Configuring Quality of Service policies in Lync Server 2013 for clients running on Windows 7 or Windows 8

Topic Last Modified: 2016-03-29

In addition to specifying port ranges for use by your Lync clients you must also create separate Quality of Service policies that will be applied to client computers. (The Quality of Service policies created for Conferencing, Application, and Mediation servers should not be applied to client computers.) This information applies only to computers running the Lync 2013 client and either Windows 7 or Windows 8.

The following example uses this set of port ranges to create an audio policy and a video policy:

To create a Quality of Service audio policy for Windows 7 or Windows 8 computers, first log on to a computer where Group Policy Management has been installed. Open Group Policy Management (click Start, point to Administrative Tools, and then click Group Policy Management) and then complete the following procedure:

1. In Group Policy Management, locate the container where the new policy should be created. For example, if all your client computers are located in an OU named Clients then the new policy should be created in the Client OU.

2. Right-click the appropriate container and then click Create a GPO in this domain, and Link it here.

3. In the New GPO dialog box, type a name for the new Group Policy object in the Name box (for example, Lync Audio) and then click OK.

4. Right-click the newly-created policy and then click Edit.

5. In the Group Policy Management Editor, expand Computer Configuration, expand Policies, expand Windows Settings, right-click Policy-based QoS, and then click Create new policy.

6. In the Policy-based QoS dialog box, on the opening page, type a name for the new policy (e.g., Lync Audio) in the Name box. Select Specify DSCP Value and set the value to 46. Leave Specify Outbound Throttle Rate unselected, and then click Next.

7. On the next page, select Only applications with this executable name and enter the name Lync.exe, and then click Next. This setting instructs the policy to only prioritize matching traffic from the Lync client.

8. On the third page, make sure that both Any source IP address and Any destination IP address are selected and then click Next. These two settings ensure that packets will be managed regardless of which computer (IP address) sent those packets and which computer (IP address) will receive those packets.

9. On page four, select TCP and UDP from the Select the protocol this QoS policy applies to dropdown list. TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are the two networking protocols most-commonly used by Lync Server and its client applications.

10. Under the heading Specify the source port number, select From this source port or range. In the accompanying text box, type the port range reserved for audio transmissions. For example, if you reserved ports 50020 through ports 50039 for audio traffic enter the port range using this format: 50020:50039. Click Finish.

After you have created the QoS policy for audio you should then create a second policy for video. To create a policy for video, follow the same basic procedure you followed when creating the audio policy, making these substitutions:

• Use a different (and unique) policy name (for example, Lync Video).

• Set the DSCP value to 34 instead of 46. (As noted previously, you do not have to use the DSCP value 34; you simply must assign a different DSCP value than the one used for audio.)

• Use the previously-configured port range for video traffic. For example, if you have reserved ports 58000 through 58019 for video, then set the port range to this: 58000:58019.

If you decide to create a policy for managing application sharing traffic make these substitutions:

• Use a different (and unique) policy name (for example, Lync Server Application Sharing).

• Set the DSCP value to 24 instead of 46. (Again, this value does not have to be 24; it simply must be different than the DSCP values used for audio and for video.)

• Use the previously-configured port range for video traffic. For example, if you have reserved ports 42000 through 42019 for application sharing, then set the port range to this: 42000:42019.

For a file transfer policy:

• Use a different (and unique) policy name (for example, Lync Server File Transfers).

• Set the DSCP value to 14. (Again, this value does not have to be 14; it simply must be a unique DSCP code.)

• Use the previously-configured port range for application. For example, if you have reserved ports 42020 through 42039 for application sharing, then set the port range to this: 42020:42039.

The new policies you have created will not take effect until Group Policy has been refreshed on your client computers. Although Group Policy periodically refreshes on its own, you can force an immediate refresh by running the following command on each computer where Group Policy needs to be refreshed:

Gpudate.exe /force

This command can be run from any command window that is running under administrator credentials. To run a command window under administrator credentials, click Start, right-click Command Prompt, and then click Run as administrator.

Keep in mind that these policies should be targeted towards your client computers. They should not be applied to servers running Lync Server.

To help ensure that network packets are marked with the appropriate DSCP value, you should also create a new registry entry on each computer by completing the following procedure:

1. Click Start and then click Run.

2. In the Run dialog box, type regedit and then press ENTER.

3. In the Registry Editor, expand HKEY_LOCAL_MACHINE, expand SYSTEM, expand CurrentControlSet, expand services, and then expand Tcpip.

4. Right-click Tcpip, point to New, and then click Key. After the new registry key is created, type QoS and then press ENTER to rename the key.

5. Right-click QoS, point to New, and then click String Value. After the new registry value is created, type Do not use NLA and then press ENTER to rename the value.

6. Double-click Do not use NLA. In the Edit String dialog box, type 1 in the Value data box and then click OK.

7. Close the Registry Editor and then reboot your computer.