1 / 13

Denial of Service Datakom Ht08 Jesper Christensen, Patrick Johansson, Robert Kajic

A short introduction to DoS. Denial of Service Datakom Ht08 Jesper Christensen, Patrick Johansson, Robert Kajic. Introduction Examples Some known incidents Types of attacks DoS – Denial of Service DDoS – Distributed Denial of Service Flavours PDoS - Permanent Denial of Service

april
Download Presentation

Denial of Service Datakom Ht08 Jesper Christensen, Patrick Johansson, Robert Kajic

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. A short introduction to DoS Denial of Service Datakom Ht08 Jesper Christensen, Patrick Johansson, Robert Kajic

  2. Introduction • Examples • Some known incidents • Types of attacks • DoS – Denial of Service • DDoS – Distributed Denial of Service • Flavours • PDoS - Permanent Denial of Service • DRDoS(?) - Distributed Reflected Denial of Service • Unintentional • Prevention • Being prepared • Network infrastructure

  3. Introduction • A ”denial-of-service” or DoS attack is a security threat in which an attacker attempts to deny users from using a service by rendering some network, host or another piece of infrastructure unusable • Typically target sites or services hosted on high-profile web servers such as banks, credit card payment gateways, and even DNS root server

  4. Examples • Some examples of DoS attacks are: • ”Flooding” of a network which prevents legitimate network traffic • Disruption of connections between two machines in order to prevent access to a service • Preventing some individual from accessing a service • Disruption of a service to a specific system or person

  5. ”Flooding” of a network which prevents legitimate network traffic

  6. Disruption of connections between two machines in order to prevent access to a service

  7. Preventing some individual from accessing a service

  8. Disruption of a service to a specific system or person

  9. Some known incidents • DDoS attacks against the DNS Root servers • DNS Root servers are responsible for redirecting requests for a particular top domain to that top domains authorative dns servers. I.e. break them and you break the internet. • There have been two major DoS attacks against the root servers • 2002, 9 of 13 servers • 2007, 3 of 13 servers • More recent attacks • Digg.com - social networking site • September 2008, 6 hours downtime • Polisen.se • 1-2 of June 2006 the Swedish police website was subject to an attack originating from multiple countries, probably as a response to the raid on The Pirate Bay. • Simple attack, started out by many people linking to / downloading a picture from the site.

  10. Types of attacks • DoS • Consumption of scarce, limited, or non-renewable resources • Destruction or alteration of configuration information • Ex. • Smurf attack – relies on misconfigured network devices that allow packets to be sent to all computer hosts on a particular network via the broadcast address of the network, rather than a specific machine. By spoofing the source adress the broadcast replies will flood the holder of the fake source address. • Ping flood - sends overwhelming number of ping packets. • SYN flood - sends a flood of TCP/SYN packets, often with a forged sender address.

  11. Types of attacks • DDoS - Distributed Denial of Service • Multiple systems participate in a DoS attack

  12. Types of attacks • Flavors • PDoS - Permanent Denial of Service • Permanently damaging hardware • Not many known examples • DRDoS – Distributed Reflected Denial of Service • Internet protocol spoofing • Unintentional ”attacks” • Slashdot effect • Utube.com sued Youtube.com

  13. Preventing DoS attacks • Being prepared • Secure individual hosts • Minimize number of running services • Setup disk quotas • Make backups • Etc. • Backup Systems • Backup Connections • Network infrastructure • Firewalls • Routers/Switches • IPS – Intrusion Prevention System

More Related