Abstract

The research presented aims to investigate the relationship between privacy and anonymisation in blockchain technologies on different fields of application. The study is carried out through a systematic literature review in different databases, obtaining in a first phase of selection 199 publications, of which 28 were selected for data extraction. The results obtained provide a strong relationship between privacy and anonymisation in most of the fields of application of blockchain, as well as a description of the techniques used for this purpose, such as Ring Signature, homomorphic encryption, k-anonymity or data obfuscation. Among the literature researched, some limitations and future lines of research on issues close to blockchain technology in the different fields of application can be detected. As conclusion, we extract the different degrees of application of privacy according to the mechanisms used and different techniques for the implementation of anonymisation, being one of the risks for privacy the traceability of the operations.

No abstract

Filtering is a very important issue in next generation networks. These networks consist of a relatively high number of resource constrained devices with very special features, such as managing frequent topology changes. At each topology change, the access control policy of all nodes of the network must be automatically modified. In order to manage these access control requirements, Firewalls have been proposed by several researchers. However, many of the problems of traditional firewalls are aggravated due to these networks particularities.In this paper we deeply analyze the local consistency problem in firewall rule sets, with special focus on automatic frequent rule set updates, which is the case of the dynamic nature of next generation networks. We propose a rule order independent local inconsistency detection algorithm to prevent automatic rule updates that can cause inconsistencies. The proposed algorithms have very low computational complexity as experimental results will show, and can be used in real time environments.

The design and management of firewall ACLs is a very hard and error-prone task. Part of this complexity comes from the fact that each firewall platform has its own low-level language with a different functionality, syntax, and development environment. Although high-level languages have been proposed to model firewall ACLs, none of them has been widely adopted by the industry due to a combination of factors: high complexity, no support of important features of firewalls, etc. In this paper the most important access control policy languages are reviewed, with special focus on the development of firewall ACLs. Based on this analysis, a new domain specific language for firewall ACLs (AFPL2) is proposed, supporting more features that other languages do not cover (e.g. NAT). As the result of our design methodology, AFPL2 is very lightweight and easy to use. AFPL2 can be translated to existing low-level firewall languages, or be directly interpreted by firewall platforms, and is an extension to a previously developed language.