This recording method utilizes special features of the Cisco Unified Communication Manager introduced in version 6.0. It integrates call recording and silent monitoring features into CUCM. If an extension is configured for recording (the configuration is available in the CUCM), the CUCM instructs the phone to send the RTP streams related to a given call, directly to the recording server utilizing the built-in bridge of the phone. The recording system is connected to the CUCM via a SIP trunk to capture the signaling messages. Additional call detail information is obtained by using a JTAPI interface.
You can also use this technology for silent monitoring, even without call recording, see Central silent monitoring utilizing RTP forking in Cisco environment.
- In a multi-site network, branches where few calls have to be recorded, the deployment of a recorder does not require a dedicated recording server for each remote site.
- Theoretically, this recorder eliminates the complexity of the switching infrastructure compared to the passive recording method, because the RTP streams are sent directly to the recording server automatically.
- Can be easily scaled by adding new recorders to the system if more capacity is required.
- Does not require extra DSP resources from the network compared to the active (conference based) method.
- Recording tone can be generated by the phone.
- Encrypted calls can be recorded since CUCM 8.0
- Requires additional bandwidth on the network to the recording server(s).
- Since the recording functionality is controlled by the CUCM, in case of a WAN link failure, the recording will not work at all in the branch offices (if the CUCM is in the central site).
- Cisco SRST (Survivable Remote Site Telephony) does not support native recording.
- Requires at least CUCM version 6.0.
- Does not support all phone types (check the list above)
- Requires extra capacity from the CUCM server(s) (for each recording session add 2 calls to BHCC in your dimensioning calculation).
- Only voice calls are supported.
"Almost" all Cisco phones support central recording
The Verba passive, network spanning / traffic monitoring based recording engine technology supports all Cisco phones, however, the Verba central recording technology needs cooperation from software built into the Cisco phones to deliver the recording function. Not all Cisco phones support this recording mode, one requirement is the build-in-bridge technology in the phone.
Cisco maintains a detailed support matrix for RTP-forking based recording and silent monitoring: Unified CM Recording and Silent Monitoring Supported Device Matrix
You can also check the supported devices for specific CUCM versions: https://www.cisco.com/c/dam/en/us/td/docs/voice_ip_comm/uc_system/unified/communications/system/Compatibility/CSR-Compatibility-Matrix-InteractiveHTML.html
Supported Cisco Unified Communications Manager versions: 6.x, 7.x, 8.x, 9.x,10.x, 11.x and 12.x
Supported Cisco IP phones (certain phones are only supported on the latest CUCM versions, please check the links above or run a report (see below) on your CUCM for latest information):
- Cisco 7832
Cisco 7914 Sidecar
Cisco 7915 Sidecar
- Cisco 7916 Sidecar
Cisco CKEM Sidecar
- Cisco 8821
- Cisco DX70
- Cisco DX80
Cisco IP Communicator
Cisco Jabber for Windows
Cisco Jabber for Mac
Cisco Jabber for Android
Cisco Jabber for IOS
Find out what phones are supported on your system
To find out which phones are supported on your CUCM version, use the built-in reporting tool:
Step 1 Login to Cisco Unified Reporting on CUCM admin screen.
Step 2 From System Reports select Unified CM Phone Feature List.
Step 3 Select Feature: Record. This will list all phones capable to do RTP forking.
Encrypted call recording support matrix
Cisco Unified Communications Manager 8.0 supports the recording of encrypted calls via the RTP forking based interface. The following table helps you to identify supported call scenarios regarding the encryption feature.
|Non Secure Recorded Phone||Authenticated Recorded Phone||Secure Recorded Phone|
|Non Secure SIP trunk to the recorder||Supported||Not supported||Not supported|
|Encrypted SIP trunk to the recorder||Supported, but the forked RTP will not be encrypted||Not supported||Supported|
Possible deployment of Cisco Central call recording with RTP forking:
- Single server solution: All Verba services (Administration, Recorder) are on one server. It is recommended only for a few user POC or trial deployment (10-20 users).
For the installation guide see: Installing a Verba Single Server solution
- Media Reposiroty + Recorder Server: The Verba administration/storage server is deployed separately from the recorder.
For the installation guide see: Installing a Verba Media Repository and Installing a Verba Recording Server