The situation is illustrated in Figure 3.5, in which Host C initiates two HTTP sessions to server B, and Host A initiates one HTTP session to B. Hosts A and C and server
B each have their own unique IP address—A, C, and B, respectively. Host C assigns
two different source port numbers (26145 and 7532) to its two HTTP connections.
Because Host A is choosing source port numbers independently of C, it might also
assign a source port of 26145 to its HTTP connection. But this is not a problem—server
B will still be able to correctly demultiplex the two connections having the same source
port number, since the two connections have different source IP addresses.