Networking Components
Mike Yardley
LTEC 4550
Assignment 3
We are going to cover a hub, switch, router, bridge, gateway, firewall
and wireless access point.
Hub

A hub is an inexpensive networking device
that connects multiple computers
together. A hub operates at layer 2 of the
OSI model. A hub makes communication
between computers possible by repeating
an incoming signal out each port except
the port from which the signal originated.
This technology handles collisions by using
a jamming signal on each port when a
collision is detected, forcing each device
to stop traffic and count down using a
timer before attempting to send another
signal. A hub used to be used for building
a network but now it is mainly used for
tapping into network communication. A
networking hub is a legacy technology
that has been replaced by Ethernet
switches in modern networks. A hub can
cost as little as a few dollars up to over
just one hundred dollars.
Switch

A network switch is a device that
operates at layer 2 of the OSI model
and was first produced in the 1990’s.
More modern switches operate at
multi levels of the OSI model and are
capable of routing which operate at
layer 3 of the OSI model. A network
switch at its basic level acts as a
bridge and uses learned MAC
addresses to determine where data
exits which port. A layer 3 switch is
capable routing traffic based on IP.
They can cost as little as 10s of
dollars or hundreds of thousands of
dollars for modern enterprise based
switches.
Router

A router is a device that operates
mainly within layer 3 of the OSI
model. This means that it deals
with the Internet Protocol (IP) and
forwards traffic based on
destination IP address. A router can
cost as little as thirty dollars as
part of a broadband modem to
upwards of several thousand
dollars.
Bridge

A bridge connects two separate
networks using layer 1 and 2 of the
OSI model. It is a function of
modern network switches and
routers. Bridges form a network
boundary by filtering traffic and
deciding whether to forward or
discard it by inspecting each
Ethernet frame.
Gateway

A gateway is device that can
interconnect separate networks
that use different protocols. They
tend to be placed at the edge of a
network and are usually in the
form of a firewall currently. They
also operate at any layer of the OSI
model. They can range in price
from your basic home router for
under one hundred dollars to tens
of thousands of dollars for an
enterprise class device.
Firewall

A firewall covers many different functions
these days and come in a wide variety of
features and functions. Current firewalls
operate at all levels of the OSI model.
They are usually implemented to cover
several different roles, such as a gateway,
intrusion prevention, VPN, site to site
VPN, virus/malware protection, data loss,
content filtering and they can be
configured in a high availability mode as
well. Firewalls can be used for different
bandwidth needs and currently go up to
and beyond 100GB connections. At my
work we use 2 NSA 4500 appliances in
failover mode. They can be very cheap
when it comes with your home router or
be very expensive depending on your
needs.
Wireless Access Point

Wireless access points are cable of
broadcasting a signal in a certain
frequency, usually 2.4GHZ or 5GHZ that a
configured device can attach to giving
them network access. They come from a
multitude of different vendors and prices.
Current APs are moving to a new standard
called 802.11AC, sporting data rates just
over 400mbp/s. They can be configured
per each access point or can be used with
a hardware based controller like come
cisco access points or be connected to a
cloud based controller. Access points are
very cheap on the consumer side costing
as little as twenty dollars to the
enterprise class costing over one thousand
dollars per access point.