Cisco Cisco Expressway
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Media between the Lync client and the B2BUA can be routed in a number of ways, depending on the ICE
(Interactive Connectivity Establishment) negotiation between the Lync client and the B2BUA. The options
(dotted red lines on the diagram) are:
(Interactive Connectivity Establishment) negotiation between the Lync client and the B2BUA. The options
(dotted red lines on the diagram) are:
a.
Lync Client - Expressway-E - Lync Edge - Gateway Expressway - SIP endpoint
b.
Lync Client - Expressway-E - Gateway Expressway - SIP endpoint
c.
Lync Client - Lync Edge - Gateway Expressway - SIP endpoint
d.
Lync Client - Lync Edge - Expressway-E - Gateway Expressway - SIP endpoint
Note:
The exact media path for any particular call is impossible to determine until the call is made. This is
because the clients perform the connectivity checks and candidate sorting each time the media path is
established, and route selection is based on loosely regulated factors. See
established, and route selection is based on loosely regulated factors. See
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Media is connected directly between the internal SIP endpoint and the B2BUA (because the call is SIP to SIP).
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Calls made in the opposite direction, internal video endpoint to external Lync client will use the same signaling
and media paths.
and media paths.
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Cisco Expressway with Microsoft Lync Deployment Guide