How Ports Complete the Connection
So far you have learned that IP addresses are used to make sure that data gets delivered to the correct destination. However, since the IP address only identifies the computer network card, then how does the computer know what application the data it receives is intended for? For example, let's use the postal service as an example again. You can send letters simply to an address but without putting a person's name on the envelope; then when the letter gets delivered, who gets to open it?
Ports are the solution to this problem in the TCP/IP suite. In addition to an IP address, a port number is used to identify the source and the recipient of data transmitted using TCP/IP. However, IP doesn't have fields in its ...
Get Microsoft® Windows® XP Unleashed now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
