What Survives The Handoff

A phone on an active HTTP/3 download leaves Wi-Fi for cellular. Its source IP and port both change, the server validates the new path, and the connection continues.

Select every statement that matches RFC 9000. More than one is correct.

The connection keeps using the same connection ID, which is what lets the server recognise it

Packets sent on the old path must not contribute to congestion control or RTT estimation for the new path

On confirming the peer's new address, the endpoint must reset its congestion controller and RTT estimator to initial values

Stream state and byte offsets carry over, so the transfer resumes rather than restarting

Flow control limits and the negotiated TLS keys carry over untouched

Congestion state carries over, since resetting it would waste the bandwidth estimate already earned