TCP/IP Protocol Suite
The Internet Protocol (IP) had nothing in common with the current Internet when it was first introduced. According to White (2010), “The TCP/IP protocol suite was created by a group of computer scientists in order to support a new type of network (the ARPANET) being installed across the United States in the 1960s and 70s” (p. 17). The experiment was successful and led to the wide acceptance of the new protocol. Currently, the whole Internet and the vast majority of the private networks use the TCP/IP protocol suite as the main data communication mechanism.
The first part of the abbreviation stands for the Transport Control Protocol, which is responsible for the guaranteed data delivery. As opposed to the TCP, UDP (User Datagram Protocol) does not verify the data accuracy on the receiving side. These two protocols constitute the main TCP/IP data communication suite. The network nodes operate over TCP whenever the guaranteed data delivery is required, while UDP is mostly used by secondary service functions. Some applications actually allow the user to choose the communication protocol. For example, the Network File System (NFS) could be mounted over UDP or TCP, based on the network reliability (Dean, 2009, p. 459). Other protocols in the TCP/IP suite are responsible for the network maintenance and internetworking routing. For instance, the reachability of the network host could be tested over ICMP (Internet Control Message Protocol) using the ping command.
The vast majority of all network operations are performed over TCP. Every network service is associated with the so-called TCP port, which is unique throughout the Internet. The email delivery systems use SMTP (Simple Mail Transport Protocol) over the TCP port 25 (Dean, 2009, p. 516). Another example is the web browsing, which occurs primarily over the TCP port 80. UDP also uses service ports for the communication purposes. For example, the UDP port 53 serves the DNS (Domain Name System) requests, responsible for the domain name translating into the plain IP address.