and analysis of the generic composition paradigm

Implementing copy protection on software is a difficult problem that has resisted a satisfactory solution for many years. This paper proposes a set of features that allows a machine to execute XOM code: code where neither the instructions or the data are visible to entities outside the running process. To support XOM code we use a machine that supports internal compartments, where a process in one compartment cannot read data from another compartment. All data that leaves the machine is encrypted, since we assume secure compartments cannot be guaranteed by anything outside the machine. The design of this machine poses some interesting trade-offs between security, efficiency and flexibility. We explore some of the potential security issues as one pushes the machine to become more efficient and flexible. Our analysis indicates, while not cheap, it is possible to create a normal multi-tasking machine where nearly all applications can be run in XOM mode. While a virtual XOM machine is possible, the underlying hardware needs to support a unique private key, asymmetric decryption, private memory, fast symmetric ciphers, and traps on cache misses for efficient operation.

Signcryption is a public key or asymmetric cryptographic method that provides simultaneously both message confidentiality and unforgeability at a lower computational and communication overhead.

Connectivity in today’s enterprise networks is regulated by a combination of complex routing and bridging policies, along with various interdiction mechanisms such as ACLs, packet filters, and other middleboxes that attempt to retrofit access control onto an otherwise permissive network architecture. This leads to enterprise networks that are inflexible, fragile, and difficult to manage. To address these limitations, we offer SANE, a protection architecture for enterprise networks. SANE defines a single protection layer that governs all connectivity within the enterprise. All routing and access control decisions are made by a logically-centralized server that grants access to services by handing out capabilities (encrypted source routes) according to declarative access control policies (e.g., “Alice can access

Storage outsourcing is a rising trend which prompts a number of interesting security issues, many of which have been extensively investigated in the past. However, Provable Data Possession (PDP) is a topic that has only recently appeared in the research literature. The main issue is how to frequently, efficiently and securely verify that a storage server is faithfully storing its client’s (potentially very large) outsourced data. The storage server is assumed to be untrusted in terms of both security and reliability. (In other words, it might maliciously or accidentally erase hosted data; it might also relegate it to slow or off-line storage.) The problem is exacerbated by the client being a small computing device with limited resources. Prior work has addressed this problem using either public key cryptography or requiring the client to outsource its data in encrypted form. In this paper, we construct a highly efficient and provably secure PDP technique based entirely on symmetric key cryptography, while not requiring any bulk encryption. Also, in contrast with its predecessors, our PDP technique allows outsourcing of dynamic data, i.e, it efficiently supports operations, such as block modification, deletion and append. 1.

We describe highly efficient constructions, XE and XEX, that turn a blockcipher E: K × {0, 1}^n → {0, 1}^n into a tweakable blockcipher...

The recently introduced Galois/Counter Mode (GCM) of operation for block ciphers provides both encryption and message authentication, using universal hashing based on multiplication in a binary finite field. We analyze its security and performance, and show that it is the most e#cient mode of operation for high speed packet networks, by using a realistic model of a network crypto module and empirical data from studies of Internet tra#c in conjunction with software experiments and hardware designs. GCM has several useful features: it can accept IVs of arbitrary length, can act as a stand-alone message authentication code (MAC), and can be used as an incremental MAC. We show that GCM is secure in the standard model of concrete security, even when these features are used. We also consider several of its important system-security aspects.

Abstract We put forward a new paradigm for building hybrid encryption schemes from constrainedchosen-ciphertext secure (CCCA) key-encapsulation mechanisms (KEMs) plus authenticated

Keywords: Associated-data problem, authenticated-encryption, block-cipher usage, key separation, modes of operation, OCB.

Abstract. We introduce CWC, a new block cipher mode of operation for protecting both the privacy and the authenticity of encapsulated data. CWC is currently the only such mode having all five of the following properties: provable security, parallelizability, high performance in hardware, high performance in software, and no intellectual property concerns. We believe that having all five of these properties makes CWC a powerful tool for use in many performance-critical cryptographic applications. CWC is also the only appropriate solution for some applications; e.g., standardization bodies like the IETF and NIST prefer patent-free modes, and CWC is the only such mode capable of processing data at 10Gbps in hardware, which will be important for future IPsec (and other) network devices. As part of our design, we also introduce a new parallelizable universal hash function optimized for performance in both hardware and software.