 null spanning tree instance. The application of Connection Admission Control (CAC) and a means of accounting for bandwidth assigned in the control/management plane. Data plane OAM provides both fault and performance management. As the actual frame transfer function across an Ethernet switch is unmodified (learned or configured), existing OAM can be largely reused. One change is that OAM uses the same MAC address as the user traffic. The delegation of a small portion of the VLAN identifier range to configured as opposed to learned behavior has a trivial impact on the scaling properties of VLAN partitioned bridg- ing yet simultaneously permits a large number of point-to-point or multipoint-to-point ESPs to be supported. Setting aside as few as 16 VLAN identifiers allows 16 uniquely routed multipoint-to-point multiplexed paths to each of the set of BEBs in the network, while allow- ing 4078 VLAN identifiers for bridged behavior. This gives a theoretical maximum of some 252 ESPs fully meshing (including resiliency) some 248 devices. It is obvious that the theoreti- cal limit outstrips the capacity of existing implementations. Unlike the case where flooding and learning are employed, the configured option only requires knowledge of peers on a need-to-know basis. Protection Mechanisms A configured ESP has complete route freedom (with the exception of corouting for bidirectional connections), and the ability to define multiple paths to any BEB combined with route freedom has a number of implications. When there are a number of paths between any two points in the network, a spanning tree with bridging and auto-learning allows only one of these to be used. This is in sharp contrast to configured behavior, which allows more than one path between any two points and permits criteria beyond simply the shortest path to be used in selecting the routing of any individual path. A wide variety of metrics can be used along with appropriate algorithms and offline computation to select optimal sets of paths with specific attributes 