TCP/IP Port Filtering

TCP/IP port filtering is the practice of selectively enabling or disabling Transmission Control Protocol (TCP) ports and User Datagram Protocol (UDP) ports on computers or network devices. When used in conjunction with other security practices, such as deploying firewall software at your Internet access point, applying port filters to intranet and Internet servers insulates those servers from many TCP/IP-based security attacks, including internal attacks by malicious users.

An Internet or intranet host, such as a computer or network device on a TCP/IP-based network, uses a combination of an IP address and port number to communicate with an application or service running on another Internet or intranet host. Together, an IP ...

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