Communications%20Protocol

1
Communications Protocol

• All communications between devices require that
  the devices agree on the format of the data. The
  set of rules defining a format is called a
  protocol. At the very least, a communications
  protocol must define the following
• rate of transmission (in baud or bps)
• whether transmission is to be synchronous or
  asynchronous
• whether data is to be transmitted in half-duplex
  or full-duplex mode
• In addition, protocols can include sophisticated
  techniques for detecting and recovering from
  transmission errors and for encoding and decoding
  data.

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TCP/IP Model1-25-06
Layer Name Common Components OSI Reference
Application HTTP, SMTP, POP3 FTP, DNS Application Presentation Session
Transport TCP, UDP Transport
Network IP, ICMP Network
Physical Ethernet, FDDI Data Link Physical
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TCP/IP Protocols

• Hypertext Transfer Protocol (HTTP)
• Web servers implement this protocol. Short for
  HyperText Transfer Protocol, the underlying
  protocol used by the World Wide Web. HTTP defines
  how messages are formatted and transmitted, and
  what actions Web servers and browsers should take
  in response to various commands. For example,
  when you enter a URL in your browser, this
  actually sends an HTTP command to the Web server
  directing it to fetch and transmit the requested
  Web page.

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TCP/IP Protocols

• Simple Mail Transfer Protocol (SMTP)
• Used by e-mail servers (and sometimes Web
  servers) to send e-mail. Short for Simple Mail
  Transfer Protocol, a protocol for sending e-mail
  messages between servers. Most e-mail systems
  that send mail over the Internet use SMTP to send
  messages from one server to another the messages
  can then be retrieved with an e-mail client using
  either POP or IMAP. In addition, SMTP is
  generally used to send messages from a mail
  client to a mail server. This is why you need to
  specify both the POP or IMAP server and the SMTP
  server when you configure your e-mail
  application.

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TCP/IP Protocols

• Post Office Protocol Version 3 (POP3)
• A protocol used to retrieve e-mail from a mail
  server. Most e-mail applications (sometimes
  called an e-mail client) use the POP protocol,
  although some can use the newer IMAP (Internet
  Message Access Protocol).
• There are two versions of POP. The first, called
  POP2, became a standard in the mid-80's and
  requires SMTP to send messages. The newer
  version, POP3, can be used with or without SMTP.

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TCP/IP Protocols

• IMAP - Short for Internet Message Access
  Protocol, a protocol for retrieving e-mail
  messages. The latest version, IMAP4, is similar
  to POP3 but supports some additional features.
  For example, with IMAP4, you can search through
  your e-mail messages for keywords while the
  messages are still on mail server. You can then
  choose which messages to download to your
  machine.
• IMAP was developed at Stanford University in 1986.

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TCP/IP Protocols

• File Transfer Protocol (FTP)
• The protocol for exchanging files over the
  Internet. FTP works in the same way as HTTP for
  transferring Web pages from a server to a user's
  browser and SMTP for transferring electronic mail
  across the Internet in that, like these
  technologies, FTP uses the Internet's TCP/IP
  protocols to enable data transfer.
• FTP is most commonly used to download a file from
  a server using the Internet or to upload a file
  to a server (e.g., uploading a Web page file to a
  server).

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TCP/IP Protocols

• DNS
• Short for Domain Name System (or Service or
  Server), an Internet service that translates
  domain names into IP addresses. Because domain
  names are alphabetic, they're easier to remember.
  The Internet however, is really based on IP
  addresses. Every time you use a domain name,
  therefore, a DNS service must translate the name
  into the corresponding IP address. For example,
  the domain name www.example.com might translate
  to 198.105.232.4.
• The DNS system is, in fact, its own network. If
  one DNS server doesn't know how to translate a
  particular domain name, it asks another one, and
  so on, until the correct IP address is returned.

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TCP/IP Protocols

• Transmission Control Protocol (TCP)
• Creates a reliable connection between two
  computers. TCP is one of the main protocols in
  TCP/IP networks. Whereas the IP protocol deals
  only with packets, TCP enables two hosts to
  establish a connection and exchange streams of
  data. TCP guarantees delivery of data and also
  guarantees that packets will be delivered in the
  same order in which they were sent.

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TCP/IP Protocols

• Internet Protocol (IP)
• Provides addressing scheme.. IP specifies the
  format of packets, also called datagrams, and the
  addressing scheme. Most networks combine IP with
  a higher-level protocol called Transmission
  Control Protocol (TCP), which establishes a
  virtual connection between a destination and a
  source.
• IP by itself is something like the postal system.
  It allows you to address a package and drop it in
  the system, but there's no direct link between
  you and the recipient. TCP/IP, on the other hand,
  establishes a connection between two hosts so
  that they can send messages back and forth for a
  period of time.
• The current version of IP is IPv4. A new version,
  called IPv6 or IPng, is under development.

