1. A method of transmitting packets in a computer network having a hierarchy of domains individually having one or more network nodes interconnected with one or more end points, the method comprising: at a first network node in a first domain of the hierarchy, receiving a plurality of packets with corresponding end point identifiers individually having a stack with a first section containing a value corresponding to a higher-level domain that is above the first domain in the hierarchy and a second section containing another value corresponding to a second domain, the higher-level domain being different from the second domain; determining a first network route from the first network node to the higher level domain by performing a comparison of the value of the first section of the end point identifiers with entries in a forwarding table in the first network node, one of the entries of the forwarding table specifying a network path from the first network node to the higher-level domain as a destination corresponding to all end points in the second domain; and forwarding the packets to a second network node in the higher-level domain based on the determined first network route; and at the second network node in the higher-level domain, removing the first section from the stack; determining a second network route from the second network node to the end points in the second domain based on the another value in the second section of the end point identifiers; and forwarding the packets from the second network node to the end points in the second domain based on the determined second network route.