TYPES OF ATTACK

Attackers
Any person or software that violates the security policy of the network system is called an attacker. Such a person or program intentionally attempts to gain an unauthorized access to information resources. Such an unauthorized activity uses specially moulded codes or techniques.Two types of attacks are:

Passive Attack

Active Attack

PASSIVE ATTACKS

Passive attack is one in which an attacker only monitors the transmission and accesses the data in an unauthorized manner. For example, user A sends a confidential message to user B and user C captures it or accesses it without the knowledge of A and B.

In passive attacks, the attacker only watches the transmission and does not try to modify data packets or don’t do any thing that user may realize that someone's watching him. But in case of an Active attack, the scenario is totally different. In this method, an attacker modifies the data stream or creates his own flash message along with watching of transmission.

Further it is divided into two types.

Release of Message Contents

Traffic Analysis

In release of message contents, the attacker only looks the messages and reads them in an unauthorized way. In traffic analysis, the attacker mask (does not change) the message in such a way that the authorized user either can not access it or can not understand the message properly.