Page 28 of 254 OverviewNN43001-308 Standard 01.02 May 2007the main office IP Phones or other branches by routing through the localPSTN.Testing the telephone in Local ModeFrom Normal Mode, the branch user has the option of going to Local Modemanually using the Test Local Mode feature, or when the telephone is power-cycled. The test can be performed by the user at any time and does not requirea password. This test is invoked from any IP Phone at the branch office.Nortel recommends testing Local Mode operation after changing theprovisioning for a telephone on the SRG.To ensure that users do not forget to resume Normal Mode operation, theSRG redirects the telephone to the main office to return the telephone toNormal mode. This occurs if the telephone remains registered to the SRG inTest Local Mode for ten minutes (default setting). Alternatively, the user canpress the Quit key on the phone to return to Normal Mode.For further information about Local Mode functionality for SRG, see theSRG200/400 Release 1.5 Configuration Guide.Virtual TrunksIn order for endpoints in the CS1000 network to access endpoints in localmode at the SRG or to access the PSTN at the SRG, Virtual Trunks are usedover the LAN/WAN.Virtual Trunks are software components that provide the trunking features ofthe Meridian Customer-Defined Network (MCDN) feature set. Access toPSTN digital or analog trunks at the branch office occurs through the MCDNVirtual Trunk.IMPORTANT!When a telephone or trunk in the main office calls an SRG IP Phone thathas switched to Local Mode due to WAN failure, the call is treatedaccording to the main office call redirection configuration (such asforwarding to voice mail or continuous ringback).
