Hi John,
Conversation ids are formatted as standard UUIDs (Universally Unique Identifiers). They contain 128 bits of data, enough to have about 3.4 × 1038 different values. Here's a decent description of how likely a repeat is:
the annual risk of a given person being hit by a meteorite is estimated to be one chance in 17 billion, which means the probability is about 0.00000000006 (6 × 10−11), equivalent to the odds of creating a few tens of trillions of UUIDs in a year and having one duplicate. In other words, only after generating 1 billion UUIDs every second for the next 100 years, the probability of creating just one duplicate would be about 50%.
All that to say: not super likely.
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Brian Dupuis
Genesys - Employees - Sr. Director, PureCloud UI
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