Q and A: What are DOS and DDOS Attacks?Q1. What is a DOS attack?Ans: DOS attack is short for Denial of Service attack. An attacker sends a lot of garbage traffic to a server, such that it consumes all the resources on the server, rendering it unusable to the legitimate users. In the worst case, a DOS can cause the server to shut down temporarily. Q2. Whats the difference between DOS and DDOS attacks?Ans: When a DOS attack originates from hundreds of Botnets (aka compromised PCs), servers that are controlled by a BotMaster and are targeting another specific server or a group of servers is called a DDOS attack (Distributed Denial of Service). When a single server is used to flood the traffic, it's called a DOS attack. Q3. How can I identify such an attack?Ans: You may experience unavailability of a web service or a site. Your access may denied to some servers or sites for a long period and you may see an obvious, sudden decrease in network performance. Q4. How many types of DOS/DDOS attacks can be performed?Ans: Types of DOS/DDOS attacks are numerous. Some of them include:1. ICMP Flooding or Ping Flooding.2. TCP SYN Flooding or UDP Flooding.3. Permanent DOS attacks.4. Distributed attack or DDOS.5. Teardrop, Nuke etc. Use this information for good in your pentesting efforts.