Wang, Z., Klaiber, M., Gera, Y., Simon, S., Richter, T.: Fast lossless image compression with 2D Golomb parameter adaptation based on JPEG-LS. In: Signal Processing Conference (EUSIPCO), 2012 Proceedings of the 20th European. pp. 1920–1924 (2012).
Zusammenfassung
A Fast and Lossless Image Compression (FLIC) algorithm based on the median edge predictor and Golomb coder of JPEG-LS is presented. FLIC eliminates the gradient-based context model from the JPEG-LS standard, the most expensive parts with respect to computational complexity and memory space requirements. To avoid a large context memory, Golomb parameter is selected based on the coding states and the prediction residuals of up to two immediate neighbors, one in each dimension. The FLIC algorithm has low memory footprint and dissolves the data dependencies in JPEG-LS to facilitate parallelization. Experimental results show that the FLIC algorithm achieves a throughput speedup factor of 3.7 over JPEG-LS with less than 4% compression performance penalty. Lossless compression performance results further show that FLIC outperforms other state-of-the-art standards including JPEG 2000 and JPEG XR.BibTeX
Richter, Th., Rudlof, S., Boehringer, D., Grüninger, Ch., Helmig, R., Rohde, Ch., Bernlohr, H., Munz, C.-D., Stock, A.: ViPLab - A Virtual Programming Laboratory for Mathematics and Engineering. In: SEFI 40th annual conference (2012).
Zusammenfassung
In the process of the implementation of the eBologna program of the European
states and the recent change of the German university system from the
Diploma to the Bachelor/Master system, studies at German universities have
been redesigned; courses have been condensed and learning content has been
re-structured into granular modules, each of which requires an
evaluation at the end of the semester. Simultaneously, the skills required
for working in research and development changed as well; handling of computer software,
knowledge of mathematical or numerical algorithms and programming skills
play an increasingly important role in the daily job routine of the working
engineer. To support learning by practical exercises, engineering faculties,
the faculties of mathematics and physics, and the Computing Center of the
University of Stuttgart setup a project for implementing an online
programming lab for teaching the required skills. The focus of this project
is to provide easy access to the necessary software tools, avoid the
overhead of installation and maintenance, and seamlessly integrate these
tools into the eLearning infrastructure of the university. This paper
describes the motivation and backgrounds, the software infrastructure and
early results of this project.BibTeX
Vensmer, A., Kiesel, S.: DynFire: Dynamic Firewalling in Heterogeneous Environments. In: Proceedings of the World Congress on Internet Security (WorldCIS-2012). , Guleph, Canada (2012).
Zusammenfassung
This paper presents ``DynFire,'' a novel approach for the
role-based, dynamic control of network firewalls. DynFire
allows an individually controlled, secure access to the IT
resources of a large organization, with particular focus on
mobile users and users with restricted rights, such as
subcontractors. The basic assumption behind DynFire is that,
within a secured network domain separated from the Internet,
we can establish a temporary binding between an IP address
and a single user ID. Whenever a user connects to or
disconnects from this secure network domain, firewalls are
configured accordingly, using a centralized ``Firewall
Manager'' and standardized signaling protocols.BibTeX
Richter, T., Simon, S.: On the JPEG 2000 Ultrafast Mode. In: 2012 IEEE International Conference on Image Processing ICIP 2012. pp. 2501–2504. IEEE, Lake Buena Vista, Florida, USA (2012).
https://doi.org/10.1109/ICIP.2012.6467406.
