Multicast Network Diagnostics

A Shortest Path Bridging (SPB) network provides a multicast traceroute using network identifiers such as IP addresses for the source and destination (multicast group). The network identifiers, which are based on layer 3 (IP) designations of the traced multicast group, are mapped to a network identifier of the multicast group (corresponding to a layer 2, or MAC address) and an associated Virtual Local Area Network (VLAN) which is used to transport the packets belonging to the multicast flow. Therefore, an operator issuing the traceroute command need not be familiar with the layer 2 concepts of the network, but rather need only supply the layer 3 (IP address) designations of the concerned entities. 15