Transcript The Internet - Irwan Sembiring

The Internet
Dr. Irwan Sembiring, ST.,M.KOm
The ARPAnet
The predecessor to the modern Internet.

ARPAnet is the predecessor to the modern Internet. Originally,
provided the exchange of electronic mail coded as standard ASCII
text messages. Each message was small (1-10K) - one page.
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1969 Experimental prototype developed by DOD.
The First Internet
backbone (1969)
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The Internet

26 computers hooked up to the ARPANET by 1971; around 1,000
computers by 1984.
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Now a large, growing, connection of over 10,000 networks and
30+ million users in over 60 countries.

NUA Survey: 544.2 million on-line as of February 2002.
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The Internet
Network connecting other networks
The Federal Networking
Council
On October 24, 1995, the FNC unanimously passed a resolution
defining the term Internet. This definition was developed in
consultation with the leadership of the Internet and
Intellectual Property Rights (IPR) Communities.
 RESOLUTION: "The Federal Networking Council (FNC) agrees
that the following language reflects our definition of the term
"Internet". "Internet" refers to the global information system
that –

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is logically linked together by a globally unique address space
based on the Internet Protocol (IP) or its subsequent
extensions/follow-ons;
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is able to support communications using the Transmission Control
Protocol/Internet Protocol (TCP/IP) suite or its subsequent
extensions/follow-ups and/or other IP-compatible protocols; and
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provides, uses or makes accessible, either publicly or privately,
high level services layered on the communications and related
infrastructure described herein."
A shared infrastructure, owned by no one: Much like the
railway network, no one company owns it.
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http://www.fnc.gov/Internet_res.html

“Internet” refers to the global information
system that –
is logically linked together by a globally unique
address space based on the Internet Protocol (IP)
or its subsequent extensions/follow-ups.
 is able to support communications using the
Transmission Control Protocol/Internet Protocol
(TCP/IP) suite or it subsequent
extensions/follow-ons, and/or other IPcompatible protocols, and
 Provides, uses or makes accessible, either
publicly or privately, high level services layered
on the communications and related infrastructure
described herein.

Haviland & Barnes, The Digital Lexicon, 2002
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Development of the Internet
1956
USSR launches Sputnik, 1st satellite; USA
Department of Defense (DOD) forms Advanced
Research Projects Agency (ARPA)
1962
Packet-switched network concept
1969
DOD starts ARPANET for networking research
1974
Protocol for packet internetworking
Transmission Control Program (TCP)
1981
BITNET (Because Its Time Network) provided
widespread email access.
Minitel is deployed across France by French
Telecom
1982
Internet Protocol (IP) established
1984
Domain Name Server (DNS) introduced and
number of host is 1,000
The Internet
TCP/IP
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1986
NSFNET created a high speed backbone
(56Kbps) to interconnect supercomputer
centers
1987
Number of hosts breaks 10,000
1989
Number of hosts breaks 100,000 and NSFNET is
upgraded to T1 line (1.544 Mbps)
Commercial email carrier (Compuserve)
connects to the Internet
1990
ARPANET ceases to exist;
MCI mail connects to the Internet
1991
WAIS released by Thinking Machines Corporation
to aid information search
Gopher released by U of Minnesota
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1992
WWW released by CERN (a physics research
institute in Switzerland)
Number of hosts breaks 1,000,000
NSFNET upgraded to T3 line (44.736 Mbps)
1993
WWW annual growth rate 341,634%
Whitehouse goes online
[email protected]
United Nations & World Bank go on-line.
US National Infrastructure Act championed by Al
Gore.
Mosaic developed by National Supercomputer
Center
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1994
1995
1996
1998
The Internet
Netscape
Communities become wired to the Internet For
example, Blacksburg, VA - bus & movie
schedules on-line, town meetings, etc.
US Senate and House go on-line
Mass marketing frenzy on the Internet
USA sales at cybermalls grows to $200 million
versus $50 billion in catalog sales & $1.5 trillion
in total USA retail sales.
*.com sites exceed *.edu sites
Electronic commerce gets going seriously
The government uses the Internet for public
dissemination of information (or political
assassination ) by publishing Starr’s report on
the Internet.
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How Many Online?
As of February 2002
World Total
544.2 million
Africa
4.15 million
Asia/Pacific
157.49 million
Europe
171.35 million
Middle East
4.65 million
Canada & USA 181.23 million
Latin America
25.33 million
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TCP/IP
TCP/IP ensures that messages are properly routed
from sender to receiver and that these messages
arrive intact.
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The Internet architecture is based on the
standard TCP/IP protocol, designed to
connect any two networks which may be
very different in internal hardware,
software, and technical design.
Once two networks are interconnected,
communication with TCP/IP is enabled endto-end, so that any node on the Internet
has the ability to communicate with any
other no matter where they are.
This openness of design has enabled the
Internet architecture to grow to a global
scale.
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Packet Switching
TCP = TRANSMISSION
CONTROL
PROTOCOL
(Breaks messages into packets
and reassembles them)
IP = INTERNET
PROTOCOL
(Moves packets around
the Internet)
SOURCE: J. DECEMBER
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
Packet switching is “first come-first served”

