k-Degree anonymity on directed networks

  • Jordi Casas-RomaEmail author
  • Julián Salas
  • Fragkiskos D. Malliaros
  • Michalis Vazirgiannis
Regular Paper


In this paper, we consider the problem of anonymization on directed networks. Although there are several anonymization methods for networks, most of them have explicitly been designed to work with undirected networks and they cannot be straightforwardly applied when they are directed. Moreover, ignoring the direction of the edges causes important information loss on the anonymized networks in the best case. In the worst case, the direction of the edges may be used for reidentification, if it is not considered in the anonymization process. Here, we propose two different models for k-degree anonymity on directed networks, and we also present algorithms to fulfill these k-degree anonymity models. Given a network G, we construct a k-degree anonymous network by the minimum number of edge additions. Our algorithms use multivariate micro-aggregation to anonymize the degree sequence, and then, they modify the graph structure to meet the k-degree anonymous sequence. We apply our algorithms to several real datasets and demonstrate their efficiency and practical utility.


Anonymity Social networks Directed networks Data utility Privacy 



Jordi Casas-Roma was partially supported by the Spanish MCYT and the FEDER funds under Grants TIN2011-27076-C03 “CO-PRIVACY” and TIN2014-57364-C2-2-R “SMARTGLACIS”. Julián Salas acknowledges the support of a UOC postdoctoral fellowship and TIN2014-57364-C2-2-R “SMARTGLACIS”.


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Copyright information

© Springer-Verlag London Ltd., part of Springer Nature 2018

Authors and Affiliations

  1. 1.Faculty of Computer Science, Multimedia and TelecommunicationsUniversitat Oberta de Catalunya (UOC)BarcelonaSpain
  2. 2.Internet Interdisciplinary Institute (IN3)Universitat Oberta de Catalunya (UOC)CastelldefelsSpain
  3. 3.Center for Cybersecurity Research of Catalonia (CYBERCAT)BarcelonaSpain
  4. 4.CentraleSupélec, University of Paris-SaclayGif-sur-YvetteFrance
  5. 5.Inria SaclayPalaiseauFrance
  6. 6.École PolytechniquePalaiseauFrance
  7. 7.Athens University of Economics and BusinessAthensGreece

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