Internet Architecture
Lecture 7:
Connecting to the Internet II
&
How Internet/Television Connections
Work
Assistant Teacher Samraa Adnan Al-Asadi
1
How a Modem Makes Its Connection
1* Modems are controlled by software on your PC
using a language called the Hayes command set or AT
command set. When a modem is to be dialed, the first
command given it is to tell it to go off hook in other
words, to open a connection with the phone line. After
that, a command tells the modem to dial a telephone
number to make a connection.
Assistant Teacher Samraa Adnan Al-Asadi
2
How a Modem Makes Its Connection
Assistant Teacher Samraa Adnan Al-Asadi
3
How a Modem Makes Its Connection
Assistant Teacher Samraa Adnan Al-Asadi
4
How a Modem Makes Its Connection
Assistant Teacher Samraa Adnan Al-Asadi
5
How a Modem Makes Its Connection
Assistant Teacher Samraa Adnan Al-Asadi
6
How a Modem Makes Its Connection
Assistant Teacher Samraa Adnan Al-Asadi
7
How Internet/Television Connections
Work
When people first began talking about the
"information superhighway" several years ago, it wasn't the
Internet they were talking about. Instead, it was television
and specifically cable television that they believed would
change the way we lived and worked. There were visions of
500 TV channels, "interactive television," shopping from
home, and customized news available whenever you wanted
it. This information superhighway was going to hook us all
together electronically so we could more easily
communicate and get information, services, goods, and
entertainment. It didn't pan out that way. Instead, the
Internet has become an information superhighway that can
do almost everything people imagined could be done by
using cable TV.
Assistant Teacher Samraa Adnan Al-Asadi
8
How Internet/Television Connections
Work
But the Internet is no longer the sole driving force behind
the information superhighway. Every day, TV and the Internet are
drawing closer to each other. The Internet is gaining more TVlike qualities, such as playing videos and music, to broadcasting
live video feeds. Television technology is starting to use the
Internet to add interactivity to the television experience.
In fact, television and the Internet are already merging.
Soon you'll be able to watch a sporting event and simultaneously
chat with others while you're watching all on the same screen.
Furthermore, when a batter comes up to bat during a baseball
game, you'll be able to use the Net to get detailed statistics about
the batter, and even past videos and highlights of his career.
Assistant Teacher Samraa Adnan Al-Asadi
9
How Internet/Television Connections
Work
A different technology enables you to browse the
Web using your television set. A set-top box connects your
TV to the Net via a modem, takes the signal from the
modem, and sends it to the TV. A remote control-like device
enables you to browse the Web while watching TV at the
same time. Interactive TV goes a step further and uses a settop box to enable interactivity with your PC, using Internet
technologies. At this point, no single standard exists for how
Internet-enhanced TV works, nor even an agreement on
which features such a service should have.
Finally, telephone companies are getting into the
business of delivering TV signals into people's homes over
fiber-optic lines. They do this using IPTV, which uses the
Internet's underlying protocols to deliver TV.
Assistant Teacher Samraa Adnan Al-Asadi
10
How Cable Modems Work
1*
The coaxial cable sometimes called a
broadband wire that comes into a home from a pole is
divided into two connections by a splitter inside the
home. One part of the wire goes to the normal set-top
box that provides cable TV access. The other part of the
wire goes to a cable modem, sometimes called a
broadband modem.
Assistant Teacher Samraa Adnan Al-Asadi
11
How Cable Modems Work
Assistant Teacher Samraa Adnan Al-Asadi
12
How Cable Modems Work
Assistant Teacher Samraa Adnan Al-Asadi
13
How Cable Modems Work
Assistant Teacher Samraa Adnan Al-Asadi
14
How Cable Modems Work
Assistant Teacher Samraa Adnan Al-Asadi
15
How Cable Modems Work
Assistant Teacher Samraa Adnan Al-Asadi
16
How Cable Modems Work
Assistant Teacher Samraa Adnan Al-Asadi
17
How Cable Modems Work
Assistant Teacher Samraa Adnan Al-Asadi
18
Thank you
Assistant Teacher Samraa Adnan Al-Asadi
19