Chapter 2 Technology Infrastructure

munchdrabNetworking and Communications

Oct 30, 2013 (3 years and 5 months ago)

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Chapter 2

Technology Infrastructure


The Internet and the World Wide Web

The Internet and the World Wide Web

E
-
MAIL

FTP

USENET


WWW

TELNET

THE INTERNET


HTTP Servers

(Hypertext Transfer Protocol)



Web Browsers

(Internet Explorer, Netscape Navigator,
Firefox))



Web Pages with

hyperlinks

Growth the World Wide Web

World Wide Web Components


Packet Switching/Routing


Networks (LANS & WANS)


TCP/IP Communications Protocol


Client/Server Computing


Web Pages


Internet Backbone


U.S.

Source:
http://www.accd.edu/sac/lrc/john/wwwtest2.htm


Internet Backbone
-

Global

Routing Demo

www.visualroute.com

http://pages.ebay.com.cn/welcome/index.html


Internet Connectivity

TCP/IP Protocol

IP

TCP

HTTP, FTP,
Telnet,
DNS,SMTP

Network Layer

Transport Layer

Application Layer

SSL
(Secure Sockets Layer)

Network Data Packets

101001

1101001

101101

The TCP/IP protocol controls assembly & disassembly
of a file into packets for transmission over the Internet

Packet
-
Switching Networks


Digital data are sliced into packets, and sent
over network on different paths then
reassembled at their destination.


Routers:

special purpose computers that
interconnect computer networks and route
packets to their ultimate destination


Routers use routing algorithms to ensure
packets take the best available path

IP Addressing

Internet Protocol Version 4 (IPv4)


A 32
-
bit number to identify computers connected
to the Internet


Sample IP Address: 168.212.226.204

TCP/IP Application Suite

HTTP

FTP

Web Pages

File Transfer

TCP/IP Application Suite

SMTP

TELENET

E
-
Mail

Terminal Emulation

ICANN


ICANN is responsible for the global coordination of
the Internet's system of unique identifiers such as
domain names and addresses


Domain Names


A Domain Name is a set of words assigned to
a specific IP address.


Protocol Name + Domain Name or IP
Address = Uniform Resource Locator (URL).


ftp://www.pcwebopedia.com/stuff.exe


http://www.pcwebopedia.com/index.html

http://143.166.83.38














http://
www
.
secondleveldomain
.topleveldomain


Unrestricted

(
e.g.,

.com. .net, .org)


Restricted

(.edu, .gov, .mil)


Country

(e.g., .us, .cc, .tv)


New Domain Names
(
e.g.,

.aero, .biz,
.coop, .info, .jobs, .mobi, .museum, .name,
.pro, .travel)


Vanity Domain names

(e.g., .tv)

Domain Names

Domain Names

http://www.iana.org/gtld/gtld.htm



County Code Domain Names

http://www.iana.org/root
-
whois/index.html


Accredited Registries

http://www.icann.org/registrars/accredited
-
list.html


Domain Naming Issues


2
-
63 Characters (A
-
Z, 0
-
9, “
-
”)


No “
-
” at Beginning or End


Brand Names & Cybersquatting


Dot
-
Com is Most Respected


Not Case Sensitive


Typically Represents a Business, or
Product or Service Name, + Other Uses


About Registration & Name Ownership

http://www.oreillynet.com/onlamp/blog/2005/06/the_worlds_longest_domain_name.html


Client
-
Server Computing


Web
Client
Computer


Runs software called Web client software or
Web Browser software




Web
Server

Computer


Runs software called Web server software

Domain Name System (DNS)

The Domain Name System (DNS) associates
Domain Names with IP Addresses. Functionally, it’s
a Web Page Phone Book.

168.212.226.204


DNS


www.abc.com


URL is Resolved
to IP Address

Hosting Server


IP Address

168.212.226.204

abc.com
Home Page

IP

Addresses

Web Pages

Whois Search


Whois is used to determine who the URL is registered to.

Electronic Mail Protocols



SMTP

(Simple Mail Transfer Protocol)
-

specifies
the format of a mail message



POP

(Post Office Protocol)


used to retrieve
e
-
mail from a server.



