The TCP/IP Suite of Protocols

Although they are frequently identified as just “TCP/IP,” several different component protocols actually exist within the IP suite of protocols. These include:

• IP—The Internet Layer protocol.
• TCP—The reliable Host-to-Host Layer protocol.
• UDP—The best-effort Host-to-Host Layer protocol.
• ICMP—A multilayer protocol designed to facilitate control, testing, and management functions within an IP network. The various ICMP protocols span the Host-to-Host Layer and the Process/Application Layer.