It allows efficient sharing of expensive lines as senders
take turns transmitting packets
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Since TCP/IP is “connectionless”, each packet is routed
independently
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Each packet can take a different route!
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When congested, routers drop packets
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
TCP/IP supports packet switching

This ensures reliable communication despite the chaotic
traffic flow on the net
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The data flow is broken up into ~200 byte packets which
share the pipe, even though they originate in different
sources
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Routers send them along the pipes that have the lowest
traffic flow at a given point in time

Routing algorithms are used to calculate traffic flow
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Internet Protocol
(IP) address
Each computer on the Internet has a unique
numerical address, called an Internet Protocol (IP)
address, used to route packets to it across the
Internet. (analogy: your postal address enables the
postal system to send mail to your house from
anywhere around the world)
 The IP address gives the Internet routing protocols
the unique information they need to route packets of
information to your desktop from anywhere across
the Internet.
 If a machine needs to contact another by a domain
name, it first looks up the corresponding IP address
with the domain name service. The IP address is the
geographical descriptor of the virtual world, and the
addresses of both source and destination systems are
stored in the header of every packet that flows
across the Internet.
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Domain Name
System (DNS)
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The Domain Name System (DNS) consists of
a network of servers that map Internet
domain names like www.livinginternet.com
to a local IP addresses.
The DNS enables domain names to stay
constant while the underlying network
topology and IP addresses change.
This provides stability at the application
level while enabling network applications to
find and communicate with each other
using the Internet protocol no matter how
the underlying physical network changes.
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Internet Network
Topology
How we connect
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We access the Internet from home through
an Internet service provider (ISP). An ISP
connects to a regional network that is
connected to a national network.
At the office, a desktop computer might be
connected to a local area network with a
company connection to a corporate Intranet
connected to several national Internet
service providers.
In general, small local Internet service
providers connect to medium-sized regional
networks which connect to large national
networks, which then connect to very large
bandwidth networks on the Internet
backbone.
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Backbones
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Backbones, owned by large ISPs and telecom companies,
are made up of:
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MCI, Sprint, Qwest, IBM, ATT, ANS, etc.
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High-speed TCP/IP routers in a number of cities connected
by...
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High-speed data lines leased from long-distance exchange
carriers...
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Forming national “backbones” connecting those cities
Source: Howard Rosenbaum [email protected]
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
Backbone providers sell access to
individuals and companies within each
backbone city
Traffic between cities moves over the leasedlines of the backbone
 Leased lines are purchased from different longdistance companies for each city
 Some providers lease several lines from
different carriers to connect two cities
 If one carrier has a problem and the link is
lost, a connection through the other carrier is
used to maintaining the backbone.

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
Currently, backbones are generally 45
Mbps DS-3 or faster leased lines
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A backbone operator may link a half dozen
or a dozen major metropolitan areas using
DS-3 lines
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They also extend dozens or even hundreds of
less expensive 1.544 Mbps T-1 or DS-1 lines
to surrounding communities from the major
backbone cities

They extend from those points with yet less
expensive 56 Kbps leased lines
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Internet Exchange Points

The communications traffic on the Internet backbone is
exchanged at large Internet Exchange Points (IXP),
sometimes called Network Access Points (NAP) or
Metropolitan Area Exchanges (MAE), constituting the top
level of the Internet network topology.

The first five large NAP's in North America were
established in the 1990's in Chicago, New Jersey, San
Francisco, San Jose, and Washington, D.C.
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