A mobile peer might not be able to act as a server due to its intrinsic limitations, even though the network does not restrict it in any way. Both networking models feature advantages and disadvantages. As each client is added, the central point weakens; its failure can destroy the whole network. A P2P network delivers a quite different scenario. Since every entity or peer in the network is an active participant, each peer contributes certain resources to the network, such as storage space and CPU cycles.
As more and more peers join the network, the network's capability increases. Hence, as the network grows, it strengthens. The P2P network is unavailable only when no peers are active. You pay the price for the advantages a P2P network offers, however. Therefore, the enforcement of security policies, backup policies, and so on proves complicated in a P2P network.
This transient nature can trigger performance concerns. Different protocols, different architectures, different implementations. That accurately describes current P2P solutions. Currently, developers use diverse methodologies and approaches to create P2P applications. To tackle this deficit, Sun developed Jxta. Jxta strives to provide a base P2P infrastructure over which other P2P applications can be built. This base consists of a set of protocols that are language independent, platform independent, and network agnostic that is, they do not assume anything about the underlying network.
These protocols address the bare necessities for building generic P2P applications. Designed to be simple with low overhead, the protocols target, to quote the Jxta vision statement, "every device with a digital heartbeat. Jxta currently defines six protocols, but not all Jxta peers are required to implement all six of them. The number of protocols that a peer implements depends on that peer's capabilities; conceivably, a peer could use just one protocol.
Peers can also extend or replace any protocol, depending on its particular requirements. It is important to note that Jxta protocols by themselves do not promise interoperability. The same is the case with Jxta. Just because two applications are built on top of Jxta doesn't mean that they can magically interoperate. Developers must design applications to be interoperable.
However, developers can use Jxta, which provides an interoperable base layer, to further reduce interoperability concerns. Undoubtedly, the first step towards providing a universal base protocol layer is to adopt a suitable representation that a majority of the platforms currently available can understand. XML is the ideal candidate for such a representation. View Full Term. By clicking sign up, you agree to receive emails from Techopedia and agree to our Terms of Use and Privacy Policy. JXTA is an open-source Java-based application development protocol set that facilitates peer-to-peer P2P communication for connected network devices, such as mobile phones, computers and servers.
JXTA is derived from the word juxtapose. By: Justin Stoltzfus Contributor, Reviewer. On rare occasions it is necessary to send out a strictly service related announcement.
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Users of the application may be providers or consumers of the service abstracted by the application; they often perform both roles. Users of the application come and go and therefore may not be available at any particular point in time. Each protocol is simple to implement and integrate into existing systems.
This set of protocols defines JXTA. Application developers and hardware providers may provide their own language bindings. New languages can evolve and provide their own bindings to the JXTA protocols, and new platforms can be developed that implement the JXTA protocols in entirely new ways.
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