Asymptotic Analysis of Plausible Tree Hash Modes for SHA-3
This work addresses the standardization challenge for tree hash modes in SHA-3, which is incremental as it builds on prior proposals to improve resource usage across diverse systems.
The paper tackles the problem of selecting a tree hash mode for SHA-3 standardization by reviewing existing modes, identifying issues, and proposing new modes tailored to different device categories and specifications, analyzing their asymptotic behavior.
Discussions about the choice of a tree hash mode of operation for a standardization have recently been undertaken. It appears that a single tree mode cannot address adequately all possible uses and specifications of a system. In this paper, we review the tree modes which have been proposed, we discuss their problems and propose remedies. We make the reasonable assumption that communicating systems have different specifications and that software applications are of different types (securing stored content or live-streamed content). Finally, we propose new modes of operation that address the resource usage problem for the three most representative categories of devices and we analyse their asymptotic behavior.