Specifications
MBG Engineering Guidelines, Release 8.0
6 Call Recording
MBG includes the ability to act as a secure man-in-the-middle for SRTP voice streams, enabling a third-party call
recording solution to tap calls by using MBG’s SRC interface.
Please see the section on Sizing Your Installation to determine performance limits and resource requirements.
6.1 Call recording vs. Local streaming
Mitel Border Gateway supports both Local Streaming and Call Recording, both of which can be enabled or
disabled for individual users. These options are not compatible.
Local Streaming is a generally desirable feature that reduces bandwidth needed for voice/video calls by allowing
the RTP stream(s) to bypass the MBG when two devices are able to communicate directly. However, this means
such calls cannot be recorded. If both Local Streaming and Call Recording are enabled on a device, Call
Recording wins. All streams to and from that device will go through MBG so they can be recorded.
6.2 Indirect Call Recording
Indirect Call Recording (ICR), introduced in MBG 7.1, is a feature supported by Mitel's 53XX series IP sets and
MCD software release 5.0 SP1 and up. It also has only limited support from CRE vendors.
With ICR in place, SRC can support recording of any supported sets that are connected to any supported MCD
without having to reconfigure the sets to connect through SRC, as is the case with “direct” call recording. SRC
can be configured with a mix of both ICR and "direct" call recording. This would be required if non-supported
sets or MCDs are deployed.
Using ICR allows for some cost reductions and more network flexibility in certain call recording deployments. It is
especially applicable for network deployments where centralized call recording is desired in a network situation
where remote, WAN-connected sets are connected to remote office MCD's.
When MBG is deployed in the DMZ, the corporate firewall protecting the DMZ requires the following rules (in
addition to the common rules found in Firewalls (DMZ deployment)) to support Indirect Call Recording:
From the MBG server to the ICPs:
• allow protocol TCP, destination port 6815 (and return traffic)
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