The Internet protocols comprise the most popular, nonproprietary data-networking
protocol suite in the world. The Internet protocols are communication protocols
used by electronic devices to talk to each other. Initially, computers were the
primary clients of IP protocols, but other types of electronic devices can connect
to IP networks, including printers, cellular phones, and MP3 players.
Today, even common devices such as vending machines, dishwashers, and cars
are being connected to IP networks.
The two best-known Internet protocols are Transmission Control Protocol
(TCP) and Internet Protocol (IP). The Defense Advanced Research Projects
Agency (DARPA) developed the Internet protocols in the mid-1970s. DARPA
funded Stanford University and Bolt, Beranek, and Newman (BBN) to develop
a set of protocols that would allow different types of computers at various
research locations to communicate over a common packet-switched network.
The result of this research produced the Internet protocol suite, which was
later distributed for free with the Berkeley Software Distribution (BSD) UNIX
operating system.
From there, IP became the primary networking protocol, serving as the basis
for the World Wide Web (WWW) and the Internet in general. Internet protocols
are discussed and adopted in the public domain. Technical bulletins called
Requests for Comments (RFC) documents proposed protocols and practices.
These documents are reviewed, edited, published, and analyzed, and then are
accepted by the Internet community (this process takes years).
The Internet protocol suite also comprises application-based protocols, including
definitions for the following:
• Electronic mail (Simple Mail Transfer Protocol [SMTP])
• Terminal emulation (Telnet)
• File transfer (File Transfer Protocol [FTP])
• HTTP
IP is considered a Layer 3 protocol according to the OSI model, and TCP is a
Layer 4 protocol.