Zusammenfassung
Recently, the JPEG committee discussed the introduction of an ``ultrafast'' mode for JPEG 2000 encoding. This considered extension of the JPEG 2000 framework replaces the EBCOT coding by a combined Huffman-Runlength code, and adds an optional additional prediction step after quantization. While the resulting codec is not compatible with existing JPEG 2000, it still allows lossless transcoding from JPEG 2000 and back, and performance measurements show that it offers nearly the quality of JPEG 2000 and similar quality than JPEG XR at a much lower complexity comparable to the complexity of the IJG JPEG software. This work introduces the extension, and compares its performance with other JPEG standards and other extensions of JPEG 2000 currently under standardization.BibTeX
D.Lamp, S.Berger, M.Stein, T.Voith, T.Cucinotta, M.Bertogna: Execution and Resource Management in QoS-Aware Virtualized Infrastructures. In: Achieving Real-Time in Distributed Computing: From Grids to Clouds: IGI Global. pp. 200–217 (2012).
BibTeX
(Editor), S.K., Previdi, S., Stiemerling, M., Woundy, R., Yang, Y.R.: Application-Layer Traffic Optimization (ALTO) Requirements. RFC Editor (2012).
https://doi.org/10.17487/RFC6708.
Zusammenfassung
Many Internet applications are used to access resources, such as
pieces of information or server processes that are available in several
equivalent replicas on different hosts. This includes, but is not limited
to, peer-to-peer file sharing applications. The goal of Application-Layer
Traffic Optimization (ALTO) is to provide guidance to applications that
have to select one or several hosts from a set of candidates capable of
providing a desired resource. This guidance shall be based on parameters
that affect performance and efficiency of the data transmission between
the hosts, e.g., the topological distance. The ultimate goal is to improve
performance or Quality of Experience in the application while reducing the
utilization of the underlying network infrastructure.
This document enumerates requirements for specifying, assessing, or
comparing protocols and implementations.BibTeX
Berger, S., Vensmer, A., Kiesel, S.: An ABAC-based Policy Framework for Dynamic Firewalling. In: Proceedings of the The Seventh International Conference on Systems and Networks Communications (ICSNC 2012). pp. 118-- 123. , Lisbon, Portugal (2012).
Zusammenfassung
This paper presents the Policy Framework of DynFire,
a novel approach for attribute-based, dynamic control
of network firewalls. DynFire allows an individually
controlled, secure access to IT resources of a large
organization, with particular focus on mobile users and
users with restricted rights, such as subcontractors.
The basic assumption behind DynFire is that, within a
secured network domain separated from the Internet, a
temporary binding between an IP address and a single user
ID can be established. Users with different attributes can
authenticate to the network and get individual access to
network resources. To administrate such a large amount of
users and different access rights within a secured network
domain of an organization, which includes distributed
organisational zones, a policy framework is needed. The
following paper presents a policy framework for dynamic
and distributed firewalls which is able to grant access
control on a per-user basis, with multitenancy capabilities
and administrative delegation.BibTeX
Richter, T.: Compressing JPEG 2000 JPIP Cache State Information. In: Marcellin, J.A.S.M.W. (ed.) Data Compression Conference (DCC), 2012. pp. 13–21. IEEE, Snowbird, Utah, USA (2012).
https://doi.org/10.1109/DCC.2012.9.
Zusammenfassung
JPEG 2000 part 9, or short JPIP, is an interactive image browsing protocol that allows the selective delivery of image regions, components or scales from JPEG 2000 image. Typical applications are browsing tools for medical databases where transmitting huge images from server to client in total would be uneconomical. Instead, JPIP allows extracting only the desired image parts for analysis by an http type request syntax. Such a JPIP connection may either operate in a session within which the server remains aware of the image data already cached at the client and it hence doesn't have to transmit again, or it may operate in a stateless mode in which the server has no model of the data already available on the client. In such cases, the client may include a description of its cache model within a proceeding request to avoid retransmission of data already buffered. Unfortunately, the standard defined methods how such cache models are described are very inefficient, and a single request including a cache model may grow several KBytes large for typical images and requests, making the deployment of a JPIP server on top of existing http server infrastructure rather inconvenient. In this work, a lossy and loss less embedded compression scheme for such JPIP cache model adjustment requests based on a modified zero-tree algorithm is proposed, this algorithm works even in constraint environments where request size must remain limited. The proposed algorithm losslessly compresses such cache model adjustment requests often better than by a factor of 1:8, but may even perform a 1:8000 compression in cases where the cache model has to describe a large number of precincts.BibTeX
Richter, Th., Grube, P., Zutin, D.: A Standardized Metadata Set for Annotation of Virtual and Remote Laboratories. In: 2012 IEEE International Symposium on Multimedia ISM 2012. pp. 451–456. IEEE, Irvine, California, USA (2012).
https://doi.org/10.1109/ISM.2012.92.
