network-awareness


Jini-services and thus jAugment-services are network-aware. They are discovered, represented and used automatically as they become available and are no longer when they disapear. (Either because they were stopped or because they are no longer reachable.) This is handled be JINI-mechanisms called discovery and leases.
Services and UIs(service-browsers) need to belong to at least one common group to see each other. With such groups it is possible to make services available to only a part of the network.
They discover each other using broadcasts that are not routed outside the local network and ServiceLoccators(IP-adresses) to explicitely name a computer in another network.
The representations of services can run on different computers and even multiple representations can run for one service. Services, UIs and representations communicate with each other using messages. They register at each other to recive a numer of different message-types and are granted that right for a specified time until they either renew this contract or time out. This timeout is used everywhere remote ressources are used as a guard against particial network-failures. Othervise it would be possible for such registrations to accumulate and be stored for an infinite time while the receiver for the messages in no longer reachable.