MIME

(Multipurpose Internet Mail Extensions)


provides Support for graphics, audio & video
content.


W3C

The
World Wide Web Consortium

(W3C) is an
international consortium that develops protocols
and guidelines for the Web.





Standard Generalized Markup
Language (SGML)


Offers a system of marking up documents
that is independent of any software
application.


Used to Create Other Markup Languages.



Hypertext Markup Language
(HTML)


Prevalent markup language used to create
Web pages


HTML tags are interpreted by a Web browser
and are used by it to format the display of the
text


HTML links can be structured as:


Linear hyperlink structures


Hierarchical hyperlink structures

Extensible Markup Language (XML)



It includes data management capabilities that HTML
cannot provide


XML, HTML & XHTML:


XML does not have pre
-
defined tags.


XML tags do not specify how text appears on a Web page.


XHTML is a markup language written in XML that has a
stricter syntax than HTML.

Other Web Page Functionality


Scripting Languages: JavaScript, JScript,
Perl, and VBScript.


Cascading Style Sheets (CSS): Provide
pre
-
defined Web page formatting.

Intranets and Extranets


Intranet


Interconnected network that does not extend
beyond the organization that created it


Extranet


Intranet extended to include entities outside the
boundaries of an organization


Connects companies with suppliers, business
partners, or other authorized users

Networks


Public network


A network available to the public.


Private network


A private, leased
-
line connection between two
companies that physically connects their intranets.

Virtual Private Network (VPN)


VPN


An extranet that uses public networks and their
protocols


VPN software must be installed on the
computers at both ends of the transmission

Internet Connection Options


Bandwidth


Amount of data that can travel through a
communication line per unit of time


Net bandwidth


Actual speed that information travels

Voice
-
Grade Telephone Connections


POTS, or plain old telephone service


Uses existing telephone lines and an analog
modem


Provides bandwidth between 28 and 56 Kbps


Digital Subscriber Line (DSL)


Connection methods that do not use a modem


Integrated Services Digital Network (ISDN)


Bandwidths between 128 Kbps and 256 Kbps

Broadband Deployment

Broadband defined as greater than 200 Kbps



Asymmetric digital subscriber line (ADSL)


Cable Modem


Fixed Point Wireless Broadband


DSL


Satellite

Leased
-
Line Connections


DS0 (digital signal zero)


Telephone line designed to carry one digital signal


T1 line (also called a DS1)


Carries 24 DS0 lines and operates at 1.544 Mbps


Fractional T1


Provides service speeds of 128 Kbps and upward in
128
-
Kbps increments


T3

service (also called DS3)


Offers 44.736 Mbps

Wireless Connections

Bluetooth



Designed for personal use (Personal Area
Networks) over short distances (Up to 100
meters)


Speeds of up to 722 Kbps


Devices can discover each other and
exchange information automatically

Wireless Ethernet

(Wi
-
Fi


Wireless LANs)

Protocols based on IEEE 802.11 Standard

Mobile Networks


Cellular
-

Third
-
generation (3G)
Technology Cell Phones


Mobile commerce (m
-
commerce)

Internet 2



Internet2 or UCAID

(University Corporation for
Advanced Internet Development)


A nonprofit
consortium of universities and corporations which is
developing an advanced, high
-
speed network for
education and research.


Not to be confused with Web 2.0

-

which is the
unofficial “social networking & collaborative” Web.

Social Networking (Web 2.0)


Wikipedia, Blogs, RSS Feeds,
Facebook, YouTube


Nearly 2 in 5 U.S. Internet
Users Watched a YouTube
Video in September 2007.


Nearly 70 million people
viewed more than 2.5 billion
videos on YouTube.com.


More than 38 million people
viewed approximately 360
million videos on
MySpace.com

Source: comScore Video Metrix

Wikipedia

http://www.wikipedia.org/

Blogs

RSS Feeds

RSS Feeds

Second Life


Web 2.0 in Action

http://secondlife.com/whatis/economy_stats.php

http://
www.youtube.com/watch?v=b72CvvMuD6Q

Second Life


Web 2.0 in Action