Nikolay Tcholtchev

Addressing Stability of Control-Loops in the Context of the GANA Architecture: Synchronization of Actions and Policies

As research on self-managing networks is on the rise, a very important question requiring answers is: How to ensure that all autonomic entities/elements in a network or in a single node work together harmoniously with the aim of maintaining service availability and good levels of quality of service (QoS) provided to the end users? In this paper, we propose to enhance the Generic Autonomic Network Architecture (GANA) --- a recently emerged architectural Reference-Model for Autonomic Networking, such that actions, policy enforcements and/or (re-) configurations, issued by different autonomic (decision making) entities, are synchronized in such a way that they lead to the best possible (long-term) reaction of the system to the challenging conditions the network is exposed to.

Scalable Markov Chain Based Algorithm for Fault-Isolation in Autonomic Networks

Research in the area of Autonomic Networks is on the rise. Autonomicity-realized through control loops, is an enabler for advanced self-manageability of network nodes and devices. Therefore, the specification and design of autonomic behaviors is required for each of the management functions defined by the well established FCAPS network management framework (Fault-, Configuration-, Accounting-, Performance- and Security-Management). In the context of Autonomic Fault-Management, mechanisms and algorithms are required that enable efficient and scalable interactions among the Fault-Management processes defined by the TMN (Telecommunications Management Network) standard. TMN defines Fault-Detection, Fault-Isolation, and Fault-Removal as the processes involved in Fault-Management. Therefore, in Autonomic Networks, some capabilities of Fault-Isolation must be in-built into a node and into the whole fundamental network architecture (apart from those aspects handled in the management plane), and its results must be fed into the embedded automatic Fault-Removal mechanisms. This imposes some scalability requirements on the employed algorithms. In this paper, we propose a novel scalable Markov Chain based algorithm for on-line Fault-Isolation. Furthermore, we analyze its computational and space complexity and evaluate its fault identification capabilities, as well as scaling properties on potential issues within an IPv6 network.

Autonomic Fault-Management and resilience from the perspective of the network operation personnel

Autonomic networks are an emerging technology which is promising to reduce the complexity of human-driven network management processes and enable a variety of so-called self-∗ features such as self-configuration, self-optimization, etc, inside the network devices and the network as a whole. Autonomic behaviors are widely understood as a control loop implemented by an autonomic entity that automates management processes and controls diverse aspects of a set of resources. Though automation is necessary and achievable, autonomic decision-making-elements of the network can not fully perform decisions on every task of the network without requiring some degree of “a human-in-the-loop” in some of the decisions. From the operators perspective, controllability of the control loop and decision notification from the autonomic network is a vital issue that needs to be addressed. In this paper we present our considerations on how an Autonomic Fault-Management control loop (“detect an incident” — “find the root cause behind it” — “remove the root cause”) can be controlled by the network operation personnel.

On the interplay of open data, cloud services and network providers towards electric mobility in smart cities

Quality of life in an urban environment depends strongly on ecological, social and mobility aspects. A major innovation in that context is given by the emergence of electric vehicles. Additionally, the explosive growth of social networks has shown how the Internet can be used to maintain and create communities, thereby bringing mutual benefits to the involved participants. Combining both, there is an obvious potential for the realization of collaborative electric vehicle sharing within a city. In this paper, we investigate one of the key aspects required to realize the vision of electric vehicle sharing - a cloud infrastructure for handling the required data. We propose a distributed architecture for the realization of such data cloud. Further, we demonstrate how ISP networks and the electric mobility data cloud can collaborate in order to provide efficient streaming of continuous data.

The Concept of a Mobility Data Cloud: Design, Implementation and Trials

The mobility data cloud is an Internet based platform for the integration of mobility related data from different data providers. It offers a framework for the acquisition, aggregation, provisioning, and analysis of mobility relevant data originating from various sources, e.g. Charging stations, gas stations, position of vehicles, battery charge condition of electric vehicles, utilization of vehicles, and data regarding public transport. These various types of data should facilitate the collaborative shared utilization of mobility resources such as electric vehicles, charging stations, etc. This paper presents the design and implementation of such an Internet based mobility data cloud. In addition, the presented prototype is evaluated based on trials in a European city.

Design and Evaluation of Techniques for Resilience and Survivability of the Routing Node

This paper presents the final results achieved within the EFIPSANS project on the topic of resilience and survivability in autonomic networks. In particular, the outcome of the investigation of the following issues is presented: adaptive level of recovery, unified architecture for autonomic routing resilience, synergies between autonomic fault-management and resilience in self-managing networks, as well as network resilience through autonomic reroute mechanism enhanced with multi-path node-to-node cooperation. The described ideas are supported by exhaustive descriptions and analyses featuring extensive validation results aimed to prove the applicability of the proposed concepts.

Addressing security issues in the autonomic Future Internet

We witness an ongoing intensive research towards the specification and implementation of autonomic behaviors for the Future Internet. Important issues that need to be addressed in that context are related to diverse security aspects of the emerging autonomic network technologies. In this paper, we present our research on security in autonomic networks based on the GANA reference model. We present a number of concepts and show how security can be addressed on the architectural level in an autonomic network.

Enhancing Cloud based Data Platforms for Smart Cities with Authentication and Authorization Features

The protection and securing of data platforms and related services plays a major role in the development of safety critical infrastructure for Smart Cities. Therefore, this paper specifies and develops an Integerated Component for Cloud Services (ISCS) that enables secure and trusted access to data and related services in the cloud. That means that the ISCS controls and handles access-related aspects such as authentication, authorization and registration. Furthermore, it is deployed and used in a large scale research project, in which it secures cloud services relating to electric mobility. ISCS is realized using OAuth and OpenID, whereas both are implemented by existing open source libraries. OAuth is a standard allowing services and applications to access safety critical resources in the cloud using a trustworthy infrastructure. OpenID is a popular standard originating from the web community, facilitating cross-domain authentication for portal users. The combination of both standards provides rich functionality, covering substantial aspects related to cloud service protection and security.

From Metadata Catalogs to Distributed Data Processing for Smart City Platforms and Services: A Study on the Interplay of CKAN and Hadoop

Smart Cities are emerging based on the idea of provisioning and processing large amounts of urban data for various use cases. Thereby, Urban Data Platforms are usually employed to accumulate and expose the large amounts of governmental (i.e. public sector), sensor, static and real-time data in order to enable the community to create valuable applications and services for future Smart Cities. Hitherto, the Open Data initiative was seen as the key driver to providing large amounts of data within a city. Open Data platforms employ so-called data registries in order to keep track of the available datasets at various sources spread throughout the city, with CKAN currently being among the most popular data catalog software worldwide. With the emergence of frameworks for large scale distributed computing and storage, such as Hadoop and the belonging distributed file systems (HDFS), there is an inherent need for bridging the worlds of metadata catalogs and distributed data processing towards the goal of providing sophisticated urban ICT services. The current paper constitutes a first attempt on this new field, by prototyping and evaluating components that enable the collaboration and interplay between CKAN and Hadoop/HDFS. This interplay is realized through extensions to CKAN and its harvesting process and its benefits are demonstrated by belonging case studies.

Systematic Analysis of Practical Issues in Test Automation for Communication Based Systems

This paper is about issues experienced along testing large-scale industrial products, with safety and security critical relevance. The challenges in testing - several thousand requirements for several product variants and various configurations - were addressed by test execution automation. However, since principal testing concepts as well as architectural concepts were ignored or poorly implemented, the test automation activities faced various difficulties within the considered projects. The current paper presents these issues in an abstracted manner and discusses possible solutions.