7095140
Secure Multicast Using Proxy Encryption
In a secure multicast communication environment, only valid members belong to the multicast group could decrypt the data. In many previous researches, there is one “group key” shared by all group members. However, this incurs the so-called “1 affects n problem,” that is, an action of one member affects the whole group. We believe this is the source of scalability problems. Moreover, from the administrative perspective, it is desired to confine the impacts of changing membership events in a local area. In this paper, we propose a new secure multicast architecture without using a group key. We exploit a cryptographic primitive “proxy encryption.” It allows routers to convert a ciphertext encrypted under a key to a ciphertext encrypted under another key, without revealing the secret key and the plaintext. By giving proper keys to intermediate routers, routers could provide separation between subgroups. Therefore the goals of scalability and containment are achieved.
14142232
Confessible Threshold Ring Signatures
We present two threshold ring signature schemes with different properties. One focuses on the confessibility (or signer verifiability) and the denouncibility properties. The other focuses on the threshold-confessibility. Our schemes are built on generic ring signature schemes and can be easily adapted to most existing ring signature schemes. Based on the former works, we also construct a realization of our schemes as an example. We prove that our schemes are secure in the random oracle model.
9639915
Support for adaptivity in ARMCI using migratable objects
Many new paradigms of parallel programming have emerged that compete with and complement the standard and well-established MPI model. Most notable, and successful, among these are models that support some form of global address space. At the same time, approaches based on migratable objects (also called virtualized processes) have shown that resource management concerns can be separated effectively from the overall parallel programming effort. For example, Charm++ supports dynamic load balancing via an intelligent adaptive run-time system. It is also becoming clear that a multi-paradigm approach that allows modules written in one or more paradigms to coexist and co-operate will be necessary to tame the parallel programming challenge. ARMCI is a remote memory copy library that serves as a foundation of many global address space languages and libraries. This paper presents our preliminary work on integrating and supporting ARMCI with the adaptive run-time system of Charm++ as a part of our overall effort in the multi-paradigm approach
17852820
Fault pattern oriented defect diagnosis for memories
Failure analysis (FA) and diagnosis of memory cores plays a key role in system-on-chip (SOC) product development and yield ramp-up. Conventional FA based on bitmaps and the experiences of the FA engineer is time consuming and error prone. The increasing time-to-volume pressure on semiconductor products calls for new development flow that enables the product to reach a profitable yield level as soon as possible. Demand in methodologies that allow FA automation thus increases rapidly in recent years. This paper proposes a systematic diagnosis approach based on failure patterns and functional fault models of semiconductor memories. By circuit-level simulation and analysis, we have also developed a fault pattern generator. Defect diagnosis and FA can be performed automatically by using the fault patterns, reducing the time in yield improvement. The main contribution of the paper is thus a methodology and procedure for accelerating FA and yield optimization for semiconductor memories.
6577464
An HMAC processor with integrated SHA-1 and MD5 algorithms
Cryptographic algorithms are prevalent and important in digital communications and storage, e.g., both SHA-1 and MD5 algorithms are widely used hash functions in IPSec and SSL for checking the data integrity. In this paper, we propose a hardware architecture for the standard HMAC function that supports both. Our HMAC design automatically generates the padding words and reuses the key for consecutive HMAC jobs that use the same key. We have also implemented the HMAC design in silicon. Compared with existing designs, our HMAC processor has lower hardware cost---12.5% by sharing of the SHA-1 and MD5 circuitry and a little performance penalty.
8545280
EnviroStore: A Cooperative Storage System for Disconnected Operation in Sensor Networks
This paper presents a new cooperative storage system for sensor networks geared for disconnected operation (where sensor nodes do not have a connected path to a basestation). The goal of the system is to maximize its data storage capacity by appropriately distributing storage utilization and opportunistically offloading data to external devices when possible. The system is motivated by the observation that a large category of sensor network applications, such as environmental data logging, does not require real-time data access. Such networks generally operate in a disconnected mode. Rather than focusing on multihop routing to a basestation, an important concern becomes (i) to maximize the effective storage capacity of the disconnected sensor network such that it accommodates the most data, and (ii) to take the best advantage of data upload opportunities when they become available to relieve network storage. The storage system described in this paper achieves the above goals, leading to significant improvements in the amount of data collected compared to non-cooperative storage. It is implemented in nesC for TinyOS and evaluated in TOSSIM through various application scenarios.
3172548
Key trees and the security of interval multicast
A key tree is a distributed data structure of security keys that can be used by a group of users. In this paper we describe how any user in the group can use the different keys in the key tree to securely multicast data to different subgroups within the group. The cost of securely multicasting data to a subgroup whose users are "consecutive" is O(log n) encryptions, where n is the total number of users in the group. The cost of securely multicasting data to an arbitrary subgroup is O(n/2) encryptions. However this cost can be reduced to one encryption by introducing an additional key tree to the group.