Microsoft Teams with Local Media Optimization

The device can be configured to support the Local Media Optimization feature when deployed in a Microsoft Teams environment. This feature is intended for complex environments consisting of a central SBC device (i.e., this device that you are configuring), which is referred to by Microsoft as the Proxy SBC, integrated in the Teams environment, and multiple remote SBCs or Gateways (referred to by Microsoft as remote site SBCs). In this environment, the central SBC determines the optimal path for connecting calls between the Teams clients, based on network connectivity (good or bad) and voice quality. The device path selection is based on supplementary information provided by Microsoft using their proprietary headers that are included in the SIP messages during call setup between Teams clients:

Microsoft SIP Header

Value

Description

X-MS-UserLocation

Internal or External

Indicates if the Teams client is located in the internal or external network with respect to the central SBC. Based on the header value, the device selects the Media Realm, using the IP Group's 'Internal Media Realm' or 'Media Realm' parameters, respectively.

X-MS-MediaPath

sbc1.contoso.com

sbc2.contoso.com

...

Indicates the order of remote SBCs that should be used for the media path between the Teams clients. If the first address is the central SBC itself, the media traverses the device (non-direct media).

X-MS-UserSite

usersiteID

Indicates the name of the Teams site in which the Teams client is located.

Configuration of the device for Local Media Optimization is done on the IP Group of the Teams client, using the following IP Group table parameters:

'Teams Local Media Optimization Handling': Enables Local Media Optimization and defines how the device handles the Teams call based on the Microsoft proprietary SIP headers.
'Internal Media Realm': Assigns a Media Realm which is used if the X-MS-UserLocation header value is "Internal". If the header value is "External" (or not present), the Media Realm assigned by the 'Media Realm' parameter is used.
'Teams Local Media Optimization Initial Behavior': Defines how the central SBC device initially sends the received INVITE message with the SDP Offer to Teams.
'Teams Local Media Optimization Site' : Defines the name of the Teams site (e.g., "Singapore") to which the IP Group (Teams client) belongs. The Teams site is indicated in the SIP header, X-MS-UserSite of the incoming SIP message received from the Teams client. The device searches the Dial Plan, specified by the 'Regions Connectivity Dial Plan' parameter, to check if this IP Group's Teams site and the Teams site of the destination IP Group share a common group number. If they do share a group number, the device processes the call as a direct media (bypass) call. For more information, see Using Dial Plans for Microsoft Local Media Optimization.

For more information on the above parameters, see their descriptions in Configuring IP Groups.

For detailed technical information on deploying the device in a Microsoft Teams environment with Local Media Optimization, contact your AudioCodes sales representative.

For detailed configuration of Microsoft Teams Direct Routing for enterprises with AudioCodes SBC, refer to Connecting AudioCodes' SBC to Microsoft Teams Direct Routing Enterprise Model.
This section is applicable only to the SBC application.