Using Client Version Policy to Specify Supported and Restricted Versions

You can create client version policies to explicitly support or restrict client versions. When a supported client logs on or is invited to a session, the client version policy checks the SIP User Agent header to determine the client version. Depending on the version of the client, and the rules that you have configured, the client version policy does one of the following:

• Allows the client to log on to the pool (that is, the Allow option).
  
  
• Allows Lync 2010 clients to log on and receive updates from Windows Server Update Service or Microsoft Update (that is, the Allow and Upgrade option). This action is available only for Microsoft Lync 2010 (where User Agent is OC).
  
  
• Allows the client to log on and presents the user with a message that indicates the user can upgrade their client. The message comes with the URL that you specify, and the user can clickthat URL to go to the page represented (that is, the Allow with URL option) and upgrade their client.
  
  
• Prevents the client from logging on to the pool (that is, the Block option).
  
  
• Prevents Lync 2010 clients from logging on and allows the client to receive updates from Windows Server Update Service or Microsoft Update (that is, the Block and Upgrade option). This action is available only for Microsoft Lync 2010 (where User Agent is OC).
  
  
• Prevents the client from logging on and presents the user with a message that indicates the user is using a client that is not supported. The message comes with the URL that you specify, and the user can click that URL to go to the page represented (that is, the Block with URL option).
  
  

Each pool maintains a client version control list that you configure. This list contains rules that specify the client versions you want to filter and the appropriate action for each client version. The Client Version Check can act according to a specific client version number. It can also act according to a client version that is less than or equal to or greater than or equal to the version number that you specify. The Client Version Check also includes a configuration option that specifies the default action for clients that are not included in the client version control list.

When you configure the Client Version Check, you specify the way in which clients are handled during logon. The Client Version Check provides options for configuring the following:

• User Agent header.   This is the name of the agent for the client version.
  
  
• Identity.   This is the scope that the rule should be applied to. If multiple rules with different levels of scope are triggered, the scope with the lowest level of granularity is applied. For example, if a service level rules states that the client should be blocked, but a user level rule also states that the client should be allowed, the client will be allowed as a user level rule is the most granular.
  
  

  Note:
  Because anonymous users are not associated with a user, site, or service, anonymous users are affected by global-level policies only.

• Client version number.   This includes the major version number, the minor version number, the build number, and the number that corresponds to the updated release of the client. The number is presented in the following format: <major version>.<minor version>.<build number>.<update number>.
  
  
• Matching rules.   These specify the comparison operations to perform to identify the specific version or range of versions of the client to which the filtering action is to apply.
  
  
• Action to take based on client version.   Available values are Allow, Block, Allow with URL, Block with URL, Allow and Upgrade, and Block and Upgrade.
  
  
• Client download URL. This is used only for the Block with URL and Allow with URL options.
  
  

A default list of rules is installed when you install Lync Server 2010. To customize the set up rules for your deployment, you can edit an existing rule, or you can create a new rule. If you do not want to block earlier version of the client, you will need to modify this list.

Note:

The default list of rules automatically blocks earlier versions of Microsoft Office Communicator and Microsoft Office Communicator Phone Edition that try to connect to Lync Server 2010. If you would like to change this behavior, you can create a new rule to allow earlier clients to connect to the Lync Server 2010 server and then add this to the top of the list. Although you can also edit the default rules to allow earlier clients to connect, we do not recommend this approach.

Important:
The rules are listed in their order of precedence. For example, if you have a rule that allows Communicator clients with a version 1.5 or later to connect, followed by a rule blocking clients earlier than version 2.0, the first rule will match and thus takes precedence. As a result, Communicator 1.5 clients can connect.

Client version checks in the version control list act on specific criteria. However, you also need to configure a default rule to apply to clients that do not match any other client version rule, specifying one of the following: Allow, Block, or Block with URL.