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LAN Switches

High speed LAN Switches - Keep you network traffic flowing smoothly.


Rush hour-all day, every day.
Applications such as document imaging, video/multimedia production, and intranet working are very demanding. They generate huge data files that often must be transferred between stations based on strict timing requirements. If such traffic is not transmitted efficiently, you end up with jerky video, on-screen graphics that take forever to refresh, or other irritating, debilitating problems.


These problems arise because in traditional LANs, only one network node transmits data at a time, while all other stations listen. This works in conventional, server-based LANs where multiple workstations share files or applications housed on a central server. But if a network has several servers, or if it supports high-bandwidth, peer- to-peer applications such as videoconferencing, the one-station-at-a-time model just won't work.


These vehicles clear the lanes.
While bridges and routers process data packets on an individual, first-come first-served basis, switches maintain multiple, simultaneous data conversions among attached LAN segments.


From the perspective of an end-user work-station, a switched circuit would appear to be a dedicated connection-a direct, full-speed LAN link to an attached server or other remote LAN node. Although this technique is somewhat different than what a LAN bridge or router does, switching hubs are based on similar technologies.


Which route will you choose?
Switching hubs that use bridging technologies are called Layer-2 switches-a reference to Layer 2 or the Data-Link Layer of the OSI model. These switches operate using the MAC addresses in Layer 2 and are transparent to network protocols. Switches that use routing technologies are
known as Layer-3 switches, referring to Layer 3- the Network Layer-of the OSI model. These switches, like routers, represent the next higher level of intelligence in the hardware hierarchy. (For more information on the OSI model, see Routers & Bridges.)


Layer-2 switches connect different parts of the same network, as determined by the network number contained with the data packet. Layer-3 switches connect LANs or LAN segments with different network numbers.


If you're subdividing an existing LAN, obviously you're dealing with only one network and one network number, so you can install a Layer-2 switch wherever it will segment network traffic the best, and you don't have to reconfigure the LAN. However, if you use a Layer-3 switch, you'll have to reconfigure the segments to ensure that each has a different network number.


Similarly, if you're connecting existing networks, you have to examine the currently configured network numbers before adding a switch. If the network numbers are the same, you need to use a Layer-2 switch. If they're different, you must use a Layer-3 switch.


Need Help?
If you need advice in setting up your network, call Tech Support on +32.2.749.99.55 or mail to techsupport@blackbox.be. Our experts will be glad to help you choose the right equipment.