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3. KBRTestApp

After developing your own application & overlay next you should play with the KBRTestApp. KBRTestApp is a Tier1 application that tests 3 operations:
  1. OneWayTest - Route an overlay message to a random key & measure one-way hop count & latency. When a message reaches the destination, receiver call a method in the sender to collect statistics (not over the network). A sequence number is attached to a message to prevent collecting statistics of duplicate ones. Intermediate nodes append their addresses to a message while it's being forwarded.
  2. RPCTest - Send RPC call to a random key, wait for response, & then measure one-way hop count & latency. RPC context is used to keep track of destination & whether a message should be considered for statistics.
  3. LookUpTest - Lookup a random key using RPC call & collect latency when response is received. Sends as an internal RPC (sendInternalRpcCall) between two tiers (from application to overlay) using LookupCall messages.Context is used to carry additional data.
One or more tests can be selected by configuring the omnet.ini file. For each test application keeps track of number of messages send, received, & lost. You can also configure either to lookup any random key (within a bound) or only the existing ones. It's possible to issue messages while the network is in init phase. Each message is issued after a delay derived from a truncnormal distribution with a given mean & std.

Next Step
Extend KBRTest to provide more functionality such as:
  • Modify your MyOverlay & use it as the overlay for KBRTestApp.
  • Track hop count for messages & verify different routing types in OverSim


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