FORCING OUT A CONFESSION - Threshold Discernible Ring Signatures

Swarun Kumar, Shivank Agrawal, Ramarathnam Venkatesan, Satya Lokam, C. Pandu Rangan


Ring signature schemes (Rivest et al., 2001) enable a signer to sign a message and remain hidden within an arbitrary group A of n people, called a ring. The signer may choose this ring arbitrarily without any setup procedure or the consent of anyone in A. Among several variations of the notion, step out ring signatures introduced in (Klonowski et al., 2008) address the issue of a ring member proving that she is not the original signer of a message, in case of dispute. First we show that the scheme in (Klonowski et al., 2008) has several flaws and design a correct scheme and prove formally the security of the same. Then we use the basic constructs of our scheme to design a protocol for a new problem, which we refer to as threshold discernible ring signatures. In threshold discernible ring signatures, a group B of t members can co-operate to identify the original signer of a ring signature that involved a group A of n alleged signers, where B ⊂ A and n >t. This is the first time that this problem is considered in the literature and we formally prove the security of our novel scheme in the random oracle model.


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Paper Citation

in Harvard Style

Kumar S., Agrawal S., Venkatesan R., Lokam S. and Pandu Rangan C. (2010). FORCING OUT A CONFESSION - Threshold Discernible Ring Signatures . In Proceedings of the International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2010) ISBN 978-989-8425-18-8, pages 379-388. DOI: 10.5220/0002984203790388

in Bibtex Style

author={Swarun Kumar and Shivank Agrawal and Ramarathnam Venkatesan and Satya Lokam and C. Pandu Rangan},
title={FORCING OUT A CONFESSION - Threshold Discernible Ring Signatures},
booktitle={Proceedings of the International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2010)},

in EndNote Style

JO - Proceedings of the International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2010)
TI - FORCING OUT A CONFESSION - Threshold Discernible Ring Signatures
SN - 978-989-8425-18-8
AU - Kumar S.
AU - Agrawal S.
AU - Venkatesan R.
AU - Lokam S.
AU - Pandu Rangan C.
PY - 2010
SP - 379
EP - 388
DO - 10.5220/0002984203790388