Applies to: Office 365 for enterprises, Live@edu
Topic last modified: 2010-09-08
The cloud-based service supports a special kind of distribution group called a dynamic distribution group. Unlike the static membership list of a regular distribution group, also known as a public group, the membership list for a dynamic distribution group is calculated every time a message is sent to the group. This calculation is based on filters and conditions you define when you create the group. When an email message is sent to a dynamic distribution group, it is delivered to all recipients in the organisation that match the filters and conditions you defined.
Suppose you are using the cloud-based service at a university. Student enrollment in the various academic departments changes every term, even in the middle of the term. You can populate the Department field on the student mailboxes, and then use dynamic distribution groups to filter the students based on their department. That way you don't have to manually add or remove students from the departmental distribution groups.
In addition, dynamic distribution groups are useful if you want to conceal the members of a distribution group, because the group membership is never displayed to senders, recipients or other users.
Dynamic distribution groups are also useful in a cross-premises environment when your organisation uses both the cloud-based service and on-premises Microsoft Exchange servers on which you have large distribution groups. Because dynamic distribution groups are expanded into individual recipients at the destination, only a single copy of the message is transmitted between the cloud-based service and the on-premises Exchange organisation. This helps reduce message traffic between the cloud-based service and the on-premises Exchange organization and speeds message delivery for large distribution groups.
You have two options: precanned filters that use the IncludedRecipients parameter and customised filters that use the RecipientFilter parameter. You can't use customised filters and precanned filters at the same time.
Both filtering methods are implemented by using Windows PowerShell. Dynamic distribution groups don't appear in the Web management interface.
Here's a quick description of the differences between the two methods.
|Filtering method||Filterable attributes||Filter operators|
Precanned filters that use the IncludedRecipients parameter
Limited to the following:
Customised filters that use the RecipientFilter parameter
Any available recipient attributes can be used.
Any available Windows PowerShell conditional operator can be used. Wildcards and partial matches are supported.