undestand discovery in JXTA
Hello to everybody! I'm new in JXTA, I'm studying a lot of documentation (i.e. "JXTA v2.0 Protocols Specification" and "JXTA Javaâ„¢ Standard Edition v2.5:") but I've still missed a couple of basic concepts.
1. How Shared Resource Distributed Index (SRDI) and DiscoveryProtocol are related? I've undestand that when a peer invoke, for instance, a getRemoteAdvertisement(null, DiscoveryService.PEER, attributeName, attributeValue, treshold), the query is propagated, via RDV peer, to edge peers. A TTL-based system is used to avoid network congestion. Are the DHT used in this scenario? Why advertisement indexes are stored and pushed by RDVs and how it is used in discovery?
2. I would like to work with Java SE binding but I've not properly understood the concept of QueryHandler. Am I forced to implement this interface or a "default" implementation is availabe in the reference implementation? What's the role of this class? The discovery still works if I don't implement the QueryHandler interface?
Thanks in advance for your help!