Zusammenfassung
Online Laboratories and Virtual Experiments start to play an increasingly important role in the education of Engineering and Science Education. While several repositories for online and virtual experiments are available, a common method for annotating experiments to simplify their discovery is not yet available and accepted. In 2010, an international group of online lab providers formed the Global Online Lab Consortium (GOLC) to address the issues of interoperability between online laboratories and laboratory compilations, one of its activities is the establishment of an ontology and a common metadata set that addresses not only the needs of typical lab providers and lab users, but also of storage and archival institutions such as libraries. This article describes the current status of the GOLC activities in the metadata subcommittee, lists the requirements of various user groups of the metadata set and provides insight into both the underlying ontology and the metadata specifications themselves.BibTeX
Berger, S., Vensmer, A., Kiesel, S.: An ABAC-based Policy Framework for Dynamic Firewalling. In: Proceedings of the The Seventh International Conference on Systems and Networks Communications (ICSNC 2012). pp. 118--123. , Lisbon, Portugal (2012).
Zusammenfassung
This paper presents the Policy Framework of DynFire,
a novel approach for attribute-based, dynamic control
of network firewalls. DynFire allows an individually
controlled, secure access to IT resources of a large
organization, with particular focus on mobile users and
users with restricted rights, such as subcontractors.
The basic assumption behind DynFire is that, within a
secured network domain separated from the Internet, a
temporary binding between an IP address and a single user
ID can be established. Users with different attributes can
authenticate to the network and get individual access to
network resources. To administrate such a large amount of
users and different access rights within a secured network
domain of an organization, which includes distributed
organisational zones, a policy framework is needed. The
following paper presents a policy framework for dynamic
and distributed firewalls which is able to grant access
control on a per-user basis, with multitenancy capabilities
and administrative delegation.BibTeX
Kiesel, S.: VoIPUS: IP-Telefonie für die Universität Stuttgart, (2012).
BibTeX
Gera, Y., Wang, Z., Simon, S., Richter, T.: Fast and Context-free Lossless Image Compression Algorithm based on JPEG-LS. In: Marcellin, J.A.S.M.W. (ed.) Data Compression Conference (DCC), 2012. IEEE, Snowbird, Utah, USA (2012).
https://doi.org/10.1109/DCC.2012.64.
Zusammenfassung
While the context-based entropy coding and bias cancellation steps in the JPEG-LS standard are key features to its compression performance, these steps also enlarge the memory footprint, create dependencies in the data path of implementations and hence limit parallelism in modern multi-core or GPU architectures, and the throughput in hardware implementations. In the proposed modification of JPEG-LS, such most expensive parts with respect to memory space requirements and computational complexity are omitted.BibTeX
Wang, Z., Chanda, D., Simon, S., Richter, T.: Memory efficient lossless compression of image sequences with JPEG-LS and temporal prediction. In: Picture Coding Symposium (PCS), 2012. pp. 305–308 (2012).
https://doi.org/10.1109/PCS.2012.6213353.
