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The LAN switchDate: 2015-10-07; view: 396. Read the text. Make summary of parts 10, 11 and 12 of the text. 1A LAN switch is a local area networking device that prevents data packet collision, and maximizes transmission speed as well as bandwidth allocation. This is a good replacement to a network hub and solves problems associated with expanding networks. 2LAN, as you know, is the geographically limited network; it is usually limited to a single office, home, department, or building. In some cases, though, a LAN can exist between neighboring buildings. 3It is comprised of various nodes ─ these are usually desktop computers and computer servers ─ that are physically connected through LAN cables or through a wireless router and are able to communicate with each other and share common resources (e.g. office printers). 4There are many ways of connecting the various nodes in a Local Area Network. Simple networks usually have nodes that are arranged in a bus (straight backbone with segments where nodes are attached) or ring topology (nodes are distributed on a circular backbone and only the node with the ring token can transmit or send data). 5They can also be arranged in a star-like arrangement where all nodes have an individual segment connecting them to a hub. The hub is a passive network device; it is simply a place where data packets pass from one node to all the other nodes connected to it (except the port from which the data originally came from). Complex networks are usually a combination of the bus and star typology. Backbones connect multiple hubs. 6All these networks have different physical properties (they vary in the way a node can send and receive data to another node), but all these suffer from inefficient bandwidth usage, extremely low speeds and data collision incidence. 7In a network where a LAN switch is used, each node gets a direct connection to a switch. That is, a node gets a dedicated connection to the switch which only it (the node or the computer) and the switch use. This dedicated connection makes it possible for one node to maximize use of the bandwidth available to it. After all, no other node is competing with it for bandwidth. This means speedy data transmission. 8Moreover, the connection between the node and the switch can be made using cabling which has a separate route for data that the node is sending out and a separate route for data that the switch is forwarding to the node. This eliminates problems of data collision. 9The LAN switch is especially a vast improvement over the network hub since it has the ability to “read” the source and destination node of a data packet and forward the packet only to the destination node. 10Whenever the node transmits data meant for another node in the local area network, the switch intercepts the data, determines the destination and forwards the transmission to its intended destination. Since a data packet does not get broadcasted to unnecessary segments, network congestion is minimized and network bandwidth is conserved. (By Bradley Mitchell) |