• The last hop of global notification delivery to mobile users. Matching preferences, context, and device constraints. 

      Zagorodnov, Dmitrii; Johansen, Dag (Research report; Forskningsrapport, 2004)
      Events injected by publishers into a publish/subscribe system may reach users through a variety of devices: a stationary desktop, a laptop, a mobile phone, etc. We argue that the "last hop" -- from the network to the output device -- has unique properties, owing to the mobile nature of these devices, and as such demands special consideration. In particular, user's preferences and location may limit ...
    • Minimizing unwanted traffic in a global messaging system. Spam, denial-of-service-attacks, and edacious subscribers 

      Zagorodnov, Dmitrii (Research report; Forskningsrapport, 2005)
      The main purpose of this paper is to illuminate two types of unwanted traffic in a publish/subscribe system -- malicious (spam, DoS attacks) and vain (unused events) -- and suggest a general mechanism for minimizing their effects. We do this by augmenting the classic publish/subscribe interface with volume-limiting parameters -- a combination of attributes assigned to events by publishers and ...
    • Policies and metrics for fair resource sharing 

      Renesse, Robbert van; Kvalnes, Aage; Zagorodnov, Dmitrii; Johansen, Dag (Research report; Forskningsrapport, 2006)
      Performance isolation is essential to operating systems shared by dependable services. Unfortunately, most such systems, including real-time operating systems and VMMs, only fairly divide and account for CPU cycles. We submit that dependable services require specifying and enforcing policies for all resources, and that current metrics for evaluating fair sharing are insufficient. This paper proposes ...
    • Practical and low-overhead masking of failures of TCP-based servers 

      Marzullo, Keith; Zagorodnov, Dmitrii; Alvisi, Lorenzo; Bressoud, Thomas C. (Research report; Forskningsrapport, 2005-08-25)
      This article describes an architecture that allows a replicated service to survive crashes without breaking its TCP connections. Our approach does not require modifications to the TCP protocol, to the operating system on the server, or to any of the software running on the clients. Furthermore, it runs on commodity hardware. We compare two implementations of this architecture – one based on ...