Title: Improvement of Mitigation Techniques against SYN Flood Attack for Free and Open Source Firewalls

Issue Number: Vol. 9, No. 1
Year of Publication: March - 2019
Page Numbers: 8-21
Authors: Kosmas Kapis, Davis Nico Kyando
Journal Name: International Journal of Digital Information and Wireless Communications (IJDIWC)
- Hong Kong
DOI:  http://dx.doi.org/10.17781/P002549


Firewalls are very potential solutions to network security. Cyber-attacks have been seriously impacting technology operations and security applications which support many business processes and protect valuable information assets. Denial of service attacks specifically SYN flood attacks are highly rated to jeopardize network security by tampering with network applications like firewalls. Existing firewalls solutions are not secure enough to protect the network against SYN flood attacks. This paper reassesses Firewall’s SYN Flood mitigation techniques performance and presents an improvement model for minimizing the severity of the SYN flood attacks. The proposed model explores dynamic tweaking of TCP open timer, adjustment of firewall state table size and management of data size when the attack is detected. Experiment results of the model shows that CPU usage during SYN flood attacks hits 100% but when the improvement model is applied the CPU usage decreases by 24.6 % which is an improvement of CPU usage which is one of firewall's key resources.