Milivoj Simeonovski

Learn More
The Internet is built on top of intertwined network services, e.g., email, DNS, and content distribution networks operated by private or governmental organizations. Recent events have shown that these organizations may, knowingly or unknowingly, be part of global-scale security incidents including state-sponsored mass surveillance programs and large-scale(More)
A major disturbance for network providers in recent years have been Distributed Reflective Denial-of-Service (DRDoS) attacks. In such an attack, the adversary spoofs the IP address of a victim and sends a flood of tiny packets to vulnerable services. The services then respond to spoofed the IP, flooding the victim with large replies. Led by the idea that an(More)
Search engines are the prevalently used tools to collect information about individuals on the Internet. Search results typically comprise a variety of sources that contain personal information — either intentionally released by the person herself, or unintentionally leaked or published by third parties without being noticed, often with detrimental effects(More)
Many anonymous communication networks (ACNs) rely on routing traffic through a sequence of proxy nodes to obfuscate the originator of the traffic. Without an accountability mechanism, exit proxy nodes may become embroiled in a criminal investigation if originators commit criminal actions through the ACN. We present BackRef, a generic mechanism for ACNs that(More)
The management of identities on the Internet has evolved from the traditional approach (where each service provider stores and manages identities) to a federated identity management system (where the identity management is delegated to a set of identity providers). On the one hand, federated identity ensures usability and provides economic benefits to(More)
CAPTCHAs (Completely Automated Public Turing test to tell Computers and Humans Apart) are the dominantly used turing tests to protect websites against bots that are impersonating human users to gain access to various types of services. The test is designed in a way to be very difficult for robotic programs, but comfortably easy for humans. As artificial(More)
By its nature, the SMS communication is insecure and the message information can be viewed of many interested parties. Here we propose a protocol for secure SMS end-to-end communication between two mobile devices. Our protocol is based on a symmetric encryption of the message context and on secure key exchange. The security of our protocol is based on the(More)
By its nature, the SMS communication is insecure and the message information can be viewed of many interested parties. Here we propose a protocol for secure SMS end-to-end communication between two mobile devices. Our protocol is based on a symmetric encryption of the message context. The encryption is defined by using quasigroup transformations. We have(More)
Many anonymous communication (AC) networks rely on routing traffic through proxy nodes to obfuscate the originator of the traffic. Without an accountability mechanism, exit proxy nodes risk sanctions by law enforcement if users commit illegal actions through the AC network. We present BACKREF, a generic mechanism for AC networks that provides practical(More)
The Internet has undergone dramatic changes in the past 15 years, and now forms a global communication platform that billions of users rely on for their daily activities. While this transformation has brought tremendous benefits to society, it has also created new threats to online privacy, ranging from profiling of users for monetizing personal information(More)
  • 1