Question

Suppose that a Web server runs in Host C on port 80. Suppose this Web server uses persistent connections, and is currently receiving requests from two different Hosts, A and B. Are all of the requests being sent through the same socket at Host C? If they are being passed through different sockets, do both of the sockets have port 80? Discuss and explain.

Answer 1

For each of persistent connections, Web server create the separate “connection sockets”. Each of the connection sockets is identified with the four-tuples:

• The source IP(Internet Protocol) addresses, source port numbers, destination IP(Internet Protocol) addresses, and the destinations port numbers.
• When the host C will received and the Internet Protocol datagrams then, it will examines these fields in the segments to determines by which the socket, it should be passed the payload of the Transmission Control Protocol segments.
• Thus, the request from the Host A and the HostB will be passed through the different sockets and the identifiers for both of the sockets has the port 80 for the destination ports.
• However, an identifier for the sockets have the different values for the sources of Internet Protocol addresses. Unlike the User Datagram Protocol, when the transport layers will passes the TCP segments payloads to the application processes and they does not specifies a sources of the Internet Protocol address, this is the implicitly specify by the sockets identifier.