This Service is invoked to delete one or more Subscriptions that belong to the Client's Session.

Successful completion of this Service causes all MonitoredItems that use the Subscription to be deleted. If this is the last Subscription for the Session, then all Publish requests still queued for that Session are de-queued and shall be returned with Bad_NoSubscription.

Subscriptions that were transferred to another Session must be deleted by the Client that owns the Session.