Overview Page 19 of 254Main Office Configuration for SRG200/400 Release 1.5 Configuration GuideThe diagrams throughout this documentation show a CS 1000S main office.All of the systems appearing in the list perform identical main officefunctions as far as the SRG is concerned. For information about the SRG, seethe SRG200/400 Release 1.5 Configuration Guide.Signaling ServerThe Signaling Server is required at the main office only. It provides thefollowing functions:• Terminal Proxy Server (TPS)— The TPS provides a connection from the IP Phones to the CallServer. It also provides a connection path from a virtual trunk to theCall Server.• Web server for Element Manager and Network Routing Service (NRS)ManagerA second Signaling Server can be used to provide redundancy in the case offailure in the primary Signaling Server at the main office.A similar function to the Signaling Server exists at the SRG.The Signaling Server supports en bloc signaling, which is standard on theSignaling Server.For more information about the Signaling Server, see Signaling ServerInstallation and Commissioning (NN43001-312). For more informationabout H.323, see IP Peer Networking Installation and Commissioning(NN43001-313).Network Routing ServiceThe NRS application provides network-based routing, combining thefollowing into a single application:• H.323 Gatekeeper — provides central dialing plan management androuting for H.323-based endpoints and gateways.NRS also contains SIP Redirect Server but SIP Trunks are not supportedon an SRG.
