RFC 6455, "The WebSocket Protocol", December 2011

Note: This RFC has been updated by RFC 7936, RFC 8307, RFC 8441

Errata ID: 7608
Status: Reported
Type: Technical
Publication Format(s) : TEXT
Reported By: Esmond Pitt
Date Reported: 2023-08-19

Section 7.1.1 says:

The underlying TCP connection, in most normal cases, SHOULD be closed
   first by the server, so that it holds the TIME_WAIT state and not the
   client (as this would prevent it from re-opening the connection for 2
   maximum segment lifetimes (2MSL), while there is no corresponding
   server impact as a TIME_WAIT connection is immediately reopened upon
   a new SYN with a higher seq number).  

It should say:

The underlying TCP connection, in most normal cases, SHOULD be closed
   first by the server, so that the TIME_WAIT occurs at the
   client, not at the server.  

Notes:

1. There is no such thing as a 'TIME_WAIT connection'.
2. TCP connections are never reused.
3. It is better for the TIME_WAIT *port* states to accumulate at the clients rather than at the server, as this distributes them among the client base and avoids possible resource exhaustion at the server (NB *not* port exhaustion, as the server is only using one port).
4. The part about 'as this would prevent it [the client] from re-opening the connection' is only true if the client is using a fixed local port number, which never works anyway.
5. The part about ' a TIME_WAIT connection is immediately reopened upon
a new SYN with a higher seq number' is nonsense.

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