Improved perfect secrecy of distributed storage systems using interference alignment

Abstract

Regenerating codes based on the approach of interference alignment for wireless interference channel achieve the cut-set bound for distributed storage systems (DSS). These codes are especially important for efficient repair of a failed node in a minimum storage regenerating (MSR) codes. Moreover, they achieve perfect security against the eavesdropper attacks, i.e., the observer can not reveal the whole message. Here the aim is information protection of individual files and small groups from the entire message, when the attacker has access to a limited number of storage nodes. This paper considers improving the perfect security in such DSS. The enhanced secrecy is presented by performing explicit code construction by using an outer and an inner code. The proposed construction code model includes coset code as an outer code or pre-coding step that ensures the security of the system and an MSR interference alignment code as an inner one that performs an efficient reconstruction and repair process. Using this construction we show that the eavesdropper can not reveal the message, and, that he can not access any subset of individual information from the original message, without any significant loss in the storage capacity.