Zusammenfassung
In this paper, a lossless encoder for image sequences based on JPEG-LS defined for still images with temporal-extended prediction and context modeling is proposed. As embedded systems are one important field of application of the codec, on-line lossy reference frame compression is used to reduce the encoder's memory requirement. Variations of the pixel values in the reference frame due to lossy compression are acceptable since the predictor provides only estimations of the pixel values being encoded in the current frame. Larger variations decrease the final lossless compression performance of the encoder such that a trade-off between the memory requirement and the overall compression ratio is required. Different compression algorithms for the reference frame, including JPEG, JPEG 2000 and near-lossless JPEG-LS, and their impacts on the memory requirement and the overall lossless compression ratio have been studied. Experimental results show 9.6% or more gain in lossless compression ratio compared to applying the standard JPEG-LS frame-by-frame and 80% reduction in the encoder buffer size compared to storing the uncompressed reference frame.BibTeX
Marx, R., Kiesel, S.: Dynamic firewalling for femto-cell communication, (2012).
Zusammenfassung
Application scenarios for femto cells (aka Home (e)Node Bs)
constantly grew since their first specification in 3GPP
Release 8. However, the deployment of femto cells is
challenging for network operators as femto cells get direct
access to the core network via a VPN tunnel. Moreover, the
femto cells' integrity cannot be guaranteed because they are
operated outside of the operator's domain. Thus, it
enormously increases security if the access within
the core network is limited by setting user-dependent
firewalling rules to allowed services. Configuration effort
can be eased by employing a dynamic firewalling approach,
which supports setting firewall rules on-demand on a
per-user basis.
This talk will present the dynamic firewalling apporach
developed in the DynFire project. DynFire allows an
individually controlled, secure access to the IT resources
of a large organization, with particular focus on mobile
users and users with restricted rights.BibTeX
Vensmer, A., Kiesel, S.: DynFire: Dynamic Firewalling in Heterogeneous Environments. In: Proceedings of the World Congress on Internet Security (WorldCIS-2012). , Guleph, Canada (2012).
Zusammenfassung
This paper presents ``DynFire,'' a novel approach for the
role-based, dynamic control of network firewalls. DynFire
allows an individually controlled, secure access to the IT
resources of a large organization, with particular focus on
mobile users and users with restricted rights, such as
subcontractors. The basic assumption behind DynFire is that,
within a secured network domain separated from the Internet,
we can establish a temporary binding between an IP address
and a single user ID. Whenever a user connects to or
disconnects from this secure network domain, firewalls are
configured accordingly, using a centralized ``Firewall
Manager'' and standardized signaling protocols.BibTeX
Richter, T., Simon, S.: Towards high-speed, low-complexity image coding: Variants and modification of JPEG 2000. In: Tescher, A.G. (ed.) Applications of Digital Image Processing XXXV. p. 10. SPIE (2012).
https://doi.org/10.1117/12.928173.
Zusammenfassung
Recently, the JPEG committee discussed the introduction of an ültrafast" mode for JPEG 2000 encoding. This considered extension of the JPEG 2000 framework replaces the EBCOT coding by a combined Human- Runlength code, and adds an optional additional prediction step after quantization. While the resulting codec is not compatible with existing JPEG 2000, it still allows lossless transcoding from JPEG 2000 and back, and performance measurements show that it offers nearly the quality of JPEG 2000 and similar quality than JPEG XR at a much lower complexity comparable to the complexity of the IJG JPEG software. This work introduces the extension, and compares its performance with other JPEG standards and other extensions of JPEG 2000 currently under standardization.BibTeX
M.Stein, K.Oberle, T.Voith, D.Lamp, S.Berger: Network Management in Virtualized Infrastructures. In: Achieving Real-Time in Distributed Computing: From Grids to Clouds: IGI Global. pp. 218–235 (2012).
BibTeX
Cucinotta, T., Checconi, F., Kousiouris, G., Konstanteli, K., Gogouvitis, S.V., Kyriazis, D., Varvarigou, T.A., Mazzetti, A., Zlatev, Z., Papay, J., Boniface, M., Berger, S., Lamp, D., Voith, T., Stein, M.: Virtualised e-Learning on the IRMOS real-time Cloud. Service Oriented Computing and Applications. 6, 151–166 (2012).
