In a simple network, two computers (or other
networkable devices) make a direct connection with
each other and communicate over a wire or cable.
Local Area Network (LAN)
Local area networks often feature a group of computers
located in a home, school, or part of an ofﬁce building. Here the
switch controls trafﬁc to the local server and the ﬁrewall
protects the LAN from potential threats from the Internet.
Larger Wired Networks
Ethernet cables connect computers in a LAN, which then
connect out to the Internet Service Provider (ISP)
via phone or cable TV lines, which in turn connects to the
Internet Backbone made up of ﬁber optic cable.
Ethernet Cable Fiber Optic Cable
Core - Thin glass center of the ﬁber where the light travels
Cladding - Outer optical material surrounding the core that
reﬂects the light back into the core
Category 5 cable includes four twisted pairs Buffer coating - Plastic coating that protects the ﬁber
in a single cable jacket. from damage and moisture
This use of balanced lines helps preserve a
high signal-to-noise ratio.
Each line is drawn between two nodes, representing two IP addresses.
This is a small look at the backbone of the Internet.
How Does Information Travel in a Network?
All information is broken down into binary bytes which
travel along communication lines as packets.
Information is exchanged across networks through
protocols, which is a shared networking language that
determines connection and transfer of packets.
A wireless access point translates and
transmits information as radio waves.
Any device with a wireless receiver can
join the wireless network once it is given
an IP address.