A connection endpoint has:
When a connection has been established,
or whene a connection has received some data,
set connection's read timer to 60s.
When connection's read timer's current time becomes 0,
close the connection endpoint.
[1] 致死的エラーでは、次のようにします。
To close the connection endpoint:
[3] 要求行を構文解析とは
CONNECT hoge HTTP/1.1
CONNECT mode
WS mode