gateways.

•

SIP Redirect Server — The SIP Redirect Server provides central 
dialing plan management and routing for SIP-based endpoints and 
gateways.