The participants in a discussion can be individuals, groups, or even members of another discussion.

The following types of subscribers are possible:

Account holders
Participants in a discussion are usually members of a CollabNet-supported domain. These subscribers can be identified from within the system with a user name alone.
Anonymous subscribers
People who do not have a CollabNet account (or account holders who want to remain anonymous) can subscribe to some discussions, if the project owner allows it. Anonymous subscribers use their full email address, such as

Note: Anonymous subscriptions must be verified before they are activated. The system sends a confirmation message to the subscriber's address, and the subscription is activated when a confirmation response email is received.

Group subscribers
A group of users can be subscribed to a discussion. Group subscribers are denoted by an email alias like this: <group>&<domain>. Notifications sent to a group subscriber are sent to all of the current members of the group.
Other discussions
You can subscribe a discussion as a participant in another discussion. When you do this, the participants in the subscribing discussion are notified by email that their discussion has been added to the other discussion.

Note:When you enrol a discussion as a subscriber, email messages are not sent to that discussion. Instead, only the subscribers to that discussion are added to the distribution list of the subscribed discussion and its users receive the messages.

Note: User groups and other discussions can be subscribed to a discussion only through the message-by-message or digest-only subscription modes. When a user group and or another discussion has been subscribed to a discussion, the members of the group or discussion will receive email notification regardless of the permission they hold.

Note: You must be the administrator of a discussion to add a discussion as a subscriber.