IT 2031 - ELECTRONIC COMMERCETHEORY NOTES

UNIT - II

UNIT II INFRASTRUCTURE FOR E COMMERCE

• Packet switched networks • TCP/IP protocol script • Internet utility programmes • SGML, HTML and XML • web client and servers • Web client/server architecture • intranet and extranets.

Packet switched networks

• Packet Switched - network, files and e-mail messages are broken down into small pieces, called packets that are labeled electronically with their origins, sequences, and destination addresses.

• Routing Packets – LAN, WAN

Routing Packets

TCP/IP• TCP controls the disassembly of a message or a file into

packets before it is transmitted over the Internet, and it controls the reassembly of those packets into their original formats when they reach their destinations.

• The IP specifies the addressing details for each packet, labeling each with the packet’s origination and destination addresses.

• IP addressing – IP v4 –used over 20 yrs.• Range : 23^2 = 4,294,967,296 • Example : 216.115.108.245

=11011000011100110110110011110101 =3,631,433,189.

Internet utility programmes

Finger and Ping Utilities :• Finger is a program that runs on UNIX operating

systems and allows a user to obtain• some information about other network users. A

Finger command yields a list of users who are logged on to a network, or reports the last time a user logged on to the network.

• Disabling the command on their systems forprivacy and security reasons

TCP/IP

• A program called Ping(Packet Internet Groper)- tests the connectivity between two computers connected to the Internet.

• Provides performance data about the connection between Internet computers, such as the number of computers(hops) between them.

Internet utility programmes

Tracert and Other Route-Tracing Programs :• Tracert (TRACE RouTe) sends data packets to

every computer on the path (Internet) between one computer and another computer and clocks the packets’ round-trip times

• Others - VisualRoute route-tracing program

Internet utility programmes

Internet utility programmes• Telnet and FTP Utilities - Telnet lets a client computer

give commands to programs running on a remote host.

• (FTP) is the part of the TCP/IP rules that defines the formats used to transfer files between TCP/IP-connected computers

• Indexing and Searching Utility Programs• Data Analysis Software - Analog, Keylime Software,

UrchinWeb Analytics,Web Side Story, and WebTrends• Link-Checking Utilities• Remote Server Administration

Web client and servers

• Major job : respond to requests from Web client computers.

• Main Elements : Hardware, operating system software, and Web server software.

• Types of sites : Development sites, Intranets, Extranets, Transaction-processing sites, Content-delivery sites.

• Web Client/Server Communication

Two Tier Client / Server Architecture

Three Tier Client / Server Architecture