@ismasan @dcrossney Pub/Sub is orthogonal to issues of the message transport. There's nothing about Pub/Sub that either expects or dictates message durability. There's no "usually" wrt the Pub/Sub pattern. Particular implementations of a pattern may make specific decisions given the use case the implementation addresses, but I'll say with 110% confidence that the Pub/Sub pattern itself - due to the fact that it's a pattern - has nothing to say about any particular implementation.