Expand description
Several registrations for one device, one per flow (RFC 5626 §4.2).
The reason to register more than once is stated in §4.2: “a UA MUST send a REGISTER request to
each of the outbound proxies in the outbound-proxy-set”, so that a proxy going away does not
take the user’s reachability with it. That only works if the flows are genuinely independent,
which is a statement about this code rather than about the protocol: a set that reports one
Result for the whole batch cannot help but let one failure stand for all of them.
So there is no aggregate Result here. Flows::register returns an outcome per flow, and
the failure of one is a fact about that flow — recorded, backed off according to §4.5, and
retried on its own schedule.