9,961 research outputs found
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
THRIVE: Threshold Homomorphic encryption based secure and privacy preserving bIometric VErification system
In this paper, we propose a new biometric verification and template
protection system which we call the THRIVE system. The system includes novel
enrollment and authentication protocols based on threshold homomorphic
cryptosystem where the private key is shared between a user and the verifier.
In the THRIVE system, only encrypted binary biometric templates are stored in
the database and verification is performed via homomorphically randomized
templates, thus, original templates are never revealed during the
authentication stage. The THRIVE system is designed for the malicious model
where the cheating party may arbitrarily deviate from the protocol
specification. Since threshold homomorphic encryption scheme is used, a
malicious database owner cannot perform decryption on encrypted templates of
the users in the database. Therefore, security of the THRIVE system is enhanced
using a two-factor authentication scheme involving the user's private key and
the biometric data. We prove security and privacy preservation capability of
the proposed system in the simulation-based model with no assumption. The
proposed system is suitable for applications where the user does not want to
reveal her biometrics to the verifier in plain form but she needs to proof her
physical presence by using biometrics. The system can be used with any
biometric modality and biometric feature extraction scheme whose output
templates can be binarized. The overall connection time for the proposed THRIVE
system is estimated to be 336 ms on average for 256-bit biohash vectors on a
desktop PC running with quad-core 3.2 GHz CPUs at 10 Mbit/s up/down link
connection speed. Consequently, the proposed system can be efficiently used in
real life applications
An Authentication Protocol for Future Sensor Networks
Authentication is one of the essential security services in Wireless Sensor
Networks (WSNs) for ensuring secure data sessions. Sensor node authentication
ensures the confidentiality and validity of data collected by the sensor node,
whereas user authentication guarantees that only legitimate users can access
the sensor data. In a mobile WSN, sensor and user nodes move across the network
and exchange data with multiple nodes, thus experiencing the authentication
process multiple times. The integration of WSNs with Internet of Things (IoT)
brings forth a new kind of WSN architecture along with stricter security
requirements; for instance, a sensor node or a user node may need to establish
multiple concurrent secure data sessions. With concurrent data sessions, the
frequency of the re-authentication process increases in proportion to the
number of concurrent connections, which makes the security issue even more
challenging. The currently available authentication protocols were designed for
the autonomous WSN and do not account for the above requirements. In this
paper, we present a novel, lightweight and efficient key exchange and
authentication protocol suite called the Secure Mobile Sensor Network (SMSN)
Authentication Protocol. In the SMSN a mobile node goes through an initial
authentication procedure and receives a re-authentication ticket from the base
station. Later a mobile node can use this re-authentication ticket when
establishing multiple data exchange sessions and/or when moving across the
network. This scheme reduces the communication and computational complexity of
the authentication process. We proved the strength of our protocol with
rigorous security analysis and simulated the SMSN and previously proposed
schemes in an automated protocol verifier tool. Finally, we compared the
computational complexity and communication cost against well-known
authentication protocols.Comment: This article is accepted for the publication in "Sensors" journal. 29
pages, 15 figure
Enhancing an Embedded Processor Core with a Cryptographic Unit for Performance and Security
We present a set of low-cost architectural enhancements to accelerate the execution of certain arithmetic operations common in cryptographic applications on an extensible embedded processor core. The proposed enhancements are generic in the sense that they can be beneficially applied in almost any RISC processor. We implemented the enhancements in form of a cryptographic unit (CU) that offers the programmer an extended instruction set. The CU features a 128-bit wide register file and datapath, which enables it to process 128-bit words and perform 128-bit loads/stores. We analyze the speed-up factors for some arithmetic operations and public-key cryptographic algorithms obtained through
these enhancements. In addition, we evaluate the hardware overhead (i.e. silicon area) of integrating the CU into an embedded RISC processor. Our experimental results show that the proposed architectural enhancements allow for a
significant performance gain for both RSA and ECC at the expense of an acceptable increase in silicon area. We also demonstrate that the proposed enhancements facilitate the protection of cryptographic algorithms against certain types of side-channel attacks and present an AES implementation
hardened against cache-based attacks as a case study
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