Comments on “mabs multicast authentication based on batch signature”

1. Comments on “MABS: Multicast Authentication Based on Batch Signature”
Recently, Zhou et al. proposed a multicast authentication protocol named MABS employing an
efficient cryptographic primitive called batch verification to authenticate arbitrary number of
data packets simultaneously, and three implementations were presented: MABS-RSA, MABS-
BLS, and MABS-DSA. In this letter, we are concerned with the last implementation, which is
claimed to be much more efficient than the others. Our particular interest also lies in that MABS-
DSA was designed to thwart a known attack against its underlying batch DSA primitive and is
claimed to be with increased security. After a careful revisit of the involved arithmetic, however,
we find that the real issue lies in protocol correctness rather than security; the algorithm of
MABS-DSA actually does not hold as one would expect. More specifically, even if each of the
data packets has been signed by an honest sender and securely delivered to the receiver,
verification of the batch of signatures will still fail almost always.
Ambit lick Solutions
Mail Id: Ambitlick@gmail.com , Ambitlicksolutions@gmail.Com