A network routes update messages containing updates to properties of live objects
from input sources to clients having the objects. When the clients receive live
objects, the clients identify the object IDs associated with the objects and register
the object IDs with the routing network. The routing network is adapted to selectively
send update messages to nodes in the network and the nodes forward the messages
to the clients. One implementation uses a hierarchy of registries to indicate which
nodes and clients receive which update messages. Another implementation assigns
update messages to one or more of N categories and nodes to one or more of M types,
and the gateways maintain mapping between categories and types. To ensure that
clients receive all of the update messages for which they register, the clients
connect to client proxies that in turn connect to at least one node of each type.