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you serious about running your network to its maximum potential?
Then you need to replace your hub with a switch. Here are
few guidelines to follow when buying a switch. by Mahesh
main job of an Ethernet switch is to divide networks into
segments and providing each segment with dedicated bandwidth
a network grows and new users are added, the network's bandwidth
becomes more crowded and traffic slows down. For example,
if a network has 100 Mbps of bandwidth, and 4 users are using
the network heavily, each user will receive only 25 Mbps of
bandwidth (100 divided by 4). Because everyone on the network
is sharing the same space, this shared network can grind to
a halt during peak network activity.
This problem can be addressed by using a switch. Similar to
a hub, a switch transforms a shared network into a switched
network, giving all users access to the network's full bandwidth.
In the example above, all of the users would enjoy true 100
Mbps bandwidth instead of 20 Mbps. Since a switch helps users
make the most of a network's potential, most 10/100 network
looking for maximum performance should have one, especially
in areas of high traffic. Power-hungry workgroups requiring
maximum bandwidth should definitely be connected to a switch.
is a Switch?
in a LAN, all devices attached to the network share that network's
bandwidth. As more devices are attached to the network and
as bandwidth requirements expand, network congestion also
increases. The main job of an Ethernet switch is to divide
networks into segments and providing each segment with dedicated
bandwidth. The switch transfers traffic between network segments
to allow a station on one segment to address a station on
Like bridges, switches subdivide larger networks and prevent
the unnecessary flow of network traffic from one segment to
another, or in the case of cross-segment traffic, switches
direct the frames only across segments containing the source
and destination hosts.
Do Ethernet Switches Work?
Ethernet switches mainly work at the Layer 2 (Data Link
Layer) of the OSI model. They check the destination media
access control (MAC) address on each incoming frame, and look
up the address in their tables to find out whether it is local
to that port or is destined for another port. If the address
is not local, they switch the frame to its appropriate destination
different are switches?
Switches themselves are hardware devices that look similar
to routers, hubs or bridges. However, three important factors
separate switches from their networking cousins: overall speed
(switches are much faster); forwarding methodology or electronic
logic (smarter); and higher port counts. In contrast to the
functionality of bridges and routers, which traditionally
utilize the less effective and more expensive microprocessor
and software methods, switches direct data frames across the
various segments in a faster and more efficient manner through
an extensive reliance upon on-board logic, through Application-Specific
Integrated Circuits (ASICs).
to buy a switch?
A switch isn't necessary for every network. A decision
to buy a switch is influenced by two factors: to improve network
performance and to run high-speed bandwidth heavy applications
enhance performance: A switch will improve performance
for any file servers or workstations connected directly to
it. Small network can use a switch instead of a hub to give
workstations maximum speed. If a network is large, it should
have at least one switch in every high-traffic workgroup.
As a general rule, try to get every file server, critical
workstations, and print server connected directly to a switch.
run high-speed applications: When a network will be using
high-speed applications like multimedia or video generally
speaking, every workstation and file server that will be using
multimedia or video should be connected to a switch to avoid
Anywhere a 10/100 Fast Ethernet hub is required small workgroups
and large network alike will benefit more from using a 10/100
switch to maximize performance over a mere 10/100 hub alone.
Switches can be classified according to the way they forward
data packets or the manner in which they handle network traffic.
and Forward switches
Store-and-forward switches, take an entirely different
approach. Instead of the faster send-it-as-soon-as-you-can
rule used by cut-through devices, store-and-forward devices
wait until the entire packet is received by the switch, only
then sending it on to its destination.
Dynamic switches not only forward packets to their proper
destination, but also maintain a table that associates individual
nodes with the specific ports to which they are connected.
This information is updated each time a particular machine
transmits data across the network, allows the switch to quickly
direct frames across the proper segments, rather than across
all segments on the switch.
Segment switches can handle the traffic from an entire
network segment on each port, allowing you to connect a higher
number of workstations or segments with fewer switches/physical
ports. The aspect behind segment switches is that they are
also capable of handling a single workstation on each port
(in essence, a segment with one node).
Port switches are designed to accommodate a single device
on each physical port. However, implementing a port-switching
solution demands a good deal of capital for additional wiring
(cable runs are needed from each device directly to the switch)
and enough switches to provide the requisite number of physical
to look for in a switch
16 or 24-Ports switches should run at 10/100 Full Duplex
and have an auto sensing capability
Should be perfect for running 10BaseT, 100BaseTX and 100BaseFX
Data flow control should be able to filter out faulty data
Must be capable of advanced store-and-forward data packet
Rathod can be reached at email@example.com