Information Security in Data and Storage Grids through GS3

Introduction

The actual Information Technology (IT) trend definitely brings towards network-distributed paradigms of computing. Among them, the grid is one of the most widely spread. Its success is due to the fact that it manages and makes available large quantities/amounts of computing and storage resources for allocating and elaborating data as required by users’ computation workflows. The management of such resources is transparent to the user that only has to specify his /her requirements in terms of resources. Then, the grid system manager automatically determines where the process is executed and which resources have to be allocated to it (Foster, & Kesselman, 1998). Sharing data in distributed multi-user environments triggers problems of security concerning data confidentiality and integrity. Grid middlewares usually provide resources management’s capabilities, ensuring security on accessing services and on communicating data, but they often lacks of data protection from direct malicious accesses, at system level. In other words, the fact that data are disseminated and stored in remote distributed machines, directly accessible from their administrators, constitutes the main risk for data security in grid environment. Security problems, such as insider abuse/attack, identity thefts and/or account hijacking, are often not adequately covered in grid context. It is therefore mandatory to introduce an adequate data protection mechanism, which denies data intelligibility to unauthorized users, also if they are (local) system administrators.

The problem of a secure storage access has been mainly faced in literature as definition of access rights (Junrang et al., 2004), in particular addressing problems of data sharing, whilst the coding of the data is demanded to the user, since no automatic mechanism to access to a secure storage space in a transparent way has been defined.

Scardaci, & Scuderi, (2007) proposed a technique for securing data disseminated over grid gLite (gLite, 2010) environment based on symmetric cryptography (Advanced Encryption Standard, AES). The key security is entrusted to a unique keystore server that stores it, to which all the data access requests must be notified in order to decrypt the data. This algorithm implements a spatial security policy: the security lies in physically hiding and securing the keystore server, and the access to the keystore is physically restricted and monitored in order to protect from malicious users, external attacks and insider abuses. Seitz, Pierson, & Brunie (2003) studied in depth the problem of data access, and propose a solution based on symmetric keys. In order to prevent non-authorized accesses to the symmetric key the authors propose to subdivide it on different servers. A similar technique has been specified by Shamir (1979), used in PERROQUET (Blanchet, Mollon, & Deleage, 2006) to modify the PARROT middleware (Thain, & Livny, 2005) by adding an encrypted file manager. The main contribution of such work is that, by applying the proposed algorithm, the (AES) symmetric key, split in N parts, can be recomposed if and only if all the N parts are available. HYDRA (2010) implements a data sharing service in gLite 3.0 medical environments, securing data by using the symmetric cryptography and splitting the keys among three keystore servers (Montagnat et al., 2006).