What is used to identify a specific process to which an internet or other network message is forwarded when it arrives at a server?

What is used to identify a specific process to which an internet or other network message is forwarded when it arrives at a server?

• A. IP Address
• B. MAC Address
• C. Port Number
• D. Domain Name

Answer: (C)

Port numbers serve as the doorway to the right application on a server. When a packet arrives, the server uses the IP address to reach the correct machine, then uses the destination port to deliver the data to the specific process listening on that port. This IP address plus port combination forms the socket that ties the connection to a particular application, such as a web server listening on port 80 or 443. MAC addresses are for local hardware addressing on a network segment and don’t determine which process handles the data once it’s at the host. Domain names are human-friendly aliases that get resolved to an IP address to locate the server, but they don’t select the internal receiving process.

Port numbers serve as the doorway to the right application on a server. When a packet arrives, the server uses the IP address to reach the correct machine, then uses the destination port to deliver the data to the specific process listening on that port. This IP address plus port combination forms the socket that ties the connection to a particular application, such as a web server listening on port 80 or 443. MAC addresses are for local hardware addressing on a network segment and don’t determine which process handles the data once it’s at the host. Domain names are human-friendly aliases that get resolved to an IP address to locate the server, but they don’t select the internal receiving process.