Writing 5
Networking
Hub – A hub is
basically a multiport repeater. A hub connects multiple wires coming
from different branches, for example, the connector in star topology
which connects different stations. Hubs cannot filter data, so data
packets are sent to all connected devices. In other words, collision domain
of all hosts connected through Hub remains one. Also, they do not have
intelligence to find out best path for data packets which leads to
inefficiencies and wastage.
Bridge – A bridge
operates at data link layer. A bridge is a repeater, with add on
functionality of filtering content by reading the MAC addresses of
source and destination. It is also used for interconnecting two LANs
working on the same protocol. It has a single input and single output
port, thus making it a 2 port device.
Switch – A switch is a multi port bridge with a
buffer and a design that can boost its efficiency(large number of ports
imply less traffic) and performance. Switch is data link layer
device. Switch can perform error checking before forwarding data, that
makes it very efficient as it does not forward packets that have errors
and forward good packets selectively to correct port only. In other
words, switch divides collision domain of hosts, but broadcast domain remains same.
Routers – A router
is a device like a switch that routes data packets based on their IP
addresses. Router is mainly a Network Layer device. Routers normally
connect LANs and WANs together and have a dynamically updating routing
table based on which they make decisions on routing the data packets.
Router divide broadcast domains of hosts connected through it.
