292 Dialing plan configurationThis section primarily describes the configuration of a dialing plan for off-netcalls from MG 1000B IP Phones in Normal Mode. However, the proceduresin this chapter are also applicable when configuring on-net UDP dialing forthese telephones, if a single Access Code is used for both UDP and someor all off-net calls.Introduction The Branch Office feature is versatile enough to provide solutions for a widevariety of applications which require different dialing plans. Therefore, aneffective dialing plan is critical for the successful deployment of a BranchOffice.Nortel recommends that the call type sent to the Virtual Trunk is not a PublicNumber. That is, the number should stay in the Private/Special Numberdomain. This avoids any future conflict with any future Public Number, whichis out of the PBX administrator’s control.Dialing plansWhen a number is dialed, the Call Server determines whether the callednumber is internal or external to the Branch Office. If internal, the systemterminates the call on the appropriate terminal. If external, the systemroutes the call in one of two ways:• Uniform Dialing Plan (UDP) or Coordinated Dialing Plan (CDP) routesthe call to the proper trunk group.• Vacant Number Routing (VNR) routes the call to a Virtual Trunk.Once the call is sent over the IP network, the call is routed to the MG 1000BCore, which uses the Network Routing Service (NRS) to route the call. In aSIP network, the Redirect Server translates the address from a telephonenumber to a SIP URI, and authorizes the call. In an H.323 network, theH.323 Gatekeeper translates the address from a telephone number to anIP address, and authorizes the call.Specific dialing plan configuration is required for IP Phones to properlyselect a main office or Branch Office that provides access to the PSTN forthe originating IP Phone. A common configuration might be:• Branch Users select the MG 1000B PSTN for local calls.• Main office users select the main office PSTN for local calls.• All users select either the main office or MG 1000B PSTN forlong-distance calls to minimize toll charges.However, this configuration represents only one way that the dialing plancould be configured. PSTN calls can be routed according to the point oforigin (main office or Branch Office) and/or the desired destination, and canNortel Communication Server 1000Branch Office Installation and CommissioningNN43001-314 01.02 StandardRelease 5.0 20 June 2007Copyright © 2007, Nortel Networks.
