Cisco Cisco Expressway
‡ The CE1100 appliance operates with Medium capacity if you install 1 Gbps NICs, or with Large capacity if you
install 10 Gbps NICs.
install 10 Gbps NICs.
These numbers were chosen conservatively. They are based on the additional CPU load caused by transcoding 1920
by 1080 screens while the Gateway Expressway was processing 100 concurrent 720p video calls from Lync.
by 1080 screens while the Gateway Expressway was processing 100 concurrent 720p video calls from Lync.
If you want to increase the maximum number of sessions, consider the following:
■
A screen share transcoding session requires more media ports than a video call, so you may need to increase
the media port range; the default range accommodates 100 video calls, 20 of which are sharing their desktop.
the media port range; the default range accommodates 100 video calls, 20 of which are sharing their desktop.
■
Screen share transcoding loads the CPU more heavily than video (AV) calls. Testing shows that CPU load
increases in a roughly linear way when increasing the number of transcode sessions. There is a similar
characteristic when increasing the number of AV calls without screen sharing, so you should be able to get
more shares if the Expressway is processing fewer concurrent AV calls overall.
increases in a roughly linear way when increasing the number of transcode sessions. There is a similar
characteristic when increasing the number of AV calls without screen sharing, so you should be able to get
more shares if the Expressway is processing fewer concurrent AV calls overall.
■
Higher resolutions and/or multiple monitors also affect performance. The transcoder will output the same
resolution that it receives from Lync, up to a maximum resolution of 1920x1200. Beyond that, the transcoder
will scale the shared screen down to fit within 1920x1200. If the received resolution exceeds 3840x2160, the
transcoder crops the screen to fit within that resolution before scaling it down. The transcoder will also scale
down if it needs to respond to constraints on resources, for example, bandwidth limitations.
resolution that it receives from Lync, up to a maximum resolution of 1920x1200. Beyond that, the transcoder
will scale the shared screen down to fit within 1920x1200. If the received resolution exceeds 3840x2160, the
transcoder crops the screen to fit within that resolution before scaling it down. The transcoder will also scale
down if it needs to respond to constraints on resources, for example, bandwidth limitations.
Screen Sharing Deployments
The following deployments support screen sharing from Lync:
Figure 2 Lync environment to conference managed by TelePresence Conductor trunked to Unified CM
Figure 3 Lync environment to SIP endpoint registered to Unified CM
Notes:
1.
If you are using the Optimize Resources feature with Lync screen sharing, you need TelePresence Conductor
version XC4.0 or later.
version XC4.0 or later.
2.
If you are using the Optimize Resources feature with Lync screen sharing, you need TelePresence Server
version 4.2 or later.
version 4.2 or later.
3.
Requires Cisco VCS Control for H.323 registrations, not shown in the diagram.
Lync Environment
The scale of your Lync deployment could mean that your deployment model is more complex than what is described
in this guide.
in this guide.
describes some of the different options and how the
deployment model will vary in each case.
Lync Client Versions
Expressway is generally compatible with Lync 2010 and Lync 2013 clients, including mobile clients. When specific
issues are discovered, they are recorded on the
issues are discovered, they are recorded on the
Lync 2013 for Windows and Lync 2010 for Windows can call Unified CM-registered endpoints. Lync 2011 for Mac
cannot do this, it uses an unsupported video codec.
cannot do this, it uses an unsupported video codec.
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Cisco Expressway with Microsoft Lync Deployment Guide