Space-Time Storage Codes for Wireless Distributed Storage Systems

TL;DR

This paper introduces space-time storage codes to enhance physical layer robustness in wireless distributed storage systems, addressing the need for cross-layer protection against fading channels, especially in large helper networks.

Contribution

It pioneers the concept of space-time storage codes, integrating network and physical layer functionalities for wireless DSSs, and highlights the need for less complex transmission protocols.

Findings

Proposes the first space-time storage code framework for wireless DSSs

Identifies complexity issues with existing space-time codes in large helper networks

Suggests the development of simpler transmission protocols for practical deployment

Abstract

Distributed storage systems (DSSs) have gained a lot of interest recently, thanks to their robustness and scalability compared to single-device storage. Majority of the related research has exclusively concerned the network layer. At the same time, the number of users of, e.g., peer-to-peer (p2p) and device-to-device (d2d) networks as well as proximity based services is growing rapidly, and the mobility of users is considered more and more important. This motivates, in contrast to the existing literature, the study of the physical layer functionality of wireless distributed storage systems. In this paper, we take the first step towards protecting the storage repair transmissions from physical layer errors when the transmission takes place over a fading channel. To this end, we introduce the notion of a space-time storage code, drawing together the aspects of network layer and physical layer functionality and resulting in cross-layer robustness. It is also pointed out that existing space-time codes are too complex to be utilized in storage networks when the number of helpers involved is larger than the number of receive antennas at the newcomer or data collector, hence creating a call for less complex transmission protocols.