Krzysztof Nowicki - Academia.edu (original) (raw)
Papers by Krzysztof Nowicki
Journal of Computer Science and Software Application, Dec 31, 2014
2011 3rd International Congress on Ultra Modern Telecommunications and Control Systems and Workshops, 2011
VoIP (Voice over IP) is a modern service with enormous potential for yet further growth. It uses ... more VoIP (Voice over IP) is a modern service with enormous potential for yet further growth. It uses the already available and universally implemented IP transport platform. One significant problem, however, is ensuring the Quality of Service, abbreviated QoS. This paper addresses exactly that issue. In an extensive investigation the influence of jitter buffers on QoS is being examined in depth. Two implementations, namely a passive FIFO buffer and an active PJSIP buffer are considered. The results obtained are presented in several diagrams and interpreted. They provide valuable insights and indications as to how procedures to ensure QoS in IP networks can be planned and implemented. The paper concludes with a summary and outlook on further work.
Lecture Notes in Computer Science, 2007
Despite the dynamic growth of wireless network systems, their presence in business-support infras... more Despite the dynamic growth of wireless network systems, their presence in business-support infrastructure has been limited. In the article we provide an overview of generic corporate network architecture and examine usefulness of available wireless network solutions in such systems. Following this overview we analyze new wireless network architecture which currently undergoes standardization process -wireless mesh. It can result in significant increase in both bandwidth and reliability of complex wireless systems, even to a level suitable for mission-critical business applications. In conclusion we point out research directions and topics which are critical for integration of wireless solutions into business-support network infrastructure as they differ from currently followed main line of standardization works on the subject.
New Technologies, 2011
In this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment ta... more In this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client architecture. Our research proved that such architecture, while well suited for didactic content distribution systems is ill-suited for knowledge assessment products. In our design we employed loosely-tied distributed system architecture, strict modularity, test and simulation-based knowledge and skill assessment and an our original communications package called Communication Abstraction Layer (ComAL), specifically designed to support communication functions of e-learning systems in diverse network conditions (including offline environment and content aware networks).The system was tested in production environment on Faculty of Electronics, Telecommunications and Informatics, Technical University of Gdansk with great success, reducing staff workload and increasing efficiency of didactic process. The tests also showed system's versatility in classroom, remote and blended learning environments.
Concepts, Methodologies, Tools and Applications, 2010
Abstract In this article we propose a novel e-learning system, dedicated strictly to knowledge as... more Abstract In this article we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client ...
CompEuro 1992 Proceedings Computer Systems and Software Engineering, 1992
[Conference Record] GLOBECOM '92 - Communications for Global Users: IEEE, 1992
An efficient and robust distributed protocol for packet radio LANs is presented. Called the coope... more An efficient and robust distributed protocol for packet radio LANs is presented. Called the cooperative random token (CRT) protocol, it is based on the concept of random reservation followed by explicit token passing. The protocol outperforms previous radio channel access protocols, while allowing for variable packet lengths and priorities and requiring no knowledge of the number, location, or identities of stations, no time slotting, and no network-wide feedback information about past transmissions. Station failures and/or transmission errors can be recovered from at the price of slight alterations to the original protocol. The results obtained via simulation suggest a high-speed radio LAN with Δ/T⩽0.1 and Δ/TR⩾5 as a preferred environment for the CRT protocol
Open Journal of Communications and Software, 2014
ABSTRACT The paper analyzes the problems of IPv4 to IPv6 migration processes and indicates the ar... more ABSTRACT The paper analyzes the problems of IPv4 to IPv6 migration processes and indicates the areas in which migration can be done without expensive replacement of hardware, software and organizational changes. This paper presents the migration tools developed for the SOHO network administrators. The tools provide theoretical knowledge and practical advices on migrating to IPv6 and enable automation of the migration process. The article presents basic problems encountered in migrating small networks environments to support IPv6. Problems were introduced along with proposals for migration methodologies and tools to assist in this process. The system supporting administrators with the IPv6 network migration was presented. The system consists of Migration Guide and Automated Migration Tool. They are interactive tools which allow the transmission of guidance on network migration.
