In the smart grid, huge amounts of consumption data are used to train deep learning models for applications such as load monitoring and demand response. However, these applications raise concerns regarding security and have high accuracy requirements. In one hand, the data used is privacy-sensitive. For instance, the fine-grained data collected by a smart meter at a consumer's home may reveal information on the appliances and thus the consumer's behaviour at home. On the other hand, the deep learning models require big data volumes with enough variety and to be trained adequately. In this paper, we evaluate the use of Edge computing and federated learning, a decentralized machine learning scheme that allows to increase the volume and diversity of data used to train the deep learning models without compromising privacy. This paper reports, to the best of our knowledge, the first use of federated learning for household load forecasting and achieves promising results. The simulations were done using Tensorflow Federated on the data from 200 houses from Texas, USA.

Electrical Load Forecasting Using Edge Computing and Federated Learning

A comprehensive survey of modern symmetric cryptographic solutions for resource constrained environments

Open multi-agent systems (MASs) have growing popularity in the Multi-agent Systems community and are predicted to have many applications in future, as large scale distributed systems become more widespread. A major practical limitation to open MASs is security because the openness of such systems negates many traditional security solutions. In this paper we introduce and classify main attacks on open MASs. We then survey and analyse various security techniques in the literature and categorise them under prevention and detection approaches. Finally, we suggest which security technique is an appropriate countermeasure for which classes of attack.

A review of attacks and security approaches in open multi-agent systems

Over the last few years, identity (ID)-based encryption (IBE) without requiring certificate management offers a practical alternative to public key encryption. However, how to revoke misbehaving/compromised identities in ID-based public key setting becomes a new and critical issue. In the past, there was little work on studying this revocation problem. In 2008, Boldyreva et al. proposed a revocable IBE (RIBE) and its associated revocation solution that used a binary tree structure to reduce the authority's periodic workload in Boneh and Franklin's IBE. However, Boldyreva et al.'s RIBE raised enormous computation costs for encryption and decryption procedures. Both IBEs require a secure channel between each user and the authority to transmit user's periodic private keys, thus the authority and each user need to encrypt and decrypt the private keys for each period. In this article, we present an efficient RIBE with a public channel, which provides a practical alternative to the previously proposed revocation solutions, while it remains efficient for encryption and decryption. Under the bilinear Diffie–Hellman assumption, we demonstrate that our RIBE with a public channel is semantically secure against adaptive chosen plaintext attacks and adaptive chosen ciphertext attacks.

Efficient Revocable ID-Based Encryption with a Public Channel

Differential fault analysis on block cipher SEED

Strong unforgeability in group signature schemes

We propose new double-block-length hash functions. Our approach for constructing collision-resistant double-block-length hash functions is to convert a blockcipher E with n -bit block length and 2n -bit key length to a 3-round Feistel cipher E * with 2n -bit block length, and then to embed E * in PGV compression functions. We prove that 12 hash functions with the group-1 PGV compression functions in which E * is embedded are collision-resistant in the ideal cipher model. Furthermore, since our hash functions have the hash rate 2/3, they are more efficient than any other existing double-block-length hash functions in terms of the number of blockcipher calls required for processing messages.

A New Double-Block-Length Hash Function Using Feistel Structure

The traceability is one of the core requirements for group signature schemes. Group signature schemes based on the bilinear mapping were proposed. The bilinearity of a bilinear mapping allows an efficient signature scheme verification for signature schemes based on the discrete logarithm type problem. But the bilinearity of a bilinear mapping can be an attack point with respect to the traceability for group signature schemes when it is designed in such a way that the linearity can be preserved. We show that Cheng-Zhu-Qiu-Wang's group signature schemes (X. Chen et al., 2005) based on bilinear mapping have no traceability property due to their improper use of a bilinear mapping in their signature generation and verification step. We also propose security enhanced group signature schemes for both of mini group signature scheme and improved group signature scheme of Cheng-Zhu-Qiu-Wang's

Untraceability of Group Signature Schemes based on Bilinear Mapping and Their Improvement

An offline E-cash system is presented that offers appreciably greater security and better privacy than currently considered E-cash system with similar functionality. Most off-line E-cash systems use the temper-resistant IC card which controls an E-cash issued by the card issuer. Offline E-cash system based on IC card has the threats of overspending, double spending, forgery E-cash, altering/eavesdropping transaction contents, etc. To prevent the above threats, there have been a lot of technical discussions of the security requirements for theoretical offline E-cash protocols based on IC card. However, there has been little attention paid to the security requirements for practical offline E-cash system based on IC card including entity authentication, key management, implementation of cryptographic algorithm, etc. Thus, this paper describes the security requirements for cryptographic algorithms, integrity for implementation of cryptographic algorithm, authentication module, key management, and E-cash protocols

The Security Requirement for off-line E-cash system based on IC Card

Chai, Cao and Lu first proposed an ID-based threshold decryption scheme without random oracles. Their approach is based on the Bilinear Diffie-Hellman Inversion assumption, and prove that it is selective chosen plaintext secure without random oracles. However, to ensure correctness of their ID-based threshold decryption scheme, it is necessary to guarantee that the shared decryption is performed correctly through some public verification function. We modify Chai et al.’s scheme to ensure that all decryption shares are consistent. We also present the first mediated ID based encryption scheme based on the Bilinear Diffie Hellman Inversion assumption without random oracles. In addition, we extend it into a mediated hierarchical ID-based encryption scheme.

Haeryong Park

Papers

Strong unforgeability in group signature schemes

A New Double-Block-Length Hash Function Using Feistel Structure

Untraceability of Group Signature Schemes based on Bilinear Mapping and Their Improvement

The Security Requirement for off-line E-cash system based on IC Card

Modified ID-Based threshold decryption and its application to mediated ID-Based encryption