Networking and Internet Basics - Computing Fundamentals - page 216

Network Hardware
A network adapter enables a computer to participate in the local area network. When a network
adapter is not built into the motherboard, but instead installed as an expansion board, it is called
a network interface card (NIC) . Each network adapter has a hardware address, called a media
access control (MAC) address , that is unique in all the world.

A switch is a box that provides a central gathering point for all the computers in an Ethernet
LAN. A wireless switch is called a wireless access point (WAP) . An earlier version of a switch,
called a hub , was not so intelligent. A router performs all the same functions as a switch, but it
also has an added bonus: It can direct traffic into and out of the LAN.

A repeater does just what the name implies—it repeats a network signal to strengthen it on its way
to its destination.

Most of the Ethernet cables in business and residential buildings are twisted-pair cable . Most
twisted-pair cable is unshielded twisted pair (UTP) . Shielded twisted pair (STP) contains this
extra lining. Coaxial cable is the type of cable used for cable TV connections. It is also used for
some networking, such as delivering cable Internet to a home. Fiber optic cable carries data in
pulses of light along a glass fiber.

Understanding and Connecting to.the Internet
The Internet began as a way of enabling research institutions and the military to share infor-
mation. Structurally, the Internet is a mesh of routers and servers connected to one another at
multiple points.

At the heart of the Internet are high-capacity, high-speed data pathways that are like superhigh-
ways for data. These pathways form the Internet's backbone .

Types of Internet connections include dial-up and broadband. A dial-up connection is established
using a dial-up modem . It is a very slow and inconvenient connection. Broadband connections
are usually always on. Types of broadband connections include cable modem , digital subscriber
line (DSL) , satellite Internet , and cell phone networks.

Key Terms
3G
4G
backbone
Bluetooth
broadband
cable modem
circuit-switched network
client
client/server network
coaxial cable
dial-up modem
digital subscriber line (DSL)
electromagnetic interference (EMI)
Ethernet
extranet
fiber optic cable
hub
infrared
Internet

Internet service provider (ISP)
intranet
latency
local area network (LAN)
media access control (MAC) address
metropolitan area network (MAN)
microwave communication system
network adapter
network interface card (NIC)
packet-switched network
pair
peer-to-peer network
personal area network (PAN)
protocol stack
protocol
repeater
router
satellite
satellite Internet