2008 1st International Conference on Information Technology, 2008
Although Dynamic Host Configuration Protocol for IPv6 (DHCPv6) protocol was defined in 2003, it w... more Although Dynamic Host Configuration Protocol for IPv6 (DHCPv6) protocol was defined in 2003, it was designed as a framework rather than a complete solution to the automatic configuration in IPv6 networks. There are still some unsolved problems and new options yet to be defined. One example of such case is Fully Qualified Domain Name (FQDN) option, which final version has been published in late 2007. It describes DHCPv6 client and server behavior, but some important aspects remain unaddressed. Authors developed and released working open source implementation over a year before FQDN standard reached mature phase. This paper discuses those issues and recommends possible solutions. Another important development area in the DHCPv6 protocol is a lack of well defined authentication and authorization. Experimental AAA implementation has been developed and reached validation phase. Quick overview of the Dibbler project -a working, multi-platform, open-source DHCPv6 implementation -is also provided, its strengths, used solutions and validation methods used to prove its correctness are discussed. Conclusions and discussion regarding areas for further studies appears in the last section of this article.
Lecture Notes in Computer Science, 2010
IP networks are indispensable nowadays. They are among the most efficient platforms. The constant... more IP networks are indispensable nowadays. They are among the most efficient platforms. The constantly growing number of users and new services in these networks -the largest being the Internet -requires a good quality of any application used. Determining the QoS in real-time services is particularly important. This work is dedicated to exactly this aspect of the real-time service Video Telephony over IP (VToIP). First, the ITU-T standard H.323 for VToIP will be described and discussed briefly. Then, the performance of the H.263 codec in an ideal environment (without network impairments) will be analysed in detail. Following that, the performance of the codec H.263 with network impairments (packet loss being the main impairment factor) will be examined in detail. The paper finishes with a conclusion and an outlook.
2008 1st International Conference on Information Technology, 2008
Abstract This paper describes a system of geo-location of an IP user that would enable VoIP users... more Abstract This paper describes a system of geo-location of an IP user that would enable VoIP users to call 112. Basic requirement is fast (under 50 ms) determination of the commune of the subscriber. To obtain as accurate information as possible aggregation of several ...
Replacing the IPv4 protocol with IPv6 on the Internet is currently one of the aims of the Europea... more Replacing the IPv4 protocol with IPv6 on the Internet is currently one of the aims of the European Union policy. The main reason for this replacement is the effeteness of the addresses pool in the IPv4 protocol, which can cause serious complications in the evolution of the Internet and its adaptation in new areas, e.g., in next generation mobile telephony or the so called Internet of Things. Simultaneously, the addressing capabilities of the IPv6 protocol are practically unlimited and its new functionalities increase the attractiveness of its usage. The article discusses the problems connected with the IPv6 deployment on the Internet. Especially, the rules for realization of the IPv6 deployment and rules for cooperation of IPv4 with IPv6 (including cooperation tests) in network infrastructure and in applications are presented. Moreover, the European projects' results and the activity's directions of the national project Future Internet Engineering are discussed.
2011 IEEE/IPSJ International Symposium on Applications and the Internet, 2011
Abstract There are many reasons to deploy IPv6 protocol with IPv4 address space depletion being t... more Abstract There are many reasons to deploy IPv6 protocol with IPv4 address space depletion being the most indisputable. Unfortunately, migration to the IPv6 protocol seems slower than anticipated. To improve pace of the IPv6 deployment, authors of the article developed the ...
2010 Australasian Telecommunication Networks and Applications Conference, 2010
... Apr. 2010 [10] N. Moore, Optimistic Duplicate Address Detection (DAD) for IPv6, RFC 4429, I... more ... Apr. 2010 [10] N. Moore, Optimistic Duplicate Address Detection (DAD) for IPv6, RFC 4429, IETF, Apr. 2006. [11] S. Thomson, T. Narten, T.Jinmei IPv6 StatelessAddress Autoconfiguration, RFC 4862, IETF, Sep. 2007. [12 ...
Teletraffic Science and Engineering, 1994
Lecture Notes in Computer Science, 2004
Paper describes iSteering–a new method to control traffic in case of RPR network failure. There&a... more Paper describes iSteering–a new method to control traffic in case of RPR network failure. There's comparison of packet wrapping, steering and our proposed method iSteering, which can be used in case of transmitter/receiver or fiber failure. Numerical analysis for even and ...
Journal of Computer Science and Software Application, Dec 31, 2014
2011 3rd International Congress on Ultra Modern Telecommunications and Control Systems and Workshops, 2011
VoIP (Voice over IP) is a modern service with enormous potential for yet further growth. It uses ... more VoIP (Voice over IP) is a modern service with enormous potential for yet further growth. It uses the already available and universally implemented IP transport platform. One significant problem, however, is ensuring the Quality of Service, abbreviated QoS. This paper addresses exactly that issue. In an extensive investigation the influence of jitter buffers on QoS is being examined in depth. Two implementations, namely a passive FIFO buffer and an active PJSIP buffer are considered. The results obtained are presented in several diagrams and interpreted. They provide valuable insights and indications as to how procedures to ensure QoS in IP networks can be planned and implemented. The paper concludes with a summary and outlook on further work.
