Configuring the device

The following table provides a summary of the information required for configuration and where it can be entered. Basically, all that is needed is a SIP PBX line for each location that is correspondingly setup at the remote location

Configuring the LANCOM in detail:

1. Under LANconfig, start the setup wizard for configuring the Voice Call Manager. Enable the options SIP provider, SIP phone system and ISDN phone system.
   
   
   
   
   
2. Configure the device as described in the preceding examples:
   • A line to a SIP provider
   • ISDN line with MSN mapping
   • Area and country code for each location
3. Enter a unique domain for the local VoIP domain which describes the local VoIP area for the site. Both sites use different VoIP domains, e.g. location_A.internal and location_B.internal.
4. Configure the line to the SIP PBX with the following values:
   • SIP PBX line name: Unique name for the line to the remote site.
   • PBX SIP domain/realm: Internal VoIP domain of the remote site.
   • Registrar (FQDN or IP): Address for the LANCOM at the remote site, in the event that the device cannot be identified via DNS resolution of the VoIP domain (PBX SIP domain/realm).
     Note: Use the private IP address that can be reached via VPN for the LANCOM here, not the public IP.
   • Leave the field for the shared password empty when registering to the SIP PBX.
   • Leave the field for the public PBX number empty.
5. The call routing table suggested by the setup wizard automatically allows international and national long distance calls to be made via the remote site's line, local calls are routed via ISDN. In addition, a default route directs all numbers which cannot be resolved to the remote site's line.
   
   
   
   
   
6. Adapt the suggested call routing table in order to make international and national long distance calls via the SIP provider line with backup over ISDN. When doing so, please observe that the 0 preceding the number needs to be removed.
   
   
   
   
   
   After adaptation for international and national long distance calls, the call routing table appears as follows:
   
   
   
   
   
7. In this state, all calls that cannot be resolved by the call routing table and which do not have a corresponding entry in the local user list are automatically forwarded to the remote site. If this is not desired, for example where more than two sites are connected in this way, an additional entry can be used to detect the internal calls to a particular site. To achieve this, make a new entry (for the number range 20 to 29 at site B) in the call routing table with the following values:
   • Called number / name: e.g. 2# for all numbers that begin with a 2.
   • Number / name: The called number is used unchanged as a destination number, e.g. in this case 2#.
   • Line: Enter the SIP PBX line for the remote location here, i.e. LOCATION_B.
   In doing so, the default route is adjusted so that all numbers which cannot be resolved are transmitted via ISDN. After adaptation, the call routing table appears as follows:
   
   
   
   
   
   Note: This entry for LOCATION_B is placed well down toward the end of the call routing table so as not to affect the more general rules. However, for interaction with the other routes, verify that only the internal numbers for the remote site are directed to the respective line.