Pathology

Organic chemistry

Service (business)

Computer network

Service layer

Operating system

Software deployment

The Internet

Fuzz testing

World Wide Web

Software engineering

Transport Layer Security

Economy

Encryption

Economics

Chemistry

Application layer

Alternative medicine

Software

Layer (electronics)

Protocol (science)

Denial-of-service attack

Computer science

Quality of service

Computer security

Medicine

ACM Computing Surveys

Application layer Denial-of-Service (DoS) attacks are generated by exploiting vulnerabilities of the protocol implementation or its design. Unlike volumetric DoS attacks, these are stealthy in nature and target a specific application running on the victim. There are several attacks discovered against popular application layer protocols in recent years. In this article, we provide a structured and comprehensive survey of the existing application layer DoS attacks and defense mechanisms. We classify existing attacks and defense mechanisms into different categories, describe their working, and compare them based on relevant parameters. We conclude the article with directions for future research.

Application Layer Denial-of-Service Attacks and Defense Mechanisms