How to process WIS2 Notification Messages with an "old" pubtime

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Question raised at the Global Services performance testing meeting in Japan: What should Global Brokers do with WIS2 Notification Messages that have an "old" pubtime?

1. What do we mean by "old" (i.e., how old is old)? With respect to Core data in a Global Cache, data only has a 24-hour shelf-life. But WNMs published in the last minute or so could well be circulating through the system?
2. If a WNM is "old" should a Global Broker discard the message?

To be discussed.

Based on the decision, the Tech Regs need to be updated.

See also wis2-guide/issue#141