1,859 research outputs found
Provable Efficient Certificateless Public Key Encryption
Certificateless public key cryptography was introduced to overcome
the key escrow limitation of the identity-based cryptography. It
combines the advantages of the identity-based cryptography and the
traditional PKI. Recently, Dae Hyun Yum1 and Pil Joong Lee have
proposed a generic series construction model of certificateless
public key encryption (CL-PKE) which is built from generic
primitives: identity-based encryption and public key encryption.
However, this model pays much attention on the generic construction
and neglects the nice properties of the bilinear pairings. In this
paper, we propose an efficient CL-PKE scheme which is based on the
nice algebraic properties of Weil pairing. The scheme works in a
kind of parallel model and it is more efficient on computation or
published public key information than the existing schemes
Still Wrong Use of Pairings in Cryptography
Several pairing-based cryptographic protocols are recently proposed with a
wide variety of new novel applications including the ones in emerging
technologies like cloud computing, internet of things (IoT), e-health systems
and wearable technologies. There have been however a wide range of incorrect
use of these primitives. The paper of Galbraith, Paterson, and Smart (2006)
pointed out most of the issues related to the incorrect use of pairing-based
cryptography. However, we noticed that some recently proposed applications
still do not use these primitives correctly. This leads to unrealizable,
insecure or too inefficient designs of pairing-based protocols. We observed
that one reason is not being aware of the recent advancements on solving the
discrete logarithm problems in some groups. The main purpose of this article is
to give an understandable, informative, and the most up-to-date criteria for
the correct use of pairing-based cryptography. We thereby deliberately avoid
most of the technical details and rather give special emphasis on the
importance of the correct use of bilinear maps by realizing secure
cryptographic protocols. We list a collection of some recent papers having
wrong security assumptions or realizability/efficiency issues. Finally, we give
a compact and an up-to-date recipe of the correct use of pairings.Comment: 25 page
On the Relations Between Diffie-Hellman and ID-Based Key Agreement from Pairings
This paper studies the relationships between the traditional Diffie-Hellman
key agreement protocol and the identity-based (ID-based) key agreement protocol
from pairings.
For the Sakai-Ohgishi-Kasahara (SOK) ID-based key construction, we show that
identical to the Diffie-Hellman protocol, the SOK key agreement protocol also
has three variants, namely \emph{ephemeral}, \emph{semi-static} and
\emph{static} versions. Upon this, we build solid relations between
authenticated Diffie-Hellman (Auth-DH) protocols and ID-based authenticated key
agreement (IB-AK) protocols, whereby we present two \emph{substitution rules}
for this two types of protocols. The rules enable a conversion between the two
types of protocols. In particular, we obtain the \emph{real} ID-based version
of the well-known MQV (and HMQV) protocol.
Similarly, for the Sakai-Kasahara (SK) key construction, we show that the key
transport protocol underlining the SK ID-based encryption scheme (which we call
the "SK protocol") has its non-ID counterpart, namely the Hughes protocol.
Based on this observation, we establish relations between corresponding
ID-based and non-ID-based protocols. In particular, we propose a highly
enhanced version of the McCullagh-Barreto protocol
An identity-based key infrastructure suitable for messaging applications
Abstract—Identity-based encryption (IBE) systems are relatively recently proposed; yet they are highly popular for messaging applications since they offer new features such as certificateless infrastructure and anonymous communication. In this paper, we intended to propose an IBE infrastructure for
messaging applications. The proposed infrastructure requires one registration authority and at least one public key generator and they secret share the master secret key. In addition, the PKG also shares the same master secret with each user in the system in a different way. Therefore, the PKG will never be able to learn the private keys of users under non-collusion assumption. We discuss different aspects of the proposed infrastructure such as security, key revocation, uniqueness of the identities that constitute the main drawbacks of other IBE schemes. We demonstrate that our infrastructure solves many of these drawbacks under certain assumptions
Efficient algorithms for pairing-based cryptosystems
We describe fast new algorithms to implement recent cryptosystems based on the Tate pairing. In particular, our techniques improve pairing evaluation speed by a factor of about 55 compared to previously known methods in characteristic 3, and attain performance comparable
to that of RSA in larger characteristics.We also propose faster algorithms for scalar multiplication in characteristic 3 and square root extraction
over Fpm, the latter technique being also useful in contexts other than that of pairing-based cryptography
ID-based Ring Signature and Proxy Ring Signature Schemes from Bilinear Pairings
In 2001, Rivest et al. firstly introduced the concept of ring signatures. A
ring signature is a simplified group signature without any manager. It protects
the anonymity of a signer. The first scheme proposed by Rivest et al. was based
on RSA cryptosystem and certificate based public key setting. The first ring
signature scheme based on DLP was proposed by Abe, Ohkubo, and Suzuki. Their
scheme is also based on the general certificate-based public key setting too.
In 2002, Zhang and Kim proposed a new ID-based ring signature scheme using
pairings. Later Lin and Wu proposed a more efficient ID-based ring signature
scheme. Both these schemes have some inconsistency in computational aspect.
In this paper we propose a new ID-based ring signature scheme and a proxy
ring signature scheme. Both the schemes are more efficient than existing one.
These schemes also take care of the inconsistencies in above two schemes.Comment: Published with ePrint Archiv
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