Paper 2016/466

AnNotify: A Private Notification Service

Ania Piotrowska, Jamie Hayes, Nethanel Gelernter, George Danezis, and Amir Herzberg


AnNotify is a scalable service for private, timely and low-cost online notifications, based on anonymous communication, sharding, dummy queries, and Bloom filters. We present the design and analysis of AnNotify, as well as an evaluation of its costs. We outline the design of AnNotify and calculate the concrete advantage of an adversary observing multiple queries. We present a number of extensions, such as generic presence and broadcast notifications, and applications, including notifications for incoming messages in anonymous communications, updates to private cached web and Domain Name Service (DNS) queries.

Note: Minor updates in the paper and more clear descriptions added.

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Publication info
Preprint. MAJOR revision.
private notificationsBloom filtersdifferential privacymix networks
Contact author(s)
anna piotrowska 15 @ ucl ac uk
2017-11-06: last of 5 revisions
2016-05-13: received
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      author = {Ania Piotrowska and Jamie Hayes and Nethanel Gelernter and George Danezis and Amir Herzberg},
      title = {AnNotify: A Private Notification Service},
      howpublished = {Cryptology ePrint Archive, Paper 2016/466},
      year = {2016},
      note = {\url{}},
      url = {}
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