The document describes several business models in e-commerce including B2B, B2C, C2B, C2C and B2G. It provides details on the B2B business model where businesses purchase goods or services directly from other businesses. An example is given of Company X supplying tires to Company Y, a bike manufacturer, representing a B2B relationship. The document also defines public key cryptography as a cryptographic system using a public and private key, with the public key known to all and private key known only to the recipient. Search engines are described as programs that search documents for keywords and return results, working through crawlers that index websites or via human submissions. Data mining is outlined as exploring large

1. 2010 SECTION-B
1. DESCRIBE ONE BUSINESS MODEL, BASED ON METHOD OF REVENUE GENERATION, GIVING AN
EXAMPLE
BUSINESS MODELS IN E-COMMERCE
B TO B- BUSINESS TO BUSINESS
B TO C- BUSINESS TO CUSTOMER
C TO B- CUSTOMER TO BUSINESS
C TO C- CUSTOMER TO CUSTOMER
B TO G- BUSINESS TO CUSTOMER
BUSINESS TO BUSINESS MODEL:-
B2B direct supports commerce transactions involving products, services, or information
between two businesses or parties. Typical B2B direct transactions occur between buyers,
suppliers, manufacturers, resellers, distributors, and trading partners.
The following diagram demonstrates a typical B2B direct business.
In a typical B2B direct business, businesses purchase goods or services directly from another
business. The selling business can be a wholesaler, a distributor, a manufacturer, or a retailer
who sells to buyers from other businesses.
Organizations that are not traditionally considered businesses, such as governments, may
sometimes implement sites based on the B2B direct business model. This occurs in such cases
where governments provide goods and services directly to businesses.
EXAMPLE:-
A COMPANY “X” IS DEALING IN TYRES AND ANOTHER COMPANY “Y” IS A MANUFACTURER OF
BIKES FOR THE INDIAN MARKET. COMPANY “X” AND “Y” COMES IN AN AGREEMENT WHERE IN
COMPANY “X” SUPPLIES TYRES TO COMPANY “Y” AND COMPANY “Y” WILL USE “x” PRODUCT AND WILL
DELIVER THE PRODUCT TO THE CUSTOMER . SO THIS IS CALLED A B TO B MODEL.

2. 2. DESCRIBE THE VAN USED BY THE INDIAN CUSTOMS AND EXCISE EDI SYSTEM
3. WHAT IS PUBLIC KEY CRYPTOGRAPHY? EXPLAIN
A cryptographic system that uses two keys -- a public key known to everyone and
a private or secret key known only to the recipient of the message.
Public key cryptography is becoming popular for transmitting information via the Internet. They
are extremely secure and relatively simple to use. The only difficulty with public-key systems is
that you need to know the recipient's public key to encrypt a message for him or her.
Also known as asymmetric-key encryption, public-key encryption uses two different keys at
once -- a combination of a private key and a public key. The private key is known only to
your computer, while the public key is given by your computer to any computer that wants to
communicate securely with it. To decode an encrypted message, a computer must use the
public key, provided by the originating computer, and its own private key. Although a message
sent from one computer to another won't be secure since the public key used for encryption is
published and available to anyone, anyone who picks it up can't read it without the private key.
The key pair is based on prime numbers (numbers that only have divisors of itself and one, such
as 2, 3, 5, 7, 11 and so on) of long length. This makes the system extremely secure, because
there is essentially an infinite number of prime numbers available, meaning there are nearly
infinite possibilities for keys. One very popular public-key encryption program is Pretty Good
Privacy (PGP), which allows you to encrypt almost anything.
4. WHAT ARE SEARCH ENGINES? HOW DO THEY WORK? WRITE IN BRIEF?
Search engines are programs that search documents for specified keywordsand returns a list of
the documents where the keywords were found. A search engine is really a general class of
programs.
Search Engines are the key to finding specific information on the vast expanse of the World
Wide Web. Without sophisticated search engines, it would be virtually impossible to locate
anything on the Web without knowing a specific URL.
There are basically three types of search engines:
Those that are powered by robots (called crawlers; ants or spiders)
Those that are powered by human submissions; and
Those that are a hybrid of the two.

3. Crawler-based search engines are those that use automated software agents (called crawlers)
that visit a Web site, read the information on the actual site, read the site's meta tags and also
follow the links that the site connects to performing indexing on all linked Web sites as well. The
crawler returns all that information back to a central depository, where the data is indexed. The
crawler will periodically return to the sites to check for any information that has changed. The
frequency with which this happens is determined by the administrators of the search engine.
Human-powered search engines rely on humans to submit information that is subsequently
indexed and catalogued. Only information that is submitted is put into the index
5. WHAT IS DATAMINING? WHAT ARE ITS TASKS?
Data mining is the exploration and analysis of large quantities of data in order to discover valid,
novel, potentially useful, and ultimately understandable patterns in data.
Task of data mining:-
Prediction Methods
Predict the value of a specific attribute (target/dependent variable)based on the value of other
attributes
o Classification
o Regression
Classification :-Typically used for predicting discrete target attributes (e.g.: Will this
online gamer purchase a virtual good?)
Regression :-Primarily used for predicting continuous target attributes (e.g.: What will
be the price of Facebook stock in 12 months from now?). The goal of these two
modeling tasks (enabled by machine learning algorithms) is to minimize the error
between the predicted value and the true value of the target attribute.
Description Methods
– Find human-interpretable patterns that describe the data
o Clustering
o Association Rule Discovery
Clustering :- Given a set of data points, each having a set of attributes, and a similarity
measure among them, find clusters such that
o Data points in one cluster are more similar to one another.
o Data points in separate clusters are less similar to one another.

4. Association rule discovery:-In data mining, association rule learning is a popular and
well researched method for discovering interesting relations between variables in large
databases. It is intended to identify strong rules discovered in databases using different
measures of interestingness.
For example, the rule found in the sales
data of a supermarket would indicate that if a customer buys onions and potatoes
together, he or she is likely to also buy hamburger meat