Threats facing modern network infrastructures
Questions derived from the 642-552 – Securing Cisco Network Devices Exam Cisco Self-Test Software Practice Test.
Objective: Describe the security threats facing modern network infrastructures
SubObjective: Describe and list mitigation methods for common network attacks
Item Number: 642-5220.127.116.11
Single Answer, Multiple Choice
What characteristic of a Distributed Denial of Service (DDoS) attack differentiates it from a DoS attack?
- Attack can be originated from many sources.
- Many services can be scanned at the same time.
- A range of ports can be scanned at the same time.
- Many destination devices can be attacked at the same time.
A. Attack can be originated from many sources.
The option stating that a DDoS attack can be originated from many sources is correct.
The goal of a DoS attack is to deny a user or organization access to network services and resources. If a Web site is compromised by a DoS attack, legitimate users will also be denied access to the site. DoS attacks do not typically result in intrusion or illegal theft of information. Instead of providing access to unauthorized users, DoS attacks can cause much aggravation and cost to the target customer by preventing authorized access. Distributed DoS (DDoS) attacks amplify DoS attacks, in that a large number of compromised systems also known as zombies coordinate to attack target with bogus packets.
In a DDoS attack, the destination device remains the same but instead of one source of attack, the attacker uses many zombie machines. Therefore, the option stating that a range of ports can be scanned at the same time is incorrect.
Services scanning and port scanning are examples of reconnaissance attacks. By scanning available services or open ports DDoS attack will not trigger. Therefore, the options stating that many services can be scanned at the same time and that many destination devices can be attacked at the same time are incorrect.