Richard Macfarlane

Letter to the Editor: Formal security policy implementations in network firewalls

Network security should be based around formal security policies. From high-level natural language, non-technical, policies created by management, down to device and vendor specific policies, or configurations, written by network system administrators. There exists a multitude of research into policy-based network systems which has been undertaken. This paper provides an overview of the different type of policies relating to security in networks, and a taxonomy of the research into systems which have been proposed to support the network administrators in difficult tasks of creating, managing and deploying these policies.

Evaluation of TFTP DDoS amplification attack

Web threats are becoming a major issue for both governments and companies. Generally, web threats increased as much as 600% during last year (WebSense, 2013). This appears to be a significant issue, since many major businesses seem to provide these services. Denial of Service (DoS) attacks are one of the most significant web threats and generally their aim is to waste the resources of the target machine (Mirkovic & Reiher, 2004). Distributed Denial of Service (DDoS) attacks are typically executed from many sources and can result in large traffic flows. During last year 11% of DDoS attacks were over 60?Gbps (Prolexic, 2013a). The DDoS attacks are usually performed from the large botnets, which are networks of remotely controlled computers. There is an increasing effort by governments and companies to shut down the botnets (Dittrich, 2012), which has lead the attackers to look for alternative DDoS attack methods. One of the techniques to which attackers are returning to is DDoS amplification attacks.Amplification attacks use intermediate devices called amplifiers in order to amplify the attackers traffic. This work outlines an evaluation tool and evaluates an amplification attack based on the Trivial File Transfer Protocol (TFTP). This attack could have amplification factor of approximately 60, which rates highly alongside other researched amplification attacks. This could be a substantial issue globally, due to the fact this protocol is used in approximately 599,600 publicly open TFTP servers. Mitigation methods to this threat have also been considered and a variety of countermeasures are proposed. Effects of this attack on both amplifier and target were analysed based on the proposed metrics. While it has been reported that the breaching of TFTP would be possible (Schultz, 2013), this paper provides a complete methodology for the setup of the attack, and its verification.

Security Issues of a Publicly Accessible Cloud Computing Infrastructure

Edinburgh Napier University runs a custom cloud computing infrastructure for both student and public use. Such access carries dangers, both reputational and legal, as accidental or deliberate acts by users can be dangerous to other systems. This paper considers the experience gained in running this system, and offers techniques to help mitigate the dangers, and maintain high availability, while still providing a useful platform for educational purposes.

Distance Measurement Methods for Improved Insider Threat Detection

Insider threats are a considerable problem within cyber security and it is often difficult to detect these threats using signature detection. Increasing machine learning can provide a solution, but these methods often fail to take into account changes of behaviour of users. This work builds on a published method of detecting insider threats and applies Hidden Markov method on a CERT data set (CERT r4.2) and analyses a number of distance vector methods (Damerau–Levenshtein Distance, Cosine Distance, and Jaccard Distance) in order to detect changes of behaviour, which are shown to have success in determining different insider threats.