Cisco Cisco TelePresence Video Communication Server Expressway
Enabling endpoints registered on the video network to call Lync clients registered on Lync Server
Cisco VCS Deployment Guide: Microsoft Lync 2010 and Cisco VCS X6.1
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Note: Static routes should be set up for all domains handled by the Cisco VCS.
If Lync Server tries to route a call to the domain shared between Lync Server and Cisco VCS:
- Lync Server will first check all its registrations, both Lync Server registrations and OCS Relay
FindMe™ registrations registered to Lync Server. If any registration is found that matches the
called URI the call will be sent to that device, or if multiple registrations exist, the call will be
forked to all registered devices that match the URI.
- If there is no registration Lync Server will then check the static domain routes and if there is one
for this domain Lync Server will route the call to the destination specified.
- Lync Server will first check all its registrations, both Lync Server registrations and OCS Relay
FindMe™ registrations registered to Lync Server. If any registration is found that matches the
called URI the call will be sent to that device, or if multiple registrations exist, the call will be
forked to all registered devices that match the URI.
- If there is no registration Lync Server will then check the static domain routes and if there is one
for this domain Lync Server will route the call to the destination specified.
If Lync Server tries to route a call to a domain that is not shared between Lync Server and Cisco
VCS:
- Lync Server will check the static domain routes and if there is one for this domain Lync Server
will route the call to the destination specified.
VCS:
- Lync Server will check the static domain routes and if there is one for this domain Lync Server
will route the call to the destination specified.
Although the primary access to end users registered on Cisco VCS may be via a specific domain,
providing static routes for other domains handled by Cisco VCS means that:
providing static routes for other domains handled by Cisco VCS means that:
Endpoints in different domains that may call Lync Server can be called back using their ‘caller ID’
which may have a domain other than the primary domain.
which may have a domain other than the primary domain.
When using OCS Relay and Lync Server and Cisco VCS have the same domain for registered
devices, devices like MCUs and ISDN gateways which may register IDs in the same domain as
Lync, Server but not have FindMe™ IDs associated with them (e.g. because they are ad hoc
conferences) will be able to be called by Lync Server.
devices, devices like MCUs and ISDN gateways which may register IDs in the same domain as
Lync, Server but not have FindMe™ IDs associated with them (e.g. because they are ad hoc
conferences) will be able to be called by Lync Server.
Configure Lync Server to make media encryption optional
By default Lync Server mandates the use of encrypted media. The headers used in Lync Server
SRTP, however, are different from those used by video network devices. Calls between the video
network and Lync Server must therefore use unencrypted media, unless you are using Cisco VCS
version X6.1 with the Enhanced OCS Collaboration option key and the connection between the
Cisco VCS and Lync Server is TLS.
SRTP, however, are different from those used by video network devices. Calls between the video
network and Lync Server must therefore use unencrypted media, unless you are using Cisco VCS
version X6.1 with the Enhanced OCS Collaboration option key and the connection between the
Cisco VCS and Lync Server is TLS.
If the Cisco VCS is not using the Enhanced OCS Collaboration option key or is not connected to
Lync Server via TLS, then the Microsoft Lync Server 2010 zone configuration in the “Lync gateway”
Cisco VCS(s) handles the signaling to ensure that media encryption is not negotiated. Lync Server
needs to be configured to accept calls where media is not encrypted.
Lync Server via TLS, then the Microsoft Lync Server 2010 zone configuration in the “Lync gateway”
Cisco VCS(s) handles the signaling to ensure that media encryption is not negotiated. Lync Server
needs to be configured to accept calls where media is not encrypted.
On Lync Server:
1. Select Start > All Programs > Microsoft Lync Server 2010 > Lync Server Management Shell.
2. Allow encryption to be negotiated
•
Use the command “set-CsMediaConfiguration –EncryptionLevel
supportencryption
supportencryption
”.
Note:
This parameter is a value communicated to Lync clients to affect its operation. To activate this
change on a Lync client, the Lync client must be logged off and logged back in again.
It may take a while for the parameter to be shared throughout the pool (up to an hour) so you
may have to wait a while before restarting the Lync clients for them take on the new value.
change on a Lync client, the Lync client must be logged off and logged back in again.
It may take a while for the parameter to be shared throughout the pool (up to an hour) so you
may have to wait a while before restarting the Lync clients for them take on the new value.
If the Enhanced OCS Collaboration option key is installed and the connection between the
Cisco VCS and Lync Server is TLS, then the default setting of the command set-
CsMediaConfiguration –EncryptionLevel RequireEncryption may be used. However, be aware
that if RequireEncryption is set, any calls with video endpoints that do not support encryption
will fail – in this case SupportEncryption should be used instead.
Cisco VCS and Lync Server is TLS, then the default setting of the command set-
CsMediaConfiguration –EncryptionLevel RequireEncryption may be used. However, be aware
that if RequireEncryption is set, any calls with video endpoints that do not support encryption
will fail – in this case SupportEncryption should be used instead.