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A Term Paper On Subject Network & Telecommunication In Partial Requirement for the Program RD MBA (EB) 3 - SEM. (2010-11) Submitted To Submitted By Mr. Ashish Sonker Rajesh Kumar Roll No. – 35 Department Of Business Administration University Of Lucknow ACKNOWLEDGEMENT Every task constitutes great deal of assistance and guidance from the people concerned and this particular term paper is of no exception a project of this nature surely a result of tremendous support, guidance, encouragement and help. I express my sense of gratitude to Mr. Ashish Sonker, faculty member of department of Business Administration, University of Lucknow. I thank him for his constructive help, constant support in completing this term paper. I would also like to thank my friends and all those individuals who gave me the proper references and provided me with relevant information on this topic, gave me important web links for assistance & helped me a lot. Finally I thank my parents & great GOD with my deepest gratitude. Rajesh Kumar Ethernet Ethernet is a family of frame-based computer networking technologies for local area networks (LANs). The name comes from the physical concept of the ether. It defines a number of wiring and signaling standards for the Physical Layer of the OSI networking model, through means of network access at the Media Access Control protocol (a sub-layer of Data Link Layer), and a common addressing format. Ethernet is standardized as IEEE 802.3. The combination of the twisted pair versions of Ethernet for connecting end systems to the network, along with the fiber optic versions for site backbones, is the most widespread wired LAN technology. It has been in use from around 1980[1] to the present, largely replacing competing LAN standards such as token ring, FDDI, and ARCNET. standard 8P8C (often called RJ45) connector used most commonly on cat5 cable, a type of cabling used primarily in Ethernet networks. History Ethernet was developed at Xerox PARC between 1973 and 1975. In 1975, Xerox filed a patent application listing Robert Metcalfe, David Boggs, Chuck Thacker and Butler Lampson as inventors, U.S. Patent 4,063,220 "Multipoint data communication system (with collision detection)". In 1976, after the system was deployed at PARC, Metcalfe and Boggs published a seminal paper. The experimental Ethernet described in the 1976 paper ran at 3,000,000 bits per second (3 Mbit/s) and had eight-bit destination and source address fields, so the original Ethernet addresses were not the MAC addresses they are today. By software convention, the 16 bits after the destination and source address fields specified a "packet type", but, as the paper says, "different protocols use disjoint sets of packet types". Thus the original packet types could vary within each different protocol, rather than the packet type in the current Ethernet standard which specifies the protocol being used. Metcalfe left Xerox in 1979 to promote the use of personal computers and local area networks (LANs), forming 3Com. He convinced DEC, Intel, and Xerox to work together to promote Ethernet as a standard, the so-called "DIX" standard, for "Digital/Intel/Xerox"; it specified the 10 megabits/second Ethernet, with 48-bit destination and source addresses and a global 16-bit type field. The first standard draft was first published on September 30, 1980 by the Institute of Electrical and Electronics Engineers (IEEE). It competed with two largely proprietary systems, Token Ring and Token Bus. To get over delays of the finalization of the Ethernet "Carrier sense multiple access with collision detection" (CSMA/CD) standard due to the difficult decision processes in the "open" IEEE, and due to the competitive Token Ring proposal strongly supported by IBM, support of CSMA/CD in other standardization bodies (i.e. ECMA, IEC and ISO) was instrumental to its success. The proprietary systems soon found themselves buried under a tidal wave of Ethernet products. In the process, 3Com became a major company. 3COM built the first 10 Mbit/s Ethernet adapter (1981). This was followed quickly by DEC's Unibus to Ethernet adapter, which DEC sold and used internally to build its own corporate network, reaching over 10,000 nodes by 1986, far and away the largest then extant computer network in the world. The advantage of CSMA/CD was that, unlike Token Ring and Token Bus, all nodes could "see" each other directly. All "talkers" shared the same medium - a single coaxial cable - however, this was also a limitation; with only one speaker at a time, packets had to be of a minimum size to guarantee that the leading edge of the propagating wave of the message got to all parts of the medium before the transmitter could stop transmitting, thus guaranteeing that collisions (two or more packets initiated within a window of time which forced them to overlap) would be discovered. Minimum packet size and the physical medium's total length were thus closely linked. Through the first half of the 1980s, Digital's