After seeing one failure of the TestJPPFUuid unit test (the only one I've seen in years), I performed some more rigorous testing of the uuids generated by JPPFUuid. I found that there is around 1 collision for every 40 million (40,000,000) uuids. Essentially, this is due to the use of a non cryptographically strong random number generator, namely java.util.Random. Instead, we should use java.security.SecureRandom.