Patent · US Expired

Method for preventing transmission control protocol synchronous package flood attack

US7363652B2 · kind B2 · utility

4Cited by
0References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 3, 2003
Grant dateApr 22, 2008
Priority date
Expiry dateJan 4, 2026

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L63/145
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

The invention relates to a method for preventing TCP SYN package flood attack, and belongs to the computer network security field. First, the firewall receives a client a TCP SYN connection request package, and responses, as an agent of the server, an acknowledgement of the TCP SYN connection request package with zero window size to the client. Then, the firewall records information about the TCP SYN connection request package and checks whether the connection request is legal. When the firewall has received a TCP SYN response package from the server, it returns an acknowledgement of said TCP SYN response package. At the same time, the firewall, as an agent of the server, sends an acknowledgement packet with nonzero window size to the client for initiating data transmission from the client. After that, data packets are transferred between the client and the server forwarded by the firewall as an agent. With the invention method, it can guarantee that protected servers in a computer network will not be destroyed by TCP SYN package flood attack.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.