Ngoc Hong Tran¹, Cao Vien Phung², Binh Quoc Nguyen¹, Leila Bahri³ and Dung Hai Dinh¹, ¹Vietnamese German University, Vietnam, ²Technische Universitat Carolo-Wilhelmina zu Braunschweig, Germany and³KTH, Sweden

In this paper, we investigate a simple but effective coding mechanism, namely Coding Opportunistically (COPE) [1], and the privacy violations which are likely to happen to COPE. The COPE data, from the source node through the network to its destination node, can be easily learned by the surrounding nodes, particularly, intersecting nodes and neighbour nodes. This leads to a serious consequence in leaking the node identity and its private data. In order to cope with the mentioned issues, we can apply cryptographic schemes. However, the security solutions often exploit the public key schemes which nowadays run more slowly and give the longer encrypted values as the effects of the key size increase to guarantee the algorithm complexity. Hence, while the coding mechanism aims to decrease the bandwidth consumption by aggregating (i.e., coding) multiple packets in the network, the security solutions increase the data quantity. However, a necessary needs of combining data coding mechanism and cryptographic algorithm is raised for both preserving privacy and optimizing bandwidth use at the same time as mentioned above. In this paper we thus propose SCOPE, a lightweight privacy preserving approach able to support nodes running the COPE protocol in a secret way, by adopting the Elliptic Curve Cryptography (ECC) homomorphic encryption algorithm. The proposal’s effectiveness and efficiency are proved through a variety of experiments.

Network Coding, Peer-to-Peer, Homomorphic Encryption, Elliptic Curve Cryptography (ECC).