What is Denial-of-Service Attacks?

Denial of service attack is a cyber attack in which hackers attack the server/website/computer system/network which prevents the users from accessing the data available

Denial-of-service-attacks usually flood servers/networks with lots of traffic in order to affect user and makes it difficult for them to access. Moreover, an attack that crashes the server/network can be dealt with rebooting the system/network. But Flooding attacks are difficult to recover

The following can be indicated as DOS attacks as well :

• Degradation in the performance of networks, especially when you try to open some files on website/network
• Unable to reach a particular website/network
• Spam emails increase unexpectedly

Experts from cybersecurity world recommend no. of strategies for companies to defend the Denial-of-service Attack. One should always take measures to protect the system/network well in advance, to avoid any loss of data or leakage of information

How do a DOS Attacks work?

The main focus of DOS attacks is to overdose the capacity of targeted machine/server, resulting in Denial-of-service to an extent.

DOS Attacks typically falls into 2 Categories :

Butterfly overflow Attacks

In this type of attacks the memory buffer overflow an lead to machine consuming all the available hard disk space, memory or CPU Usage. This form of attacks usually results in a system crash, unusual server behaviors or slow-moving server which results in denial-of-service.

Flood Attacks

Attackers can over saturate the servers, by passing a large number of packets which results in oversaturation of the server capacity. In order to flood the server, the attackers should have more available bandwidth than their target bandwidth

TYPES OF DOS ATTACKS

DISTRIBUTED DOS

A Distributed DOS attack is a huge attack where the attacker uses more than one IP address, This leads to flooding of incoming traffic into servers and it becomes impossible to stop the attack. It also makes it very difficult to judge the authorized user traffic from the attack traffic

APPLICATION LAYER ATTACK

An application layer Distributed Denial-of-service attack also known as Layer 7 DDoS Attack. In this, the attackers attack the application layers of the processes. The attackers attack the specific function or feature of the system with an intention to disable the working of those features/functions.

ADVANCED PERSISTENT DOS

Advanced Persistent Denial-of-Services, is done by attackers who are well trained and well resourced and access to all computer guides and resources. This attack, attackers represents a threat that needs specialized monitoring and incident response services.

DENIAL-OF-SERVICE AS A SERVICE

Some of the service providers provide “booter” or “stresser” services, which are having web-based front-ends, and can accept payments online. Sold as stress-testing tools, they can be used as unauthorized denial-of-service attacks and allows hackers to access sensitive tools/information without the need for technical knowledge.