In Christian theology the sybils was thought to have sharp knowledge, before the Christian theology, in Greek and Roman legend there was ten female prophets which are named as Sybyls. It is used to say that they participated in various places in the world. After the Greek and Roman legends this name was used in Christian theology. After the Christian theology this name was derived to England. In England, it was spelled Sybil instead sybyl. It became famous at a high scale in 19th century. Actually this name was used as Benjamin Disraeli’s novel “Sybil” in 1845.
This name was used in or before 2002 by Brian Zill at Microsoft research. It was used after the name of book Sybil which was the story of a woman with a dissociative …show more content…
R. Douceur. According to Douceur, the Sybil attack is an attack in which a single entity can control a substantial fraction of the system by presenting multiple identities Fig. 3.2 Honest and Sybil nodes
When an identity performs the function of multiple identities or we can say that a single node presents the behavior of multiple nodes then the particular single node is considered as a Sybil node. Actually in the network there is a condition imposed that a single node can function as single behavior. When a node presents the behaviour of multiple identities, this has to be considered as Sybil or malicious node. The Sybil attack can also occur in a system that is operating without a central authority. In mobile ad-hoc network, there is a technique for the detection of Sybil identities, in this technique the sending and receiving of manages are recorded over a shared broadcast communication channel. When a node sands massages to more than one node identities. The node spoofing the identities of the nodes is called malicious node. The nodes whose identities are spoofed are called Sybil …show more content…
Some variations are as follows
3.3.1 Route for Protocol
Routing may be sometimes very important, specially the multicast routing. Sybil attack disturbs the routing protocols in ad-hoc network. Disjoint paths may be the victim of Sybil attack. Another victim may be geographical routing in which the selfish nodes will appear at more than one place at the same time. This attack can be a huge type of attack if there are involved many fake identities in ad-hoc network. Examples include denial of service attack.
3.3.2 Voting along Reputation Scheme
This approach is based on voting system. Where there is a voting scheme is used instead of purpose. Purpose can be to produce report, to identify the behaviors of nodes. If the behaviors of all nodes or the behavior of a particular node is different from other's nodes, this is required to update the reputation system. The attacker’s trick for the attack will be same i.e. an attacker has to create many malicious nodes for overcoming on legitimate nodes. Also after making a removal of normal nodes, the illegal nodes design a defense system to keep themselves