Jini vs. JXTA

From Jini.org

JXTA is a set of open protocols to enable Peer-To-Peer(P2P) communication, moreover JXTA effectively abstracts the network. Jini, on the other hand is a federation of distributed sofware components, which sometimes do communicate in a P2P fashion (and sometimes do NOT).

To the casual observer, both have some overlapping functions, but this is not actually the case. For example, both Jini and JXTA have lookup facilities but in Jini one is looking for an Java Interface (think of this as looking up for a function, a service) while in JXTA one looks for a peer by some name or inside a group. The JXTA type of lookup is more like trying to find an IP based on a name using a DNS, since JXTA abstracts the network this is a more than required functionality.

So JXTA connects the peers by allowing them to find each other and providing communications channels called pipes, all this is done with a protocol based on XML messages and it can cross firewalls easily. Over these pipes one can communicate using the protocol one desires, and peers can be running any programing language in any platform.

In conclusion JXTA is a powerful communication tool, and is very useful in that it allows crossing of firewalls. Finally Jini, as well as any other thing you can imagine, can make use of this power to create its distributed federation of software components.