For each forest in which you want to use Microsoft Office Communications Server 2007 R2, you need to specify the Session Initiation Protocol (SIP) domains that you have set up for Office Communications Server 2007 R2 and specify one SIP domain to be used as the default routing domain. If your topology and requirements change, you can add new domains or remove existing domains, as well as change the default routing domain.

Domains are individually enabled for SIP. Therefore, if you have multiple domains in your organization, you can enable one domain for SIP while not enabling SIP for the other domains. By enabling individual domains for SIP, you can also apply Group Policy according to the domain. By applying Group Policy per SIP domain, the users of one domain can have access to a different set of Office Communications Server 2007 R2 features than the users of another SIP domain.

Use the following procedures to add or remove a SIP domain or change the default routing domain.

To add or remove a SIP domain

  1. Open the Office Communications Server 2007 R2 snap-in.

  2. In the console tree, right-click the forest node, click Properties, and then click Global Properties.

  3. On the Generaltab, do one of the following:

    • To add a SIP domain, click Add. In the Add Domain Entrydialog box, type the fully qualified domain name (FQDN) of the SIP domain, and then click OK.

    • To remove a SIP domain, click the SIP domain, and then click Remove.

To specify the default routing domain

  1. Open the Office Communications Server 2007 R2 snap-in.

  2. In the console tree, right-click the forest node, click Properties, and then click Global Properties.

  3. On the Generaltab, do one of the following:

    • If the domain to be used as the default routing domain is in the list, skip to step 4.

    • If the domain to be used is not in the list, click Add. In the Add Domain Entrydialog box, type the name of the SIP domain, and then click OK.

  4. On the Generaltab, select the check box of the domain to be used as the default routing domain.