The tutorial discuss configuration steps that are needed to connect Headquarters and Branch office using SIP trunk. It is only showing configuration required to be done on Cisco Unified Communications Manager (CUCM) that is located in the Branch office. The configuration of CUCM located in Headquarters will be not explained here as it is almost identical to configuration done on Branch office CUCM.
The network topology diagram is discussed here.
Note: We assume that both CUCMs were previously configured to support local calls. It is discussed in this tutorial.
Branch Office Cisco Unified Communications Manager Configuration
1. Create a New Region, Location and Device Pool Configuration
We are going to create a new region Headquarters-Region and location Headquarters-Location on Branch CUCM. Once we create a new device pool Headquarters-pool they both will be added to the new device pool.The device pool will be later configured on SIP trunk.
a) Headquarters-region
Navigate to System -> Region. Click Add New button. Type new region name - Headquarters-Region then click on Save button. Click Branch-Region in Regions settings and select an option 8kbps (G.729) from Max Audio Rate column. Thanks to this setting, G.729 codec will be used for calls between Headquarters and Branch office.
Now click Headquarters-region and select 64kbps (G.722,G.711) option. One of this these codecs will be used if phone call is made between Branch office extensions.
Click Save button to save settings. Region relationship between Headquarters and Branch office is shown on the picture below.
Picture 1 - Headquarters Region Configuration and its Relationship to Branch Region
b) Headquarters-Location
Navigate to System -> Location. Click Add New button and type Headquarters-location. Limit audio bandwidth for Headquarters-location to 2048 kbps. This setting watches an overall bandwidth allocated for phone calls. If a phone new call is placed from Branch to Headquarters extension and bandwidth limit 2048 kbps is exceeded CUCM will reject the call.
c) Headquarters-Pool
Navigate to System -> Device Pool. Click Add New button and configure following parameters.
Device Pool Name -> Headquarters-Pool
Cisco Unified Communications Manager Group -> Branch-Group
Date/Time Group -> CMLocal
Region -> Headquarters-Region
Media Resource Group List -> Branch-MRGL-I
Location -> Headquarters-Location
Network Locale -> Slovakia
2. SIP Trunk, Route Group and Route List Configuration
In this step a new device - SIP trunk Branch-Trunk-Headquarters will be created. Then the route group Branch-RG-Headquarters will be created and the trunk added to the route group. The last step consists of creating Route list Branch-RL-Headquarters. The route list will be populated with Route Group Branch-RG-Headquarters.
a) SIP trunk
Navigate to Device -> Trunk. Click Add New button. Select Trunk Type -> SIP trunk. Click Next button and configure following parameters.
Device Name -> Branch-Trunk-Headquarters
Description -> Trunk to Headquarters
Device Pool -> Headquarters-Pool
Media Resource Group List -> Branch-MRGL-I
Location -> Headquarters-Location
Check tbe box Media Termination Point Required
SIP Information -> Destination Address 192.168.200.252
SIP Trunk Security Profile -> Non Secure Trunk Profile
SIP Profile -> Standard SIP Profile
Click Save button.
b) Route group
The next step is adding SIP trunk to Route Group.
Navigate to Call Routing -> Route/Hunt -> Route Group. Click Add New button and create a route group Branch-RG-Headquarters. Click Add to Route Group button to add trunk Branch-Trunk-Headquarters to the route group.
Picture 2 - Adding SIP Trunk to Route Group
c) Route List
Navigate to Call Routing -> Route/Hunt -> Route List. Click Add New button and create a new route list Branch-RL-Headquarters. Select Cisco Unified Communications Manager Group -> Branch-Group and click Save button. You will be redirected to Route List configuration window. Click Add Route Group button and select Branch-RG-Headquarters route group. Then click Save button again. You should be able to get the output shown on the picture below.
Picture 3 - Adding Route Group to Route List
3. Route Pattern Configuration
Navigate to Call Routing -> Route/Hunt -> Route Pattern. Click Add New button and create route pattern with the following parameters.
Route Pattern -> 40[01]x
Description -> Route pattern to Headquarters CUCM-II
Gateway/Route List -> Branch-RL-Headquarters
Click Save button.
Headquarters Cisco Unified Communications Manager Configuration
So far we have configured Branch office CUCM to support phone calls between Branch and Headquarters locations. We must make similar configuration for CUCM located in Headquarters. The only main difference is the route pattern configuration as we have to configure pattern 30[01]x to direct phone calls to Branch office extensions. The other differences are only cosmetic.