Chameleon: a Blind Double Trapdoor Hash Function for Securing AMI Data Aggregation

Data aggregation is an integral part of Advanced Metering Infrastructure (AMI) deployment that is implemented by the concentrator. Data aggregation reduces the number of transmissions, thereby reducing communication costs and increasing the bandwidth utilization of AMI. However, the concentrator poses a great risk of being tampered with, leading to erroneous bills and possible consumer disputes. In this paper, we propose an end-to-end integrity protocol using elliptic curve based chameleon hashing to provide data integrity and authenticity. The concentrator generates and sends a chameleon hash value of the aggregated readings to the Meter Data Management System (MDMS) for verification, while the smart meter with the trapdoor key computes and sends a commitment value to the MDMS so that the resulting chameleon hash value calculated by the MDMS is equivalent to the previous hash value sent by the concentrator. By comparing the two hash values, the MDMS can validate the integrity and authenticity of the data sent by the concentrator. Compared with the discrete logarithm implementation, the ECC implementation reduces the computational cost of MDMS, concentrator and smart meter by approximately 36.8%, 80%, and 99% respectively. We also demonstrate the security soundness of our protocol through informal security analysis

A Practical Searchable Symmetric Encryption Scheme for Smart Grid Data

Outsourcing data storage to the remote cloud can be an economical solution to enhance data management in the smart grid ecosystem. To protect the privacy of data, the utility company may choose to encrypt the data before uploading them to the cloud. However, while encryption provides confidentiality to data, it also sacrifices the data owners' ability to query a special segment in their data. Searchable symmetric encryption is a technology that enables users to store documents in ciphertext form while keeping the functionality to search keywords in the documents. However, most state-of-the-art SSE algorithms are only focusing on general document storage, which may become unsuitable for smart grid applications. In this paper, we propose a simple, practical SSE scheme that aims to protect the privacy of data generated in the smart grid. Our scheme achieves high space complexity with small information disclosure that was acceptable for practical smart grid application. We also implement a prototype over the statistical data of advanced meter infrastructure to show the effectiveness of our approach

Gelişmiş Ölçüm Altyapısı İçin Güvenlik Uygulamaları

Elektrik tüketimi ölçüm araçları, manuel olarak ölçüm yapılan analog sayaçlardan, elektrik tüketimi ile ilgili bilgileri toplayan ve elektrik dağıtım firmalarına ileten yeni akıllı sayaçlara doğru evrilmektedir. Sayaç verisinin okunmasını sağlayan tek yönlü otomatik sayaç okuma sistemlerinin (AMR) çıkışıyla sayaçlar akıllı şebeke yatırımlarının önemli bir kısmını oluşturmuştur. Otomatik sayaç okuma sistemleri ilk uygulamalar için cazip olmasına rağmen, çözülmesi gereken önemli bir husus olan talep tarafı yönetiminin AMR ile sağlanamadığı fark edilmiştir. AMR teknolojisinin kabiliyetlerinin tek yönlü sayaç verisi okuma ile sınırlı olması nedeniyle, sayaçlardan toplanan veriler üzerinden düzeltici önlemler alınmasına ve tüketicinin enerjiyi daha verimli akıllı kullanmasına yönelik özeliklere izin vermemektedir. Gelişmiş Ölçüm Altyapısı (AMI) ise akıllı sayaçlar ve dağıtım şirketleri arasında çift yönlü iletişim kurarak dağıtım şirketlerine sayaçlar üzerindeki parametreleri dinamik olarak değiştirme imkanı tanır. Bu nedenle, bu çalışmada AMI güvenliği üzerine odaklanılacaktır. Akıllı sayaç sistemlerinin yaygınlaşması ile birlikte, güvenlik bu sistemlerin gerekli ve kaçınılmaz bir ihtiyacı haline gelmektedir. Diğer taraftan, AMI sadece akıllı sayaçların fiziksel olarak dağıtımı manasına gelmemekte, ayrıca sayaç verilerinin yönetimi için gerekli olan karmaşık bir iletişim ağı ve bilgi teknolojileri altyapısını da içermektedir. Dolayısıyla güvenlik çözümlerini ele alırken geniş bir perspektifle yaklaşmak gerekmektedir. Bu nedenle de, sistemin kritik varlıkları belirlenmeli, tehditler iyi analiz edilmeli ve daha sonra güvenlik gereksinimleri iyi tanımlanmış olmalıdır. Bu çalışma AMI sisteminin temel güvenlik gereksinimleri, tehditlere karşı sistem kısıtlarını düşünerek olası çözümleri üzerine, şu anki güvenlik çözümlerini de resmederek, genel bir bakış sunmaktadır. Bu çalışmada, AMI sisteminin güvenlik gereksinimleri analiz edilecek, kısıtlar belirlenecek ve olası güvenlik tehditlerine karşı olası karşı önlemler belirlenecektir. Metering utilities have been replacing from analog meters that are read manually with new, smart meters that gather information about electricity consumption and transmit it back to electric companies. The metering has been the important part of the Smart Grid investments so far, with the initial introduction of one-way automated meter reading (AMR) systems to read meter data. Even though AMR technology proved to be initially enticing, utility companies have realized that AMR does not address demand-side management which is the major issue they need to solve. Since AMR’s capability is restricted to reading meter data due to its one-way communication system, it does not let utilities take corrective action based on the information gathered from the meters and does not assist customers in using energy intelligently. Advanced Metering Infrastructure (AMI) creates a two-way communication network between smart meters and utility systems and provides utilities the ability to modify service-level parameters dynamically. Therefore in this work we will also focus on AMI security practices. While smart metering systems are become widespread security is going to be the one of its essential and inevitable needs. On the other hand, AMI does not only mean the physical deployment of smart meters, but it also includes meter data management system which is a complicated communication network and IT infrastructure. Hence a broad perspective has to be adopted when security solutions are considered. Therefore, assets of the system must be identified, threats must be well analyzed and then security requirements must be well defined. This paper presents an overview on the main security requirements of the AMI, on the threats possible solutions considering the system constraints by picturing the current security solutions. In this work, the security requirements for AMI systems will be analyzed, constraints will be determined and possible countermeasures against security threats will be given

Security Challenges in Smart-Grid Metering and Control Systems

The smart grid is a next-generation power system that is increasingly attracting the attention of government, industry, and academia. It is an upgraded electricity network that depends on two-way digital communications between supplier and consumer that in turn give support to intelligent metering and monitoring systems. Considering that energy utilities play an increasingly important role in our daily life, smart-grid technology introduces new security challenges that must be addressed. Deploying a smart grid without adequate security might result in serious consequences such as grid instability, utility fraud, and loss of user information and energy-consumption data. Due to the heterogeneous communication architecture of smart grids, it is quite a challenge to design sophisticated and robust security mechanisms that can be easily deployed to protect communications among different layers of the smart grid-infrastructure. In this article, we focus on the communication-security aspect of a smart-grid metering and control system from the perspective of cryptographic techniques, and we discuss different mechanisms to enhance cybersecurity of the emerging smart grid. We aim to provide a comprehensive vulnerability analysis as well as novel insights on the cybersecurity of a smart grid