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Secure Multicast in a WAN

Dahlia Malkhi·Michael Merritt·Ohad Rodeh
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Abstract

A secure reliable multicast protocol enables a process to send a message to a group of recipients such that all correct destinations receive the same message, despite the malicious efforts of fewer than a third of the total number of processes, including the sender. This has been sh own to be a useful tool in building secure distributed services, albeit with a cost that typically grows linearly with the size of the system. For very large networks, for which this is prohibitive, we present two approaches for reducing the cost: First, we show a protocol whose cost is on the order of the number of tolerated failures. Secondly, we show how relaxing the consistency requirement to a probabilistic guarantee can reduce the associated cost, effectively to a constant.

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Dahlia Malkhi, Michael Merritt, Ohad Rodeh. 1999-08-12. Secure Multicast in a WAN. https://arxiv.org/abs/cs/9908008

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