elliptic curve cryptography

The Internet of Things has significantly improved healthcare with its promise of transforming technological, social, and economic perspectives. Medical devices with wireless internet access enable remote monitoring of patients, and collectively, these increasingly smart and connected medical devices can provide unique and contemporary medical and health services envisioned to be deployed in a large-scale fashion. For this, medical data and records generally are collected, stored, and shared through open-air wireless networks and public cloud infrastructures, which poses severe challenges regarding the confidentiality of sensitive medical data while maintaining low service overhead and system complexity. This paper presents a novel scheme for secure cloud-assisted Internet of Medical Things connecting patients/smart medical devices to smart applications/medical service providers in a scalable one-to-many fashion to make novel medical services practical. The proposed scheme uses index-based searchable encryption for data screening without decryption. It uses a low-overhead proxy re-encryption scheme for secure data sharing through public clouds

Smart grids using information technology (IT) and communication networks control smart home appliances to reduce costs and increase reliability and transparency. Preserving the privacy of the user data is one of the biggest challenges in smart grid research; by disclosing user-related data, an internal or external adversary can understand the habits and behavior of the users. A solution to address this challenge is, however, a data aggregation mechanism in which the aggregated data of all of the users in a residential area. The security and efficiency of the data aggregation approach are important. The drawback of the previous works is leaking fine-grained user data or the high computation and communication overhead. In this paper, we present an efficient privacy-preserving data-aggregation protocol, called PPDA, based on the Elliptic Curve Cryptography (ECC) and Anonymous Veto network protocol. The PPDA protocol aggregates metering data efficiently and securely so that it becomes applicable for resource-constraint metering devices. We also present an improved multi-cycle proposal of PPDA, called MC-PPDA. In the improved approach, the system initialization step runs only at the first cycle of the protocol which increases the efficiency of the protocol. Evaluation results show that the proposed approaches preserve the privacy of the fine-grained user data against an internal and external adversary; the improved multi-cycle approach is also secure against collusion. Compared to the previous approaches, the proposed approaches incur less computation and communication overhead.

This paper presents two efficient implementations of fast and pipelined bit-parallel polynomial basis multipliers over GF (2m) by irreducible pentanomials and trinomials. The architecture of the first multiplier is based on a parallel and independent computation of powers of the polynomial variable. In the second structure only even powers of the polynomial variable are used. The parallel computation provides regular and low-cost structure with low critical path delay. In addition، the pipelining technique is applied to the proposed structures to shorten the critical path and to perform the computation in two clock cycles. The implementations of the proposed methods over the binary extension fields GF (2163) and GF (2233) have been successfully verified and synthesized using Xilinx ISE 11 by Virtex-4، XC4VLX200 FPGA.

A new and highly efficient architecture for elliptic curve scalar point multiplication is presented. To achieve the maximum architectural and timing improvements we have reorganized and reordered the critical path of the Lopez-Dahab scalar point multiplication architecture such that logic structures are implemented in parallel and operations in the critical path are diverted to noncritical paths. The results we obtained show that with G = 55 our proposed design is able to compute GF(2163) elliptic curve scalar multiplication in 9.6 μs with the maximum achievable frequency of 250 MHz on Xilinx Virtex-4 (XC4VLX200), where G is the digit size of the underlying digit-serial finite field multiplier. Another implementation variant for less resource consumption is also proposed. With G=33, the design performs the same operation in 11.6 μs at 263 MHz on the same platform. The results of synthesis show that in the first implementation 17929 slices or 20% of the chip area is occupied which makes it suitable for speed critical cryptographic applications while in the second implementation 14203 slices or 16% of the chip area is utilized which makes it suitable for applications that may require speed-area trade-off. The new design shows superior performance compared to the previously reported designs.