ethernet implementation utilized a coaxial cable about the diameter of a US nickel (5¢ coin) which became known as "thick wire ethernet" when its successor, "thin wire ethernet" was introduced. Thin-wire ethernet was in essence a high-quality version of the cable used on closed-circuit television of the era. The emphasis was on making the physical routing of cable easier, less costly, and, whenever possible, utilize existing wiring. The observation that there was plenty of excess capacity in unused "twisted pair" (sometimes "twisted copper") telephone wiring already installed in commercial buildings provided another opportunity to expand the installed base and thus twisted-pair ethernet was the next logical development. Twisted-pair Ethernet systems were developed in the mid 1980s, beginning with StarLAN, and become widely known with 10BASE-T. These systems replaced the coaxial cable on which early Ethernets were deployed with a system of hubs linked with unshielded twisted pair (UTP), ultimately replacing the CSMA/CD scheme in favor of a switched full duplex system offering higher performance. Standardization Notwithstanding its technical merits, timely standardization was instrumental to the success of Ethernet. It required well-coordinated and partly competitive activities in several standardization bodies such as the IEEE, ECMA, IEC, and finally ISO. In February 1980 IEEE started a project, IEEE 802 for the standardization of Local Area Networks (LAN). The "DIX-group" with Gary Robinson (DEC), Phil Arst (Intel) and Bob Printis (Xerox) submitted the so-called "Blue Book" CSMA/CD specification as a candidate for the LAN specification. Since IEEE membership is open to all professionals including students, the group received countless comments on this brand-new technology. In addition to CSMA/CD, Token Ring (supported by IBM) and Token Bus (selected and henceforward supported by General Motors) were also considered as candidates for a LAN standard. Due to the goal of IEEE 802 to forward only one standard and due to the strong company support for all three designs, the necessary agreement on a LAN standard was significantly delayed. In the Ethernet camp, it put at risk the market introduction of the Xerox Star workstation and 3Com's Ethernet LAN products. With such business implications in mind, David Liddle (General Manager, Xerox Office Systems) and Metcalfe (3Com) strongly supported a proposal of Fritz Röscheisen (Siemens Private Networks) for an alliance in the emerging office communication market, including Siemens' support for the international standardization of Ethernet (April 10, 1981). Ingrid Fromm, Siemens representative to IEEE 802 quickly achieved broader support for Ethernet beyond IEEE by the establishment of a competing Task Group "Local Networks" within the European standards body ECMA TC24. As early as March 1982 ECMA TC24 with its corporate members reached agreement on a standard for CSMA/CD based on the IEEE 802 draft. The speedy action taken by ECMA decisively contributed to the conciliation of opinions within IEEE and approval of IEEE 802.3 CSMA/CD by the end of 1982. Approval of Ethernet on the international level was achieved by a similar, cross-partisan action with Fromm as liaison officer working to integrate IEC TC83 and ISO TC97SC6, and the ISO/IEEE 802/3 standard was approved in 1984. General description This is a Figure of 1990s network interface card. This is a combination card that supports both coaxial-based using a 10BASE2 (BNC connector, left) and twisted pair-based 10BASE-T, using an RJ45 (8P8C modular connector, right). Ethernet was originally based on the idea of computers communicating over a shared coaxial cable acting as a broadcast transmission medium. The methods used show some similarities to radio systems, although there are fundamental differences, such as the fact that it is much easier to detect collisions in a cable broadcast system than a radio broadcast. The common cable providing the communication channel was likened to the ether and it was from this reference that the name "Ethernet" was derived. From this early and comparatively simple concept, Ethernet evolved into the complex networking technology that today underlies most LANs. The coaxial cable was replaced with point-to-point links connected by Ethernet hubs and/or switches to reduce installation costs, increase reliability, and enable point-to-point management and troubleshooting. StarLAN was the first step in the evolution of Ethernet from a coaxial cable bus to a hub-managed, twisted-pair network. The advent of twisted-pair wiring dramatically lowered installation costs relative to competing technologies, including the older Ethernet technologies. Above the physical layer, Ethernet stations communicate by sending each other data packets, blocks of data that are individually sent and delivered. As with other IEEE 802 LANs, each Ethernet station is given a single 48-bit MAC address, which is used to specify both the destination and the source of each data packet.