TCP/IP Protocol Suite
While the Internet today is acknowledged as a network that is fundamentally shifting social, political, and economic structures, and in many ways eliminating geographic boundaries, this potential is simply the realization of predictions that date back nearly fifty years. In a series of memos going back to August 1962, J.C.R. Licklider of MIT discussed his "Galactic Network" and how social interactions could be enabled by networking. The Internet surely supplies such a national and global infrastructure and, in fact, interplanetary Internet communication has already been seriously studied.
Prior to the 1960s, what little computer communication existed represented basic text and binary data, transmitted through the most standard telecommunications network technology of the day; namely, circuit switching, the technology of the telephone networks for almost a hundred years. Since most data traffic is bursty in nature, circuit switching results in extremely inefficient use of network resources.
The underlying technology that makes the Internet function is called packet switching, a data network in which all elements (i.e., hosts and switches) work independently, wiping out single point-of-failure problems. Additionally, network communication resources look to be dedicated to individual users but, in reality, statistical multiplexing and a maximum on the size of a transmitted entity result in accelerated, efficient networks.
The modern Internet started as a U.S. Department of Defense (DoD) funded experiment to interlink DoD-funded research locations in the U.S. The 1967 the first design for the so-called ARPANET — titled for the DoD's Advanced Research Projects Agency (ARPA) — was first released by Larry Roberts. In September 1969, the first client of the ARPANET was installed at the University of California at Los Angeles (UCLA), followed each month with nodes at Stanford Research Institute (SRI), the University of California at Santa Barbara (UCSB), and the University of Utah. With four nodes by the end of 1969, the ARPANET crossed the continental U.S. by 1971 and had connections to Europe by 1973.
The first host-to-host communications protocol introduced in the ARPANET at it's inception in 1969 was called the Network Control Protocol (NCP). Over time, however, NCP proved to be incapable of keeping up with the growing network traffic load. The next problem in the new ARPAnet was that there was no standardized means of transferring files over the network. A group of researchers assembled for six months and put together a File Transfer Protocol (FTP) that would determine the format of the data that would move over the ARPAnet. It was finished in July 1972. In 1973, development of a mature system of internetworking protocols for the ARPAnet began. What many don't realize is that in early variations of this technology, there was just one core protocol: TCP. And in fact, these letters did not even represent what they do today; they stood for the Transmission Control Program.
In 1974, a new, more robust set of communications protocols was planned and applied throughout the ARPANET, based on the Transmission Control Protocol (TCP) for end-to-end network communication. Only it seemed like overkill for the intermediate gateways (what we'd now call routers) to needlessly have to contend with an end-to-end protocol so in a discussion between Cerf, Postel and Dany Cohen at ISI in 1978, they chose to divide TCP in to two separate roles of TCP and the Internet Protocol (IP). In the book "Where Wizards Stay Up Late" the writers cite how the TCP would be in charge of the breaking apart the datagrams and messages and then reassembling them at the destination, and the IP would be responsible for sending the individual datagrams.
The original versions of both TCP and IP that are in general use today were scripted in September 1981, though both have had numerous modifications applied to them (additionally, the IP version 6, or IPv6, specification was released in December 1995). In 1983, the Department of Defense mandated that all of their computer systems would utilize the TCP/IP protocol suite for long-haul communications, further heightening the range and importance of the ARPANET and the TCP/IP protocol.
TCP/IP was once just “one of numerous” different sets of protocols that could be employed to supply network-layer and transport-layer functionality. Today there remain some other alternatives for internetworking protocol suites, but TCP/IP is the universally-accepted global standard. Its increase in popularity has been due to a number of significant factors. A few of these are historical, such as the fact that it is linked to the Internet as reported above, while others are concerned with the features of the protocol suite itself. Primary among these are the following:
Integrated Addressing System: TCP/IP includes inside it a system for discovering and directing devices on both small and large networks. The addressing system is organized to permit devices to be directed regardless of the lower-level details of how each component network is constructed. Over time, the mechanisms for addressing in TCP/IP have improved, to match the needs of maturing networks, particularly the Internet. The addressing system also has a centralized administration capability for the Internet, to ensure that each device holds a unique address.
Design For Routing: different than many network-layer protocols, TCP/IP is specifically configured to facilitate the routing of data across a web of absolute complexity. In truth, TCP/IP is conceptually interested more on the connection of networks, than with the connection of devices. TCP/IP routers enable data to be presented between devices on different networks by shifting it one step at a time from one network to the next. Several support protocols are also included in TCP/IP to permit routers to interchange vital information and manage the efficient stream of information from one network to another.
Underlying Network Independence: TCP/IP runs mainly at layers three and above, and includes provisions to permit it to run on just about any lower- layer technology, including LANs, wireless LANs and WANs of various kinds. This flexibility signifies that one can mix and match an assortment of different underlying networks and link them all using TCP/IP.
Scalability: among the most astonishing features of TCP/IP is how scalable its protocols have turned out to be. Over the decades it has demonstrated its spunk as the Internet has matured from a small network with only a couple of machines to a huge internetwork with millions of servers. While some modifications have been needed periodically to sustain this growth, these alterations have happened as part of the TCP/IP growth process, and the substance of TCP/IP is essentially the same as it was over twenty-five years ago.
Open Standards and Development Process: The TCP/IP standards are not copyrighted, but open standards freely accessible to the public. What is more, the method used to evolve TCP/IP standards is also entirely open. TCP/IP standards and protocols are developed and expanded using the unique, democratic “RFC” process, with all interested parties welcome to participate. This guarantees that anyone with an interest in the TCP/IP protocols is afforded a chance to supply input into their development, and likewise ensures the global acceptance of the protocol suite.
Universality: Everyone uses TCP/IP because everyone uses it! Not only is TCP/IP the “underlying language of the Internet”, it's also utilized in most nonpublic networks today. Even former “competitors” to TCP/IP such as NetWare today use TCP/IP to transmit traffic. The Internet continues to grow, as do the capabilities and uses of TCP/IP. It is probable that TCP/IP will remain a large piece of internetworking for the foreseeable future.
Key Concept: While TCP/IP isn't the only internetworking protocol suite, it is unquestionably the most significant one. Its unparallaled success flows from a variety of factors. These include its technical features, such as its routing-friendly design and scalability, its historical function as the protocol suite of the Internet, and its open standards and growth process, which bring down barriers to acceptance of TCP/IP protocols.
All of the information we run through our current Internet Providers is sent using the basic TCP/IP technology. TCP/IP, originally prompted by low-reliability wireless packet radio networks, has now become now the most dependable and widely deployed network worldwide, and the IPv4 version developed in the 1970's, in addition to the IP version 6, or IPv6, spec that was released in December 1995, remains the standard protocol used on the Internet today.