A network port is a common way of referring to three different things. Network access points, such as a home router, are often called network ports. The second common meaning refers to the actual location where a network cable connects to an access point or computer. These physical ports provide users with access to local area networks and the Internet. The last common use for this type of port refers to the software system that allows computers to handle multiple network tasks at the same time. These ports divide network traffic into a number of individual sources so that information and services remain separate.
Wireless routers are often called network ports.
When users refer to a hardware network port, one of two things usually happens. A network access point, such as a router, switch, or modem, may be called a port. This is especially common when talking about wireless networks, where the term “wireless port” is used to refer to the router that the system connects to. The other common hardware network port is the actual network connection. In this case, the small rectangular hole where the ethernet cable connects to your computer, router, or modem is the port. This usage is a holdover from older computing terms such as serial port or communication port.
A common type of serial cable is the recommended standard 232 (RS-232) cable, often found in computers.
The end use of the network port is software-based, not hardware-based. By this definition, a port is a software-based, non-physical location inside your computer. These ports divide network traffic and network-based services into segments. The computer can individually prioritize and process these threads, just as it does internal processes.
By splitting network sources, a computer can send and receive from multiple sources at the same time. Each active network port is capable of receiving information directly. For example, if a process was running on port 1000, that particular network port could send and receive information. Outgoing information would reference port 1000 as the sender and information returned would go specifically to port 1000. If a computer had a hundred different ports, they would all be doing the same thing.
In this situation, a network port follows certain guidelines on all computers. The port can be any number from zero to 65535, but many of the ports below 1024 are required for Internet-specific tasks. Processes such as web browsing, email, and telnet have predefined ports where the computer constantly monitors activity. Other programs, such as video games or software downloads, have ports defined by the user or the program that the computer only activates when the program is running.