light introduction to DDoS

1. Milan Petrásek
1st June 2013
DDoS
Distributed Denial of
Service

2. • What is DDoS
• Types of DDoS attacks
• Example of attack
• How to protect
• Summary
Overview

3. What is a DDoS Attack?
During a Distributed Denial of Service (DDoS)
attack, compromised hosts (so called bots) coming
from distributed sources overwhelm the target with
illegitimate traffic so that the servers can not respond to
legitimate clients.
target
bots

4. DDoS types
Modern DDoS attacks are complex:
1. Volumetric and Flood DDoS Attacks
2. State-Exhausting DDoS Attacks
3. Application-Layer DDoS Attacks

5. DDoS example - SYN Flood

6. How to protect against DDoS
• It is not easy to try to do it yourself (DIY) –
this is very complex area.
• Better way is cooperate with internet service
provider (ISP) or specialized security
company.
• Firewall is not a solution.
• You need specialized solution for protection
against DDoS attack.

7. • Internet isn't safe.
• Creating attacks is a business.
• DDoS is big issue on present internet.
• Unfortunately Czech Republic isn't exception -
March (2013) - we were witnesses large DDoS
attack against banks, telcos, media houses etc.
• It is good to be prepared – will be worse
Summary

8. • Wikipedia
http://en.wikipedia.org/wiki/SYN_flood
http://en.wikipedia.org/wiki/Denial-of-
service_attack
• CSIRT– Recapitulation of march attacks
http://csirt.cz/files/csirt/Rekapitulace-utoky-
20120311.pdf
Sources

9. Thank you
Questions