Common LAN Architectures
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Common LAN Architectures, by the term we want to state the overall design of a LAN, included in the LAN architecture is the media access method and the physical components. |
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The three most common LAN architectures are Ethernet, Token ring and Arcnet. |
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Ethernet |
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Ethernet, the basis for the institute of Electrical and Electronic Engineers Inc(IEEE) standard 802.3, coas developed by Xerox, Digital Equipment Corporation , and Intel Ethernet network topologies are most commonly distinguished by the cable used. |
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The three cabling possibilities are Twisted pair, Thinnet and Thicknet. |
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Token Ring |
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A token ring network is an implementation of IEEE standard 802.5, the standard for token ring LAN’s. |
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The token passing access method, more than the physical cable layout, distinguishes token ring networks from other networks. |
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ArcNet |
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The Attached Resource Computer network (ArcNet) loosely maps to IEEE’s standard 802.4. |
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This specifies the standards for token passing bus networks using broadband cable. |
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ArcNet, however is a baseband network and can have a star or bus topology. |
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Ethernet |
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Originally known as Alto Aloha Network, Ethernet is a widely used local-area network (LAN) protocol originally created by Xerox PARC in 1973 by Robert Metcalfe and others (U.S. Patent # 4,063,220). |
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Being the first network to provide Carrier Sense Multiple Access / Collision Detection (CSMA/CD), Ethernet is a fast and reliable network solution that is still widely used today. |
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Below is a listing of different standards of Ethernet and additional information about each of them. |
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Ethernet II / DIX / 802.3 |
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Ethernet II is a revised version of Ethernet rewritten by with Digital Equipment Corp, Intel and Xerox. Ethernet II, also known as DIX, (Digital, Intel, and Xerox) and 802.3. |
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Fast Ethernet / 100BASE-T / 802.3u |
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Fast Ethernet is also referred to as 100BASE-T or 802.3u and is a communications protocol that enables computers on a local-area network to share information with one another at rates of 100 million bits per second instead of the standard 10 million BPS. |
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Fast Ethernet works over Category 5 twisted-pair wiring. |
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There are two available types of 100BASE-T standards. |
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The first standard known as 100BASE-T utilizes CSMA/CD. |
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The second standard, known as 100VG-AnyLAN or 802.12, is similar to the other standard; however, it utilizes a different type of Ethernet frame to send its data. |
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100BASE-T is available in three different types of cable technologies: |
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1. 100BASE-T4 = |
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Utilizes four pairs of telephone-grade twisted-pair wire and is used for networks that need a low-quality twisted-pair on a 100-Mbps Ethernet. |
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2. 100BASE-TX = |
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Developed by ANSI 100BASE-TX is also known as 100BASE-X, 100BASE-TX uses two wire data grade twisted-pair wire |
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3. 100BASE-FX = |
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Developed by ANSI, 100BASE-FX utilizes 2 stands of fiber cable. |
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Ethernet SNAP |
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Ethernet SNAP is short for Ethernet SubNetwork Access Protocol and is a type of Ethernet protocol that enabled old and new protocols to be encapsulated in a Type 1 LLC. |
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Gigabit Ethernet / 1000BASE-T / 802.3z / 802.ab |
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Gigabit Ethernet is also known as 1000BASE-T or 802.3z / 802.3ab is a later Ethernet technology that utilizes all four copper wires in a Category 5 (Cat 5 & Cat 5e) capable of transferring 1 Gbps |
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10 Gigabit Ethernet / 802.3ae |
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10 Gigabit Ethernet is also known as 802.3ae is a new standard that supports 10.000 Gb/s. |
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1000BASE-CX |
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A copper cable gigabit Ethernet standard that is no longer used. This standard has been replaced by 1000BASE-T. |
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1000BASE-LX |
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A fiber optic gigabit Ethernet standard that operates over single-mode fiber. |
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1000BASE-SX |
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A fiber optic gigabit Ethernet standard that operates over multi-mode fiber, with typical distances of up to 550 meters (1804 feet) |
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Ethernet adapter |
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Ethernet adapter is a term used to describe an Ethernet network card used to connect a desktop computer to a network. If you are looking for network adapter |
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Ethernet: Thinnet (9 Base 2) |
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This topology is called Thinnet 9 Base 2. |
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The nickname derives from the size of the cable, which is roughly the size of a garden hose and too stiff to band with your hands. |
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A thin coaxial cable can transmit upto 9 Mbps roughly 200 meters over a baseband wire. |
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Thinnet networks generally use a local bus topology. |
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The cable used for this type of network is relatively inexpensive, and easy to install and configure. |
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As a result, this network is an economical way to support a small department or workgroup. |
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Ethernet: Thicknet (9 Base 5) |
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The main specification of the Ethernet topology commonly known as Thicknet 9 Base 5 are 9 Mbps, baseband and 500 meter segments. |
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Thicknet network generally use a bus topology. Thicknet was designed to support a backbone for a large department, or even an entire building. |
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Ethernet: Twisted-pair (9 Base T) |
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Twisted-pair 9 Base T, (9 Mbps, baseband, over-twisted-pair cable), is an Ethernet LAN that uses unshielded twisted pair cable to connect stations. |
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Most networks of this type are configured in a star pattern but internally use a bus signaling system like other Ethernet configurations. |
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Token Ring |
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Data on a token ring network is transmitted at either 4 or 16 Mbps, depending on the cable. |
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Network computers are connected by shielded and unshielded twisted pair cable to a wiring concentrator. |
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Each computer can be up to 90 meters from the multistation access unit (MAU) using shielded wire, or 45 meters using unshielded wire. |
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ArcNet |
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ArcNet is an easy to install and inexpensive baseband network that can have a star or a bus topology. |
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It typically uses co-axial cable and includes both active and passive hubs. Each work station is connected by cable to a hub. |
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The maximum cable length is from 120 meters to 606 meters depending on the type of cable and hub used. |