4. DEFENSE MECHANISMS
This section highlights the preventive measures of all the attacks
mentioned through 3.1 to 3.9.It is to be noted that the list would
be very vast if we try to exhaustively list all the preventive
measures. So the list is restricted to only a handful of the
solutions.
4.1 DOS prevention
The mechanisms to prevent DoS attacks include payment for
network resources, pushback, strong authentication and
identification of traffic [1] [2]. One security technique uses
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authentication streams to secure the reprogramming process.
This divides a program binary into a series of messages, each of
which contains a hash of the next message. This mechanism
ensures that an intruder can‟t hijack an ongoing program
transmission, even if he or she knows the hashing mechanism.
This is because it would be almost impossible to construct a
message that matches the hash contained in the previous
message. A digitally signed advertisement, which contains the
program name, version number, and hash of the first message,
ensures that the process is securely initiated [2].
We can defeat many threats using existing encryption and
authentication mechanisms, and other techniques (such as
identifying jamming attacks) can alert network administrator s of
ongoing attacks or trigger techniques to conserve energy on
affected devices [14].Summary of DoS attack is given in table 1