We present a new network-layer architecture that provides generalized addressing. The forwarding infrastructure is independent of the addressing architecture, so multiple addressing architectures can be used simultaneously. We compare our solution with the existing Internet protocols for unicast and multicast services, given the address assignment used in the Internet. By means of an extensive simulation study, we determine the range of parameters for which the overhead costs (delay, state, and network load) of our service are comparable to those of the Internet.