18.104.22.168 Inbound or Outbound Proxy to Server
The TCP connection is initiated by the inbound or outbound proxy. The server name and port to be used for setting up the TCP connection are extracted from the URL of the HTTP request as specified in section 22.214.171.124. Once the connection is established, the inbound proxy or outbound proxy and the server use this connection for transmission of all the PDUs of the PDU stream.
By using a TCP/IP connection between the inbound or outbound proxy and the server, implementations of this protocol obtain a full-duplex channel for an unlimited number of bytes that provides reliable, in-order, at-most-once delivery semantics.