BibTeX
Richter, T., Watson, R., Kassavetis, S., Kraft, M., Grube, P., Boehringer, D., de Vries, P., Hatzikraniotis, E., Logothetidis, S.: The WebLabs of the University of Cambridge: A study of securing remote instrumentation. In: 9th International Conference on Remote Engineering and Virtual Instrumentation (REV). pp. 1–5. IEEE, Bilbao, Spain (2012).
https://doi.org/10.1109/REV.2012.6293099.
Zusammenfassung
Safe deployment of web interfaces for remote instrumentation requires that the laboratory system be protected from harmful manipulation by end users or attacks from malicious software over the internet. Industrial control systems, although highly relevant to contemporary engineering education and an essential component of many remote experiments, are typically only designed to run in a secured local area network and cannot safely be exposed to the internet because they lack a sufficiently robust security infrastructure. They also typically require the installation of proprietary software on the end user system which is an obstacle for deployment in learning scenarios at universities. Facing these challenges when bringing the Chemical Engineering WebLabs at the University of Cambridge online, the Computing Center of the University of Stuttgart and the University of Cambridge developed a framework to allow the secure deployment of industrial controller software in remote learning applications; this framework is generic, has a low-barrier for students as it only requires an internet browser and Java$^\mboxTM$ installation, and it satisfies the high security demands of most university infrastructure providers. Furthermore, the framework has the potential to be applied to almost any remote laboratory setup and is compatible with all commonly-used operating systems at the user end.BibTeX
Kiesel, S., Stiemerling, M.: 3rd Party ALTO Server Discovery (3pdisc). IETF Secretariat (2012).
Zusammenfassung
The goal of Application-Layer Traffic Optimization (ALTO) is to
provide guidance to applications, which have to select one or several
hosts from a set of candidates that are able to provide a desired
resource.
Entities seeking guidance need to discover and possibly select an
ALTO server to ask. This is called ALTO server discovery. This memo
describes an ALTO server discovery mechanism for a 3rd party setting,
i.e., where the ALTO client is not co-located with the actual
resource consumer.BibTeX
Zusammenfassung
Application scenarios for femto cells (aka Home (e)Node Bs)
constantly grew since their first specification in 3GPP
Release 8. However, the deployment of femto cells is
challenging for network operators as femto cells get direct
access to the core network via a VPN tunnel. Moreover, the
femto cells' integrity cannot be guaranteed because they are
operated outside of the operator's domain. Thus, it
enormously increases security if the access within
the core network is limited by setting user-dependent
firewalling rules to allowed services. Configuration effort
can be eased by employing a dynamic firewalling approach,
which supports setting firewall rules on-demand on a
per-user basis.
This talk will present the dynamic firewalling apporach
developed in the DynFire project. DynFire allows an
individually controlled, secure access to the IT resources
of a large organization, with particular focus on mobile
users and users with restricted rights.BibTeX
Kiesel, S.: VoIPUS: IP-Telefonie für die Universität Stuttgart, (2012).
BibTeX
Kiesel, S. (Editor), Previdi, S., Stiemerling, M., Woundy, R., Yang, Y.R.: Application-Layer Traffic Optimization (ALTO) Requirements. RFC Editor (2012).
https://doi.org/10.17487/RFC6708.
Zusammenfassung
Many Internet applications are used to access resources, such as
pieces of information or server processes that are available in several
equivalent replicas on different hosts. This includes, but is not limited
to, peer-to-peer file sharing applications. The goal of Application-Layer
Traffic Optimization (ALTO) is to provide guidance to applications that
have to select one or several hosts from a set of candidates capable of
providing a desired resource. This guidance shall be based on parameters
that affect performance and efficiency of the data transmission between
the hosts, e.g., the topological distance. The ultimate goal is to improve
performance or Quality of Experience in the application while reducing the
utilization of the underlying network infrastructure.
This document enumerates requirements for specifying, assessing, or
comparing protocols and implementations.BibTeX