1. IT 2031 - ELECTRONIC COMMERCE THEORY NOTES

2. 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.

3. Packet switched networks
Packet Switched - network, files and messages are broken down into small pieces, called packets that are labeled electronically with their origins, sequences, and destination addresses.
Routing Packets – LAN, WAN

4. Routing Packets

5. 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 : = =3,631,433,189.

6. 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 for
privacy and security reasons

7. 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.

8. 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

9. Internet utility programmes

10. 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

11. 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.

12. Web Client/Server Communication

13. Two Tier Client / Server Architecture

14. Three Tier Client / Server Architecture

15. SGML, HTML XML