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Domain Generation Algorithms (DGA’s) have been employed by botnet orchestrators for controlling infected hosts (bots), while evading detection by performing multiple DNS requests, mostly for non-existing domain names. With blacklists ineffective, modern DGA filtering methods rely on Machine Learning (ML). Emerging needs for higher intrusion detection accuracy lead to complex, non-interpretable black-box classifiers, thus requiring eXplainable Artificial Intelligence (XAI) techniques. In this paper, we utilize SHapley Additive exPlanation (SHAP) to derive model-agnostic, post-hoc interpretations on DGA name classifiers. This method is applied to binary supervised tree-based classifiers (e.g. eXtreme Gradient Boosting - XGBoost) and deep neural networks (Multi-Layer Perceptron - MLP) to assess domain name feature importance. SHAP visualization tools (summary, dependence, force plots) are used to rank features, investigate their effect on model decisions and determine their interactions. Specific interpretations are detailed for identifying names belonging to common DGA families pertaining to arithmetic, wordlist, hash and permutation based schemes. Learning and interpretations are based on up-to-date datasets, such as Tranco for benign and DGArchive for malicious names. Domain name features are extracted from dataset instances, thus limiting time-consuming and privacy-invasive database operations on historical data. Our experimental results demonstrate that SHAP enables explanations of XGBoost (the most accurate tree-based model) and MLP classifiers and indicates the characteristics of specific DGA schemes, commonly employed in attacks. In conclusion, we envision that XAI methods will expedite ML deployment in networking environments where justifications for black-box models are required.

This paper presents Policy-based Federation (PBF) architecture for interworked Future Internet Virtualized Infrastructures (VIs). Each VI is an individually managed autonomous domain. Users may request slices of virtual resources across the federation, managed and controlled via inter-domain policies that abide by agreed upon federated SLAs. The key component of our PBF architecture is a Policy Service, which provides support for intra-domain policies (Obligation, Authorization, Role-Based Access Control) and for inter-domain Delegation policies. Delegation policies reserve resources in remote domains, update the number of resources exchanged, set alien domain obligations for cross-domain resource provisioning and define the exchange of internal domain information through the execution of remote semantic queries. Key to the architecture is the PBF Policy Ontology that specifies common federation concepts within the context of a user slice and the PBF services that trigger management actions. A prototype of the proposed architecture was developed and deployed in a European Future Internet federated testbed. [ABSTRACT FROM AUTHOR]

We study the virtual machine live migration (LM) and disaster recovery (DR) from a networking perspective, considering long-distance networks, for example, between data centers. These networks are usually constrained by limited available bandwidth, increased latency and congestion, or high cost of use when dedicated network resources are used, while their exact characteristics cannot be controlled. LM and DR present several challenges due to the large amounts of data that need to be transferred over long-distance networks, which increase with the number of migrated or protected resources. In this context, our work presents the way LM and DR are currently being performed and their operation in long-distance networking environments, discussing related issues and bottlenecks and surveying other works. We also present the way networks are evolving today and the new technologies and protocols (e.g., software-defined networking, or SDN, and flexible optical networks) that can be used to boost the efficiency of LM and DR over long distances. Traffic redirection in a long-distance environment is also an important part of the whole equation, since it directly affects the transparency of LM and DR. Related works and solutions both from academia and the industry are presented. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to explore and present a higher education initiative towards the training and development of Eastern European citizens, who migrate to Greece, in pursuit of bettering their economic conditions and, simultaneously, become evolving social entities, adaptable to heterogeneous environments. Design/methodology/approach – Motivated by the motto "education for all", the initiative is based on data drawn from local and public authorities and interviews that were carried out with immigrants, mainly from Albania and Ukraine. Findings – This paper proposes a learning policy and training mechanism for foreigners and the establishment of a Mediator Office providing educational services. Research limitations/implications – Further efforts are necessary to improve the teaching content in order to be in full conformity with the characteristics and requirements of non-native learners. Practical implications – Some of the constraints hampering the implementation of this initiative are the lack of the necessary financial resources, the absence of legal framework, as well as the shortage of bilingual adult training and education instructors. Originality/value – There have been limited autonomous educational programmes concerning immigrants' lifelong learning provided by the Greek Ministry of Education, focused mainly on the Greek language and history learning. This work introduces a novel educational structure, which may be established in any higher education institution and which will involve anyone in any kind of subject, anytime and anywhere. [ABSTRACT FROM AUTHOR]

Rigorous peer-reviews are the basis of high-quality academic publishing. Thanks to the contribution of our reviewers, in 2021, the median time to first decision was 16 days and the median time to publication was 40 days. Thanks to the great efforts of our reviewers, I Sensors i was able to maintain its standards for the high quality of its published papers. [Extracted from the article]