Lecture Notes in Computer Science, 2007
Despite the dynamic growth of wireless network systems, their presence in business-support infras... more Despite the dynamic growth of wireless network systems, their presence in business-support infrastructure has been limited. In the article we provide an overview of generic corporate network architecture and examine usefulness of available wireless network solutions in such systems. Following this overview we analyze new wireless network architecture which currently undergoes standardization process -wireless mesh. It can result in significant increase in both bandwidth and reliability of complex wireless systems, even to a level suitable for mission-critical business applications. In conclusion we point out research directions and topics which are critical for integration of wireless solutions into business-support network infrastructure as they differ from currently followed main line of standardization works on the subject.
New Technologies, 2011
In this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment ta... more In this paper we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client architecture. Our research proved that such architecture, while well suited for didactic content distribution systems is ill-suited for knowledge assessment products. In our design we employed loosely-tied distributed system architecture, strict modularity, test and simulation-based knowledge and skill assessment and an our original communications package called Communication Abstraction Layer (ComAL), specifically designed to support communication functions of e-learning systems in diverse network conditions (including offline environment and content aware networks).The system was tested in production environment on Faculty of Electronics, Telecommunications and Informatics, Technical University of Gdansk with great success, reducing staff workload and increasing efficiency of didactic process. The tests also showed system's versatility in classroom, remote and blended learning environments.
Concepts, Methodologies, Tools and Applications, 2010
Abstract In this article we propose a novel e-learning system, dedicated strictly to knowledge as... more Abstract In this article we propose a novel e-learning system, dedicated strictly to knowledge assessment tasks. In its functioning it utilizes web-based technologies, but its design differs radically from currently popular e-learning solutions which rely mostly on thin-client ...
CompEuro 1992 Proceedings Computer Systems and Software Engineering, 1992
[Conference Record] GLOBECOM '92 - Communications for Global Users: IEEE, 1992
An efficient and robust distributed protocol for packet radio LANs is presented. Called the coope... more An efficient and robust distributed protocol for packet radio LANs is presented. Called the cooperative random token (CRT) protocol, it is based on the concept of random reservation followed by explicit token passing. The protocol outperforms previous radio channel access protocols, while allowing for variable packet lengths and priorities and requiring no knowledge of the number, location, or identities of stations, no time slotting, and no network-wide feedback information about past transmissions. Station failures and/or transmission errors can be recovered from at the price of slight alterations to the original protocol. The results obtained via simulation suggest a high-speed radio LAN with Δ/T⩽0.1 and Δ/TR⩾5 as a preferred environment for the CRT protocol
Open Journal of Communications and Software, 2014
ABSTRACT The paper analyzes the problems of IPv4 to IPv6 migration processes and indicates the ar... more ABSTRACT The paper analyzes the problems of IPv4 to IPv6 migration processes and indicates the areas in which migration can be done without expensive replacement of hardware, software and organizational changes. This paper presents the migration tools developed for the SOHO network administrators. The tools provide theoretical knowledge and practical advices on migrating to IPv6 and enable automation of the migration process. The article presents basic problems encountered in migrating small networks environments to support IPv6. Problems were introduced along with proposals for migration methodologies and tools to assist in this process. The system supporting administrators with the IPv6 network migration was presented. The system consists of Migration Guide and Automated Migration Tool. They are interactive tools which allow the transmission of guidance on network migration.
2008 1st International Conference on Information Technology, 2008
Although Dynamic Host Configuration Protocol for IPv6 (DHCPv6) protocol was defined in 2003, it w... more Although Dynamic Host Configuration Protocol for IPv6 (DHCPv6) protocol was defined in 2003, it was designed as a framework rather than a complete solution to the automatic configuration in IPv6 networks. There are still some unsolved problems and new options yet to be defined. One example of such case is Fully Qualified Domain Name (FQDN) option, which final version has been published in late 2007. It describes DHCPv6 client and server behavior, but some important aspects remain unaddressed. Authors developed and released working open source implementation over a year before FQDN standard reached mature phase. This paper discuses those issues and recommends possible solutions. Another important development area in the DHCPv6 protocol is a lack of well defined authentication and authorization. Experimental AAA implementation has been developed and reached validation phase. Quick overview of the Dibbler project -a working, multi-platform, open-source DHCPv6 implementation -is also provided, its strengths, used solutions and validation methods used to prove its correctness are discussed. Conclusions and discussion regarding areas for further studies appears in the last section of this article.
