NETWORK BASICS

•NETWORK*** - A COMMUNICATIONS SYSTEM CREATED BY

LINKING TWO OR MORE DEVICES AND ESTABLISHING A

STANDARD METHODOLOGY IN WHICH THEY CAN

COMMUNICATE

HISTORY OF EXCHANGING DATA

•AT FIRST ‘MAINFRAME’ COMPUTERS

•EXCHANGED DATA VIA A ‘DUMB’ TERMINAL CONNECTED

DIRECTLY WITH THE MAINFRAME

•PERSONAL COMPUTERS / APPLES

•EXCHANGED DATA VIA FLOPPY DISKETTES

•PRIORITY NETWORKS ESTABLISHED (NOVELL)

UNIT OF MEASUREMENT FOR TELECOMMUNICATION DEVICES

•BANDWIDTH

•MEASURED IN BITS PER SECOND* (BPS)

•BROADBAND – (CABLE, DSL)

•NARROWBAND – (PHONE)

NETWORK BASICS

• TYPES OF NETWORKS INCLUDE:

• LOCAL AREA NETWORK* (LAN)

•WIDE AREA NETWORK (WAN)

CLIENT/SERVER NETWORKS

• CLIENT* - A COMPUTER THAT IS DESIGNED

TO REQUEST INFORMATION FROM A

SERVER (YOUR MACHINE)

• SERVER* - A COMPUTER THAT IS

DEDICATED TO PROVIDING

INFORMATION IN RESPONSE TO

EXTERNAL REQUESTS

MEDIA

• NETWORK TRANSMISSION MEDIA - REFERS TO THE VARIOUS TYPES

OF MEDIA USED TO CARRY THE SIGNAL BETWEEN COMPUTERS

•WIRE MEDIA (GUIDED - PHYSICAL)

•WIRELESS MEDIA

(UNGUIDED)

WIRE MEDIA – “GUIDED”

• WIRED MEDIA - TRANSMISSION MATERIAL

MANUFACTURED SO THAT SIGNALS WILL BE

TRANSFERRED OVER A PHYSICAL MEDIUM

TELEPHONE LINES

•ADVANTAGES-

• INEXPENSIVE

•WIDELY AVAILABLE

• EASY TO CONNECT

•DISADVANTAGES

• SLOWER SPEEDS (56 KBPS)

•DISTANCE LIMITATIONS

• SECURITY

•WEATHER

Called “Twisted Pair”

COAXIAL CABLE

•ADVANTAGES-

•WIDELY AVAILABLE

• EASY TO INSTALL

• FASTER THAN PHONE

•DISADVANTAGES

• SECURITY

• SHARED NETWORK –

MORE USERS SLOWER

SPEEDS

Cable into your house200 Mbps to 1 Gbps (download)Uploads are slower

FIBER OPTIC CABLE

•ADVANTAGES-

• SPEED (UP TO 10 GB)

• SECURITY

•MULTIPLE TRANSMISSIONS

•NOT EFFECTED BY WEATHER

•DISADVANTAGES

• EXPENSIVE

•DIFFICULT TO INSTALL

WIRELESS NETWORKS

7-12

Internet

RouterWireless Access Point

Smart Phone

Laptop

WIRELESS - UNGUIDED MEDIAMICROWAVE

•ADVANTAGES-

•DO NOT NEED

PHYSICAL WIRE

•UP TO 56 MBPS

•DISADVANTAGES

•SECURITY

•LINE OF SITE RESTRICTIONS

•WEATHER

SATELLITE - 22,000 MILES UP!

SATELLITES

• ADVANTAGES-

• TRANSMIT AROUND THE WORLD

• ONE UPLOAD OF DATA, MANY DOWNLOADS

• DISADVANTAGES

• EXPENSIVE

• TIME LAG (DISTANCE)

• SECURITY

BLUETOOTH• EMBEDS TINY RADIO TRANSMITTERS IN DEVICES

• USES UNLICENSED RADIO BANDWIDTH

• CHANGES FREQUENCY CONSTANTLY TO PREVENT INTERCEPTION

• DISADVANTAGES

• 5 TO 10 METER DISTANCE

• ADVANTAGES-

• WORLDWIDE USAGE DUE TO

UNLICENSED RADIO BANDWIDTH

• MANY DEVICES TO TALK TO EACH

OTHER

INFRARED• USES LIGHT WAVE TO TRANSMIT DATA

• DISADVANTAGES

• LINE OF SITE

• WALLS STOP IT

• ADVANTAGES-

• INSTALLATION IS EASY

• CUBICLES IN OFFICES CAN EASILY BE

RECONFIGURED

• WALLS STOP IT

CELLULAR

RADIO FREQUENCY IDENTIFICATION (RFID)

•RADIO FREQUENCY IDENTIFICATION (RFID) - USES ELECTRONIC

TAGS AND LABELS TO IDENTIFY OBJECTS WIRELESSLY OVER

SHORT DISTANCES

CHALLENGES OF BUSINESS MOBILITY

•PROTECTING AGAINST THEFT

•PROTECTING WIRELESS CONNECTIONS

•PREVENTING VIRUSES ON A MOBILE DEVICE

•ADDRESSING PRIVACY CONCERNS WITH RFID

INTERNET - HISTORY

• FORMED BY THE US GOVERNMENT AND UNIVERSITIES IN THE 1969 TO EXCHANGE

DATA

• WANTED TO AVOID THE “COLD WAR” SNOOPING.

EXPANSION OF THE INTERNET

•THE FEDERAL GOVERNMENT DECIDED TO NO LONGER PAY FOR

THE SWITCHING EQUIPMENT IN THE EARLY 1990’S.

•SPRINT, AT&T, MCI JUMPED IN AND FORMED THE BACKBONE OF

THE INTERNET TRAFFIC (FOR A FEE FROM YOUR INTERNET

PROVIDER)

HOW DOES IT WORK?

IP ADDRESSES

(INTERNET PROTOCOL)

TRANSLATES WWW.UNCW.EDU TO AN IP ADDRESS LIKE 152.20.201.15

IP (INTERNET PROTOCOL) ADDRESSES

• ALL ‘NODES’ ON THE INTERNET HAVE A UNIQUE IP ADDRESS (SIMILAR TO A PHONE NUMBER)

• AN IP ADDRESS IS UP TO 12 DIGITS IN 3 DIGIT PAIRS AS IN: XXX.XXX.XXX.XXX

• UNCW’S ‘AREA’ CODE: IS 152.20

• ENTROPY’S IP ADDRESS IS: 152.20.244.225

• THIS MACHINE IS: HTTP://WHATISMYIPADDRESS.COM/

INTERNET GROWTH

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