Which of the following attacks come under the category of layer 2 Denial-of-Service attacks? Each correct answer represents a complete solution. Choose all that apply.

A.
SYN flood attack

B.
RF jamming attack

C.
Spoofing attack

D.
Password cracking

Explanation:
A SYN flood is a form of Denial-of-Service (DoS) attack in which an attacker sends a succession of SYN requests to a target’s system. When a client attempts to start a TCP connection to a server, the client and server exchange a series of messages, which normally runs as follows:
1.The client requests a connection by sending a SYN (synchronize) message to the server. 2.The server acknowledges this request by sending SYN-ACK back to the client. 3.The client responds with an ACK (acknowldgement), and the connection is established. The attack occurs when the attacker sends thousands and thousands of SYN packets to the victim, forcing the victim to wait for replies that never come. While the host is waiting for so many replies, it cannot accept any requests, so it becomes unavailable. Spoofing is a technique that makes a transmission appear to have come from an authentic source by forging the IP address, email address, caller ID, etc. In IP spoofing, a hacker modifies packet headers by using someone else’s IP address to hide his identity. However, spoofing cannot be used while surfing the Internet, chatting on-line, etc. because forging the source IP address causes the responses to be misdirected. Answer option B is incorrect. An RF jamming attack is a layer 1 Denial-of-Service (DoS) attack. Answer option D is incorrect. Password cracking comes under the category of hacker attacks.