Connection shutdown

A shutdown is a graceful closure of a connection. Each side wants to maximize the chances that outstanding requests complete successfully.

Shutdown steps

A client or a server follows these steps when it wants to shutdown an ice connection:

1. Stop sending new requests to the peer, and stop accepting new requests from the peer.

2. Wait for all (local) invocations and dispatches to complete.

3. Stop sending heartbeats to the peer.

4. Send a CloseConnection frame to the peer.
   The client or server skips this step if it already received a CloseConnection frame from the peer.

5. Wait for a CloseConnection frame from the peer or for the peer to close the duplex connection.
   This indicates the peer has completed all processing and it's safe to proceed to step 6.

6. Close the duplex connection.

The following sequence diagram shows the interactions between the client and server on connection shutdown:

CloseConnection frame

The CloseConnection frame is an ice protocol frame with type CloseConnection. Its body is empty. A client or server must not send any additional frame after sending a CloseConnection frame.