@inproceedings{4344, author = {{Blömer, Johannes and Brauer, Sascha and Bujna, Kathrin}}, booktitle = {{29th International Symposium on Algorithms and Computation (ISAAC 2018)}}, isbn = {{978-3-95977-094-1}}, location = {{Jiaoxi, Yilan County, Taiwan}}, pages = {{46:1----46:12}}, publisher = {{Schloss Dagstuhl--Leibniz-Zentrum fuer Informatik}}, title = {{{Coresets for Fuzzy K-Means with Applications}}}, doi = {{10.4230/LIPIcs.ISAAC.2018.46}}, year = {{2018}}, } @misc{5426, author = {{von Heißen, Oliver}}, title = {{{Implementierung und Analyse von Searchable Encryption}}}, year = {{2018}}, } @phdthesis{6597, author = {{Juhnke, Jakob}}, publisher = {{Universität Paderborn}}, title = {{{Models and Constructions for Secure Reputation Systems}}}, doi = {{10.17619/UNIPB/1-570}}, year = {{2018}}, } @inproceedings{3873, author = {{Blömer, Johannes and Eidens, Fabian and Juhnke, Jakob}}, booktitle = {{The International Conference on Cryptology And Network Security (CANS)}}, isbn = {{978-3-030-00434-7}}, location = {{Naples, Italy}}, pages = {{235--255}}, publisher = {{Springer}}, title = {{{Enhanced Security of Attribute-Based Signatures}}}, doi = {{10.1007/978-3-030-00434-7_12}}, volume = {{11124}}, year = {{2018}}, } @inproceedings{2379, abstract = {{In this paper, we introduce the notion of delegatable attribute-based anonymous credentials (DAAC). Such systems offer fine-grained anonymous access control and they give the credential holder the ability to issue more restricted credentials to other users. In our model, credentials are parameterized with attributes that (1) express what the credential holder himself has been certified and (2) define which attributes he may issue to others. Furthermore, we present a practical construction of DAAC. For this construction, we deviate from the usual approach of embedding a certificate chain in the credential. Instead, we introduce a novel approach for which we identify a new primitive we call dynamically malleable signatures (DMS) as the main ingredient. This primitive may be of independent interest. We also give a first instantiation of DMS with efficient protocols. }}, author = {{Blömer, Johannes and Bobolz, Jan}}, booktitle = {{ACNS 2018 Applied Cryptography & Network security}}, location = {{Leuven, Belgium}}, title = {{{Delegatable Attribute-based Anonymous Credentials from Dynamically Malleable Signatures}}}, doi = {{10.1007/978-3-319-93387-0_12}}, year = {{2018}}, } @phdthesis{2908, author = {{Bujna, Kathrin}}, publisher = {{Universität Paderborn}}, title = {{{Soft Clustering Algorithms - Theoretical and Practical Improvements}}}, doi = {{10.17619/UNIPB/1-226}}, year = {{2017}}, } @inproceedings{2967, author = {{Blömer, Johannes and Liske, Gennadij}}, booktitle = {{Proceedings of the International Conference of Mathematical Aspects of Computer and Information Sciences (MACIS)}}, isbn = {{9783319724522}}, issn = {{0302-9743}}, pages = {{438--453}}, publisher = {{Springer International Publishing}}, title = {{{Subtleties in Security Definitions for Predicate Encryption with Public Index}}}, doi = {{10.1007/978-3-319-72453-9_35}}, volume = {{10693}}, year = {{2017}}, } @phdthesis{116, author = {{Liske, Gennadij}}, publisher = {{Universität Paderborn}}, title = {{{CCA-Security for Predicate Encryption Schemes}}}, doi = {{10.17619/UNIPB/1-220}}, year = {{2017}}, } @inproceedings{2343, author = {{Löken, Nils}}, booktitle = {{Proceedings of the 12th International Conference on Availability, Reliability and Security - ARES '17}}, isbn = {{9781450352574}}, publisher = {{ACM Press}}, title = {{{Searchable Encryption with Access Control}}}, doi = {{10.1145/3098954.3098987}}, year = {{2017}}, } @inproceedings{2344, author = {{Blömer, Johannes and Günther, Peter and Krummel, Volker and Löken, Nils}}, booktitle = {{Foundations and Practice of Security}}, isbn = {{9783319756493}}, issn = {{0302-9743}}, pages = {{3--17}}, publisher = {{Springer International Publishing}}, title = {{{Attribute-Based Encryption as a Service for Access Control in Large-Scale Organizations}}}, doi = {{10.1007/978-3-319-75650-9_1}}, year = {{2017}}, } @inbook{2381, abstract = {{Metric facility location and K-means are well-known problems of combinatorial optimization. Both admit a fairly simple heuristic called single-swap, which adds, drops or swaps open facilities until it reaches a local optimum. For both problems, it is known that this algorithm produces a solution that is at most a constant factor worse than the respective global optimum. In this paper, we show that single-swap applied to the weighted metric uncapacitated facility location and weighted discrete K-means problem is tightly PLS-complete and hence has exponential worst-case running time.}}, author = {{Brauer, Sascha}}, booktitle = {{Lecture Notes in Computer Science}}, editor = {{Fotakis, Dimitris and Pagourtzis, Aris and Paschos, Vangelis Th.}}, isbn = {{9783319575858}}, issn = {{0302-9743}}, location = {{Athens, Greece}}, pages = {{116--127}}, publisher = {{Springer International Publishing}}, title = {{{Complexity of Single-Swap Heuristics for Metric Facility Location and Related Problems}}}, doi = {{10.1007/978-3-319-57586-5_11}}, volume = {{10236}}, year = {{2017}}, } @misc{60, author = {{Niehus, David}}, publisher = {{Universität Paderborn}}, title = {{{Semantically Secure Attribute-based Searchable Encryption}}}, year = {{2017}}, } @misc{88, author = {{Ganesh Athreya, Advait}}, publisher = {{Universität Paderborn}}, title = {{{Instantiating a Predicate Encryption Scheme via Pair Encodings}}}, year = {{2017}}, } @misc{67, author = {{Jürgens, Mirko}}, publisher = {{Universität Paderborn}}, title = {{{Provably Secure Key-Derivation-Functions for Certain Types of Applications}}}, year = {{2017}}, } @misc{104, author = {{Diemert, Denis}}, publisher = {{Universität Paderborn}}, title = {{{EAX - An Authenticated Encryption Mode for Block Ciphers}}}, year = {{2017}}, } @misc{117, author = {{Bemmann, Pascal}}, publisher = {{Universität Paderborn}}, title = {{{Attribute-based Signatures using Structure Preserving Signatures}}}, year = {{2017}}, } @misc{2898, author = {{Weis, Eduard}}, title = {{{Searchable Encryption}}}, year = {{2016}}, } @inproceedings{2947, author = {{Blömer, Johannes and Günther, Peter}}, booktitle = {{2015 Workshop on Fault Diagnosis and Tolerance in Cryptography (FDTC)}}, isbn = {{9781467375795}}, publisher = {{IEEE}}, title = {{{Singular Curve Point Decompression Attack}}}, doi = {{10.1109/fdtc.2015.17}}, year = {{2016}}, } @inbook{2948, author = {{Günther, Peter and Krummel, Volker}}, booktitle = {{Mathematical Aspects of Computer and Information Sciences}}, isbn = {{9783319328584}}, issn = {{0302-9743}}, pages = {{151--165}}, publisher = {{Springer International Publishing}}, title = {{{Implementing Cryptographic Pairings on Accumulator Based Smart Card Architectures}}}, doi = {{10.1007/978-3-319-32859-1_13}}, year = {{2016}}, } @inbook{2968, author = {{Blömer, Johannes and Lammersen, Christiane and Schmidt, Melanie and Sohler, Christian}}, booktitle = {{Algorithm Engineering}}, isbn = {{9783319494869}}, issn = {{0302-9743}}, pages = {{81--116}}, publisher = {{Springer International Publishing}}, title = {{{Theoretical Analysis of the k-Means Algorithm – A Survey}}}, doi = {{10.1007/978-3-319-49487-6_3}}, year = {{2016}}, }