Lecture Notes in Computer Science, 2010
IP networks are indispensable nowadays. They are among the most efficient platforms. The constant... more IP networks are indispensable nowadays. They are among the most efficient platforms. The constantly growing number of users and new services in these networks -the largest being the Internet -requires a good quality of any application used. Determining the QoS in real-time services is particularly important. This work is dedicated to exactly this aspect of the real-time service Video Telephony over IP (VToIP). First, the ITU-T standard H.323 for VToIP will be described and discussed briefly. Then, the performance of the H.263 codec in an ideal environment (without network impairments) will be analysed in detail. Following that, the performance of the codec H.263 with network impairments (packet loss being the main impairment factor) will be examined in detail. The paper finishes with a conclusion and an outlook.
2008 1st International Conference on Information Technology, 2008
Abstract This paper describes a system of geo-location of an IP user that would enable VoIP users... more Abstract This paper describes a system of geo-location of an IP user that would enable VoIP users to call 112. Basic requirement is fast (under 50 ms) determination of the commune of the subscriber. To obtain as accurate information as possible aggregation of several ...
Replacing the IPv4 protocol with IPv6 on the Internet is currently one of the aims of the Europea... more Replacing the IPv4 protocol with IPv6 on the Internet is currently one of the aims of the European Union policy. The main reason for this replacement is the effeteness of the addresses pool in the IPv4 protocol, which can cause serious complications in the evolution of the Internet and its adaptation in new areas, e.g., in next generation mobile telephony or the so called Internet of Things. Simultaneously, the addressing capabilities of the IPv6 protocol are practically unlimited and its new functionalities increase the attractiveness of its usage. The article discusses the problems connected with the IPv6 deployment on the Internet. Especially, the rules for realization of the IPv6 deployment and rules for cooperation of IPv4 with IPv6 (including cooperation tests) in network infrastructure and in applications are presented. Moreover, the European projects' results and the activity's directions of the national project Future Internet Engineering are discussed.
2011 IEEE/IPSJ International Symposium on Applications and the Internet, 2011
Abstract There are many reasons to deploy IPv6 protocol with IPv4 address space depletion being t... more Abstract There are many reasons to deploy IPv6 protocol with IPv4 address space depletion being the most indisputable. Unfortunately, migration to the IPv6 protocol seems slower than anticipated. To improve pace of the IPv6 deployment, authors of the article developed the ...
2010 Australasian Telecommunication Networks and Applications Conference, 2010
... Apr. 2010 [10] N. Moore, Optimistic Duplicate Address Detection (DAD) for IPv6, RFC 4429, I... more ... Apr. 2010 [10] N. Moore, Optimistic Duplicate Address Detection (DAD) for IPv6, RFC 4429, IETF, Apr. 2006. [11] S. Thomson, T. Narten, T.Jinmei IPv6 StatelessAddress Autoconfiguration, RFC 4862, IETF, Sep. 2007. [12 ...
Teletraffic Science and Engineering, 1994
Lecture Notes in Computer Science, 2004
Paper describes iSteering–a new method to control traffic in case of RPR network failure. There&a... more Paper describes iSteering–a new method to control traffic in case of RPR network failure. There's comparison of packet wrapping, steering and our proposed method iSteering, which can be used in case of transmitter/receiver or fiber failure. Numerical analysis for even and ...
Although Dynamic Host Configuration Protocol for IPv6 (DHCPv6) protocol was defined in 2003, it w... more Although Dynamic Host Configuration Protocol for IPv6 (DHCPv6) protocol was defined in 2003, it was designed as a framework rather than a complete solution to the automatic configuration in IPv6 networks. There are still some unsolved problems and new options yet to be defined. One example of such case is Fully Qualified Domain Name (FQDN) option, which final version has been published in late 2007. It describes DHCPv6 client and server behavior, but some important aspects remain unaddressed. Authors developed and released working open source implementation over a year before FQDN standard reached mature phase. This paper discuses those issues and recommends possible solutions. Another important development area in the DHCPv6 protocol is a lack of well defined authentication and authorization. Experimental AAA implementation has been developed and reached validation phase. Quick overview of the Dibbler project – a working, multi-platform, open-source DHCPv6 implementation – is also provided, its strengths, used solutions and validation methods used to prove its correctness are discussed. Conclusions and discussion regarding areas for further studies appears in the last section of this article.