List of terms Page 253 of 258
Transport Control Protocol (TCP), which establishes a virtual connection between a destination and a source.
IP by itself is something like the postal system. It enables you to address a package and drop it in the system, but there's no direct link between you and the recipient. TCP/IP, on the other hand, establishes a connection between two hosts so that they can send messages back and forth for a period of time.
LAN
Local Area Network.
Local Mode
The SRG is in Local Mode when:
•The IP Phones are first installed and not yet reregistered with the main office
•The SRG cannot communicate with the main office and the IP Phones are reregistered with the SRG
•A user deliberately puts the IP Phone in the Test Local Mode condition.
Main office
The CS 1000 system that has been programmed to accept redirection of the SRG IP Phones and provide call service for the SRG in Normal Mode.
NCS
Network Connection Service. It provides a TPS interface to the NRS, allowing the TPS to query the NRS using the UNIStim protocol. It is required to support the main office, branch office, Virtual Office, and Geographic Redundancy features.
Normal Mode
The SRG is in Normal Mode when the IP Phones on the SRG are correctly redirected to the main office Call Server.
NRS
Network Routing Service. The software application where all systems in the network are registered. The NRS consists of the H.323 Gatekeeper and the Network Connection Service (NCS).
Main Office Configuration for Survivable Remote Gateway 50 Configuration Guide