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TCP/IP Protocols

• Internet Control Message Protocol (ICMP)
• Provides error messages. an extension to the
  Internet Protocol (IP) defined by RFC 792. ICMP
  supports packets containing error, control, and
  informational messages. The PING command, for
  example, uses ICMP to test an Internet
  connection.
• RFC - Short for Request for Comments, a series of
  notes about the Internet, started in 1969.An
  Internet Document can be submitted to the IETF by
  anyone, but the IETF decides if the document
  becomes an RFC. Eventually, if it gains enough
  interest, it may evolve into an Internet
  standard.

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TCP/IP Protocols

• User Datagram Protocol (UDP)
• Does not establish a connection, just sends
  messages.
• a connectionless protocol that, like TCP, runs on
  top of IP networks. Unlike TCP/IP, UDP/IP
  provides very few error recovery services,
  offering instead a direct way to send and receive
  datagrams over an IP network. It's used primarily
  for broadcasting messages over a network.

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Connecting Your LAN to the Internet

• Your ISP connects to the Internet
• A WAN connection is used between your building
  and the ISP
• A T-Carrier connection is often used
• A digital connection for voice and data

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Common T-Carrier Connections
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Other ways to Connect to the Internet

• Integrated services digital network (ISDN)
• Dial-up access
• Basic Rate Interface (BRI) up to 128 Kbps
• Primary Rate Interface (PRI) up to 1.544 Mbps
• Digital Subscriber Line (DSL)
• Often differing speeds for uploads and downloads
• Depending on type, up to 6.1 Mbps for downloads
  and 1.544 Mbps for uploads
• Cable Modem
• Shared access cable provided by cable TV company
  With the addition of users in the area transfer
  speeds will be reduced.

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Web Hosting Solutions

• Standard hosting
• Your site resides on the same computer with many
  other sites
• Cheapest solution
• Dedicated server
• You have a server that only you use
• Co-location
• Your own server is physically located at the
  company that does your Web hosting

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Web BrowsersBrowser Wars

• A software application used to locate and
  display Web pages. The two most popular browsers
  are Netscape Navigator and Microsoft Internet
  Explorer. Both of these are graphical browsers,
  which means that they can display graphics as
  well as text. In addition, most modern browsers
  can present multimedia information, including
  sound and video, though they require plug-ins for
  some formats such as Acrobat Reader, Flash
  Player.

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Web BrowsersNetscape

• The creation
• Netscape Navigator was developed by the team who
  had created the Mosaic web browser at the
  National Center for Supercomputing Applications.
  The company they created was initially named
  "Mosaic Communications Corporation" and their web
  browser "Mosaic", but a legal challenge from NCSA
  over the rights to the name resulted in the
  company and the product being renamed. The name
  "Netscape" was invented by sales representative
  Greg Sands.

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Web BrowsersMosaic 0.9
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Web BrowsersNetscape

• Release history
• Mosaic Netscape 0.9 October 13, 1994
• Netscape Navigator 1.0 December 15, 1994
• Netscape Navigator 1.1
• Netscape Navigator 1.22
• Netscape Navigator 2.0 September 18, 1995
• Netscape Navigator 2.01
• Netscape Navigator 2.02
• Netscape Navigator 3.0 August 19, 1996
• Netscape Navigator 3.01
• Netscape Navigator 3.02
• Netscape Navigator 3.03
• Netscape Navigator 3.04 October 4, 1997
• Netscape Navigator 4.0 June 1997

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Web BrowsersNetscape

• The rise of Netscape
• When the consumer internet revolution arrived in
  the mid to late 1990s, Netscape was well
  positioned to take advantage of it. With a good
  mix of features and an attractive licensing
  scheme that allowed free use for non-commercial
  purposes, the Netscape browser soon became the de
  facto standard, particularly on the Windows
  platform.

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Web BrowsersNetscape

• The fall of Netscape
• Microsoft saw Netscape's success as a clear
  threat to the dominant status of the Microsoft
  Windows operating system. It began a
  wide-reaching campaign to establish control over
  the browser market. Browser market share, it was
  reasoned, leads to control over internet
  standards, and that in turn would provide the
  opportunity to sell software and services.
  Microsoft licensed the Mosaic source code from
  Spyglass, Inc., an offshoot of the University of
  Illinois, and turned it into Internet Explorer.

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Web BrowsersNetscape

• The resulting battle between the two companies
  became known as the browser wars. Versions of IE
  were markedly inferior to contemporary versions
  of Netscape Navigator IE 3.0 (1996) began to
  catch up to its competition IE 4.0 (1997) was
  the first version that looked to have Netscape
  beaten, and IE 5.0 (1998) with many bug fixes and
  stability improvements saw Navigator's
  marketshare plummet below IE for the first time.

