Managers can update a new port group membership as many times as they want using this object. Setting this object to a new value does not change the current membership and the value will be resetted after a system crash. The new value is copied to portGroupMembership when portGroupAction is set to doUpdate and the updating process successfully changes the port member. A port group is expressed using a shorthand that says what bridge ports are members of the group. An examples of a specification is: (1,3,5) (32-36) (6,12-24,36) () A list of bridge ports between 1 and 36 are used to represent the members of the port group. A bridge port becoming a member of a port group ceases to operate as a normal bridge port, therefore filters on the port have no effect. If a port group is specified as an empty set, the members in the group will operate as normal bridge ports and take their original brige port numbers. Their original filters will also become effective. Commas separate items in a list of bridge ports. Hyphens are short-hand for specifying a range of numbers. Bridge port numbers are specified in decimal. A port group will read back in a form equivalent to the form written. It may not read back exactly as written. If the manager specifies a member that is overlapped with a member of a preexisting port group in the same object, setting portGroupAction to doUpdate will fail.