Mike's PBX Cookbook

CS1000 Architecture


Call Server Holds Customer Database
Processes Calls
▲ ELAN ▼


Terminal Proxy Server (TPS) Links IP Sets to Call Server
Uses UNISTIM protocol (propietary Nortel)
H323 & SIP Signalling Gateway Standards based signalling for Virtual Trunks
Network Routing
Service (NRS)
Resolves DN to IP addresses for H323/SIP and UNISTIM
SIP Redirect Server
H.323 Gatekeeper
UNISTIM Network Connect Server (NCS)
Personal Directory Directory of up to 100 names and numbers per IP Set user
Element Manager GUI for Call Server and NRS Management
▲ ELAN ▼         ▲ TLAN ▼
Media Gateway(s) Houses IPE Cards
Provides IP to TDM conversion via Media Cards

IP Network:

There are two networks, plus a High Speed Pipe (HA only).

ELANThe Equipment LAN (ELAN) is a private management network for CS1K compontents.
The Call Server connects only to the ELAN network.
TLANThe Telephony LAN (TLAN) is the 'public side' where IP trunks and sets are connected.
It may also be referred to as the Customer LAN (CLAN).
HSPHigh Availability (HA) systems use a High-Speed Pipe to link both Call Server cores.


Call Server:

Note: IP sets reside on the TLAN, or a network attached to it. They need to communicate with the Call Server (on the ELAN) in order to make and receive calls. This is acomplished by registering with the Signalling Server.

Signalling Server:

Media Gateway(s):

Call Flow:

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