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you planning to network your PCs? Here are some buying tips
on one of the most crucial elements of a network: the hub
hubs allow a network administrator to monitor and configure
them from a remote location
hub that supports the Simple Network Management Protocol allows
a network manager to configure the hub from anywhere on the
data communications, a hub is the pivot of convergence where
data arrives from one or more directions and is forwarded
to in one or more directions. A hub usually includes a switch
(in telecommunications, a switch is a network device that
selects a path or circuit for sending a unit of data to its
next destination) of some kind. The distinction seems to be
that the hub is the point where data comes together and the
switch is what determines how and where data is forwarded
from the place where data comes together. A hub is a hardware
device that acts as a central connecting point and joins lines
in a star network configuration.
Who Needs Hubs?
There is a simple way to determine whether you need a hub
on your LAN. If you are building a network with a star topology
and have two or more machines, you need a hub. There is, however,
an exception to this rule. If you are building a 10base-T
network and you have only two machines, you can connect them
to each other without using a hub.
Classification of Hubs
As you may have already guessed, hubs perform a crucial function
for star topology networks. There are many different types
of hubs, each offering specific features that allow you to
provide varying levels of service.
Passive Hubs: Passive hubs, as the name suggests, are rather
quiescent creatures. Hubs dont enhance the performance
of your LAN. They simply take all of the packets they receive
on a single port and rebroadcast them across all ports. Passive
hubs commonly have one 10base-2 port in addition to the RJ-45
connectors that connect each LAN device.
Active Hubs: Active hubs actually do something other than
simply rebroadcast data. Generally, they have all of the features
of passive hubs, with the added bonus of actually watching
the data being sent out. Active hubs use a technology called
store and forward where the hubs actually look at the data
they are transmitting before sending it. Active hubs are more
expensive than simple, passive hubs and can be purchased in
many configurations with various numbers and port types.
Managed Hubs: Managed hubs allow a network administrator to
monitor and configure them from a remote location. These smart
hubs can be used to fine tune a network's efficiency, allow
only certain kinds of traffic on the network, and much more.
Using the Simple Network Management Protocol, or SNMP, they
give administrators the power and flexibility to fix network
problems quickly as they arise. Because of their advanced
management features, they're usually a lot more expensive
than other hubs.
Features to look for
Here is the list of key features to look for when buying
Auto-sensing or dual-speed 10/100: Hubs with these
features can run at both 10 Mbps and 100 Mbps speeds simultaneously
on each port, making them extremely flexible. Recommended
for all types of networks, large and small, old and new, and
especially networks that have both 10 Mbps and 100 Mbps hardware.
Stackable: Hubs with this option are the most expandable.
They can be stacked together, and when stacked, they operate
as a single hub, providing more tightly integrated performance
over standard hubs when networks are in need of expansion.
SNMP: A hub that supports the Simple Network Management
Protocol allows a network manager to configure the hub from
anywhere on the network. SNMP can provide managers with network
traffic levels, error summaries, and much more. A good number
of the hubs above can be equipped to support SNMP. SNMP is
best used on networks in buildings with lots of floors, or
for LANs with fifty or more users. These hubs are recommended
for large networks requiring traffic monitoring.
Standard 10BaseT or 100BaseT: A 10BaseT hub supports
10 Mbps speeds were as a 100BaseT supports 100 Mbps speeds.
A standard 10 Mbps hub cannot be connected to a standard 100
Mbps hub unless a special device called a switch or an auto-sensing
hub is used in between. Recommend standard 100 Mbps or 10
Mbps hubs for brand new networks that don't need immediate
expansion. Remember that hubs run at half duplex. When you
need full duplex communication, choose a switch.
Combined features: Some hubs combine two or more of
the features above. A 10/100 auto-sensing hub might also be
stackable, and it may even come with SNMP management. Some
hubs may also come with the option of adding additional features
later on; many hubs, for instance, have plug-in modules that
can add SNMP or fiber features as the network becomes more
complex. Combined-feature hubs like 10/100 auto-sensing stackable
models offer the maximum in flexibility and expansion for
both small and large networks. They're good for new networks
just starting out, or existing networks that plan on expanding
in the future.
Mahesh Rathod can be reached at firstname.lastname@example.org
to remember when buying a hub
Hubs connect nodes of all kinds together: A standard hub,
for example, might have workstations, file servers, print
servers, hubs, and other nodes plugged into it with networking
All hubs can be uplinked together: A hub that has an uplink
port can be connected directly to a second hub with a regular
straight-through network cable. If neither hub has an uplink
port, a crossover cable can be used for uplinking.
Hubs decrease in performance as more users are added: If a
hub supports a speed of 100 Mbps, and 5 users are connected
to it, each users will receive only 20 Mpbs of available bandwidth.
This is fine for hubs that only service a small number of
users, but as more users or hubs are added to the network,
a switch should be installed to improve performance.
To make things easy, try to use hubs that have enough ports
to service all of the nodes of the network. If there are 5
users, the hub should have at least 8 ports to accommodate
expansion needs. Like most things, though, hubs are expandable,
so a customer can always add more hubs in the future.
8 port 10/100Mbps - Rs 5200
Intel 8 port 10/100Mbps - Rs 6250
Edimax 8 port 10/100Mbps - Rs 2600
Ace 8 port 10Mbps - Rs 1700
Dlink 8 port 10Mbps - Rs 2100