Tomasz Bilski

Disaster’s Impact on Internet Performance – Case Study

The paper presents how disasters change Internet performance. In the first section, transmission performance measures are defined with description of expected values for such applications as VoIP and Video. Next section deals with performance monitoring tools and services. The main part of the paper is dedicated to analysis of exemplary damage and its impact on Internet performance. Meditteranean accident (in January 2008) with submarine cables breakage is described. The accident had serious impact on Internet performance. In the last part of the paper we will suggest some recommendations for future networks.

Fluctuations and Lasting Trends of QoS on Intercontinental Links

The paper presents an analysis of short- and long-term changes in the QoS of intercontinental connections. First we will show that despite fast and numerous advances in physical layer, link layer, router capacity and new telecommunication cables deployment, QoS measures are hardly progressing in long-term (years) perspective. Transatlantic (North America – Europe) connections will be thoroughly analyzed. Next we will show that due to submarine cable breakages temporary network performance is unpredictable. It may be much poorer than average and sometimes drops below the acceptable level – case study is provided. Even if the links are fully operational, due to the rerouting the QoS may deteriorate in the case of cable fault in another part of the World. The research is based mainly on data taken from IEPM (Internet End-to-end Performance Measurement) database.

Digital and biological storage systems — a quantitative comparison

The paper presents a quantitative comparison of digital/electronic and biological storage systems. Two biological storage systems are included: DNA and brain memory. First we will show some examples of digital-biological systems integration. In the main part of the paper, we discuss different storage aspects, mostly quantitative, such as: organization, functionality, data density, capacity, power consumption, redundancy, integrity, access time and data transfer rate. Numerous analogies between biological and electronic storage systems are pointed out. Finally, we will try to answer the question: which digital storage systems and media are the best equivalents for brain and DNA storage? The analysis of the storage systems resemblances and differences may facilitate to carry bioinformatics research.

A Formal Model for Data Storage Security Evaluation

Backup systems use LAN or WAN. The networks and remote systems are not managed by data owner. It is necessary to integrate network storage systems with security mechanisms. There are many solutions to the backup confidentiality problem. In a given application one has to select the solution according to many factors such as: security level, performance, key management issues and overall cost. The optimization problem may be solved with a use of simulation tools. Diverse, general and specific models have been proposed. Most of them deal only with parts of the problem. The model presented in the paper is more general. It deals simultaneously with all 3 security attributes. It deals with data lifecycle and utilizes storage and transmission convergence.

Parameterized Hash Functions

In this paper we describe a family of highly parameterized hash functions. This parameterization results in great flexibility between performance and security of the algorithm. The three basic functions, HaF-256, HaF-512 and HaF-1024 constitute this hash function family. Lengths of message digests are 256, 512 and 1024 bits respectively. The paper discusses the details of functions structure. The method used to generate function S-box is also described in detail.

QoS Predictability of Internet Services

The paper presents problems of QoS (Quality of Service) predictability of network services (mainly in WAN environment). In the first part we present general remarks on QoS predictability problem, mentioning some research projects and available resources. The main part of the paper deals with QoS predictability in long-term as well as short-term viewpoints. We will try to answer a question: is it possible to predict network QoS/performance level with a use of statistical data from the past? The term quality of service has many meanings ranging from the user’s qualitative perception of the service to a set of quantitative connection parameters (RTT (Round Trip Time), throughput, loss packet rate) necessary to achieve particular service quality. In the paper we will mostly use the second meaning of the term based on RFC 2386 [1]. Analyzed, statistical data on Internet performance are taken from the IEPM (Internet End-to-end Performance Measurement) database.

A Model for Storage Processes in Network Environment and Its Implementation

Computer networks are frequently used as a communication channel between applications and storage resources. The diversity of the architectures, communication protocols and user objectives induces vast research agenda. Both networks and storage systems have their models, used to analyze and optimize separately the two different aspects (transmission and storage) of information systems. On the other hand the crucial features of the services are similar - throughput, security, reliability. There are instances of the convergence between the tools and methods used in storage and transmission to achieve the same purposes. For example hard disk sector structure is similar to Ethernet frame. So, it should be possible to provide a single, universal model for transmission and storage processes. Such model may be used to analyze both processes jointly. Furthermore the model may be used to provide formal definitions of some storage processes such as backup, replication, migration.

New Challenges in Network Security

The purpose of the paper is to point out different security issues of network evolution and to point out new threats related to the network evolution. We will discuss such issues as: complexity of security tools, IPv4/IPv6 transition, new modes of operation, IoT (Internet of Things), BYOD (Bring Your Own Device), cloud computing, SDN (Software Defined Network), wireless transmission. The paper should be of interest to different groups of people, among them are researchers and designers in the security area, policy makers and users of modern networks. Streszczenie. Celem jest wskazanie aspektów bezpieczeństwa związanych z ewolucją sieci komputerowych. Przedstawiono takie zagadnienia jak: złożoność narzędzi bezpieczeństwa, przejście z IPv4 na IPv6, nowe tryby działania, Internet Rzeczy, BYOD (Bring Your Own Device), przetwarzanie w chmurach, SDN (Software Defined Network), transmisja bezprzewodowa. Artykuł powinien zainteresować różne grupy, w tym: osoby badające i projektujące zabezpieczenia, twórców polityk bezpieczeństwa i użytkowników sieci. (Nowe wyzwania dla bezpieczeństwa sieci komputerowych).

Quantitative Risk Analysis for Data Storage Systems

In IT systems quantitative risk analysis is a method for security risk assessment used as a part of risk management process which in turn is a part of security policy. The main advantage of the method (in comparison to other techniques) is its accuracy – a better start point for security policy definition. Obviously the accuracy is directly related to input data dependability. The basic problem of the method is related to acquisition of input data necessary to perform the analysis. Data should be complete and reliable. The main purpose of the paper is to define comprehensive set of data necessary for the quantitative risk analysis for data storage systems (including magnetic disks and solid state disks) and to discuss trustworthiness of the data. Such comprehensive set of data should include data related to storage technology, features of storage processes (e.g. compression, deduplication), security events probabilities. Some of the parameters are dynamic, they change in time, they are related to environmental conditions. Different sources, different means of data acquisition are presented together with discussion on trustworthiness and dependability of the acquired data in the second part of the paper.

IP Storage Security Analysis

The paper presents analysis of different methods used to protect IP storage systems. The problem is, if the existing tools and methods for securing common Internet services like WWW, VoIP are suitable to IP storage system protection? The necessary security services such as: authentication, integrity and encryption may be provided in many different ways. It is necessary to select optimal method for a given application. The main part of the paper is related to evaluation of various IP storage systems that utilize iSCSI protocol for transfer and IPSec protocol for protection. Several methods and implementations of security systems with different crypto module locations (client, server, storage medium) and with different implementations (software or hardware) are examined. The following attributes of the systems are analyzed: security level, performance/throughput overhead, cost, flexibility.