Hub Technology

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					                      Hubs, Routers and Switches


Some technicians have a tendency to use the terms routers, hubs and switches
interchangeably. One moment they are talking about the switch. then they were discussing the
router settings. Meanwhile, they only look at a box. Have you ever wondered what the
difference between the Hub, Switch and Router? and functions of the three devices are all very
different from one another, even if at the time they are integrated into one device.



Understanding Hub and Router Switch



HUB



A common connection terminal devices in the network.

Hub is generally used to connect the LAN segments. hub contains multiple ports. When a
packet arrives at one port, the port is copied to the other ports so that all segments of the LAN
can see all packets.



Switch



In the network, devices such as filters and packets between LAN segments. Switches operate at
data link layer (layer 2) and sometimes the network layer (layer 3) of the OSI Reference Model
and therefore support the protocol packets. LANs that use switches to join segments of the LAN
is set to activate or, in the case of Ethernet networks, Ethernet LAN is enabled.
Router



A device used together with packet data network. Router to connect to at least two networks,
commonly two LANs or the

Routers use headers and forwarding tables to determine the best path to continue the packets,
and they use protocols such as ICMP to communicate with each other and configure the best
route between two hosts.



Difference



Now the router has become sort of a key tool in combining the features and functions of the
router and switch / hub into a single unit. So the meaning of these devices can be a bit
misleading - especially for those just learning the computer network.



Features routers, hubs and switches are very different from each other, even if all these tools
are integrated into one device. We start with the hub and the switch because both devices have
the same role in the network. Each serves as a central connection for all network equipment
and handle data type known as frames. Frames carry your data. When a frame is received, it is
amplified and then transmitted to the PC port of destination. The big difference between the
two devices are presented frame method.



In a hub, a frame work to deliver or "broadcast (publish)" to each terminal. No matter that the
frame is only used for one port. hub has no way to distinguish between the frame where the
port should be sent. Pass along to make sure that each port will reach the goal. In this
equipment a lot of traffic on the network and can cause poor response time or slow network.



In addition, the specifications 10/100Mbps hub must share with each port. So when only one
PC is used, will have access to the maximum bandwidth available. However, if some PC
operating or in use on the network, the bandwidth will be distributed to all PCs, which will
reduce performance.
A Switch, keep records of device MAC address to connect. With this information, a switch can
identify system mounted on a terminal. So, when a frame is received, the software knows the
exact port to send data, without significantly increasing network response time.



And, unlike a hub, with specifications 10/100Mbps switch will allocate the full amount for each
port 10/100Mbps her. So regardless of the number of PCs transmitting, users will always have
access to the maximum amount of bandwidth. This is for the reasons why the switch is
considered to be a much better choice of hub.



Router is a device that is completely different to the equipment that has been described above.
When a hub or switch associated with the transmission frame, the router function is to route
packets to other packet networks until it finally reached its goal. One of the main features of a
package is that not only contain data, but the destination address where it will go.



Routers usually connect to at least two networks, commonly two Local Area Network (LAN) or
Wide Area Network (WAN) or LAN and ISP networks. for example, a PC or workgroup and
EarthLink. Routers are located at gateways, where two or more networks connect. Using
headers and forwarding tables, routers determine the best path to forward packets. Routers
use protocols such as ICMP to communicate with each other and configure the best route
between two hosts.



Now, many services are integrated into some broadband router. A router typically has 4 to 8
port Ethernet switch (or hub) and Network Address Translator (NAT). In addition, it is usually
already include Dynamic Host Configuration Protocol (DHCP) server, Domain Name Service
(DNS) proxy server and firewall hardware to protect the LAN from malicious intrusions from the
Internet.



All routers have a WAN port to connect to a DSL or cable modem for broadband internet
connection and a switch that is integrated, allowing users to easily create a LAN system. This
allows all PCs on the LAN to have access to Internet and Windows file sharing and printer
services.
Some routers have a WAN port and a single LAN port and is designed to connect the existing
LAN hub or switch to a WAN. Ethernet switches and hubs can be connected to a PC router with
multiple ports to expand the LAN. Depending on the capabilities (kinds of available ports) of the
router and switch, or hub, a connection between the router and switches / hubs may require
straight-through or crossover (null-modem) cable. Some routers even have USB ports, and
more generally, a wireless access point is transmitted from them.



Some routers are higher or business class routers will also incorporate a serial port to connect
to an external dial-up modem, which is useful as a backup in case of primary broadband
connection go down, and built in LAN printer server and printer port.



Besides the inherent protection features provided by the NAT, the router also has a built-in
configuration, hardware based firewall. Firewall capabilities can range from very basic, and up
to the advanced. Among the capabilities found on the main router is the router allows
configuring TCP / UDP port for games, chat, and the like, on the LAN behind the firewall.



So, in short, a hub glues together an Ethernet network segment, the switch can connect
multiple Ethernet segments more efficiently and a router can perform the functions of routing
TCP / IP packets between multiple LAN and / or WAN, and many others of course.

				
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