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Web BrowsersNetscape

• In March 1998, Netscape released most of the code
  base for Communicator under an open source
  license. The product named Netscape 5, which was
  intended to be the result, was never released, as
  managers decided that the code needed a complete
  rewrite. This product, taking growing
  contributions from the open-source community, was
  dubbed Mozilla, once the codename of the original
  Netscape Navigator. Netscape programmers gave
  Mozilla a different GUI and released it as
  Netscape 6 and later Netscape 7. After a lengthy
  public beta, Mozilla 1.0 was released on June 5,
  2002. The same code base, most notably the Gecko
  layout engine, became the basis of several
  standalone applications, including Firefox and
  Thunderbird.
• These products, however, came too late for
  Netscape as a business. Eventually Microsoft
  emerged victorious in the browser wars, and
  Netscape was acquired in 1999 by AOL.

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Web BrowsersInternet Explorer

• Internet Explorer 3 was the first major browser
  with Cascading Style Sheets (CSS) support
  released in August, 1996 and it could handle the
  PICS System for content metadata. The
  improvements were significant, compared to its
  main competitor at the time, Netscape Navigator.

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Web BrowsersInternet Explorer

• The browser was not widely used until version 4,
  which was released in October 1997 and was
  integrated with the Windows 98 operating system.
  This integration, however, was subject to
  numerous criticisms (see United States v.
  Microsoft). Version 5, released in September
  1998, was another significant release that
  supported bi-directional text, ruby characters,
  XML and XSL.

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Web BrowsersInternet Explorer

• Version 6 was released on August 27, 2001, a few
  weeks before Windows XP. This version included
  DHTML enhancements, content restricted inline
  frames, and better support of CSS level 1, DOM
  level 1 and SMIL 2.0. The MSXML engine was also
  updated to version 3.0. Other new features
  included a new version of Media bar, Windows
  Messenger integration, fault collection,
  automatic image resizing, P3P, and a new
  look-and-feel that is in line with the style of
  Windows XP

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Web BrowsersInternet Explorer

• For version 7.0 of Internet Explorer, set to ship
  with Windows Vista and as a separate download for
  Windows XP with Service Pack 2, large amounts of
  the architecture, including the security
  framework, have been completely overhauled.
  Partly as a result of these security
  enhancements, the browser will be a stand-alone
  application, rather than integrated with the
  Windows shell, and it will no longer be capable
  of acting as a file browser. The "beta 1" (build
  5112) and "beta 2 preview" (build 5299)
  pre-releases both operate in this new stand-alone
  manner.

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Web BrowsersDeveloping Web sites For

• Browsers have been criticized for implementing
  non-standard HTML markup extensions such as the
  BLINK tag, which is sometimes referred to as a
  symbol for Netscape's urge to develop extensions
  not standardized by the W3C, and even mentioned
  in the fictional Book of Mozilla. Both IE and
  Netscape have also been criticized for following
  actual web standards poorly, often lagging behind
  or supporting them very poorly or even
  incorrectly. This criticism wasn't very loud
  during the days of its popularity as web masters
  then often simply developed for Netscape
  Navigator, but came to be an increasing annoyance
  to webmasters who wish to provide backward and
  cross-browser compatibility. Today, many web
  masters still struggle with cross-browser
  compatibility do not choose to support old
  versions, due to their poor and invalid web
  standard implementations.

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Jeopardy
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Browsers
Netscape
Internet Explorer
100
100
100
200
200
200
300
300
300
400
400
400
500
500
500
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What are Browser Plug-ins?
Flash, Acrobat Reader

• Row 1, Col 1

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Who came up with the Name Netscape?
Greg Sands

• 1,2

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What is Internet Explorer?
IE

• 1,3

35
What is a payment method available for purchases
up to 4999.99 for which a blanket contract does
not exist?
P-Card

• 1,4

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What is a Web browser?
A software application used to locate and
display Web pages

• 2,1

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What is False?
TRUE OR FALSE The Netscape Browser came after
Microsofts Internet Explorer

• 2,2

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What are Cascading Style Sheets ?
CSS

• 2,3

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Which payment method can be used for all
purchases?
Receipt and invoice

• 2,4

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What is the National Center for Supercomputing
Applications?
NCSA

• 3,1

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Who Acquired Netscape in 1999?
AOL

• 3,2

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Who did Microsoft License its IE Source Code
From?
Spyglass, Inc

• 3,3

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What is a payment method that can be used for
purchases up to 100?
Petty Cash

• 3,4

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What are the two most popular browsers ?
Netscape Navigator and Microsoft Internet
Explorer

• 4,1

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What was Netscape Initially Called?
Mosaic

• 4,2

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What is IEs Latest Version?
Version 7.0

• 4,3

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What is a payment method that can be used for
purchases up to 5,000.00?
Direct Demand

• 4,4

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Who is the Instructor?
Michael Krueger.

• 5,1

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Which Version of Netscape was Never Released?
Netscape Version 5

• 5,2

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What is 1998?
Navigator's marketshare plummets below IE for
the first time.

• 5,3

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Who is the Pcard Program Manager?
Sharon Brandstatt 740-8762

• 5,4

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• Remember the more we LEARN, the more we GROW!