hierarchical reduction scheme whereby entire control con-structs are reduced to an object similar to an operation in a basic block. With this scheme, all innermost loops, including those containing conditional statements, can be software pipelined. It also diminishes the start-up cost of loops with small

We describe a new scalable application-layer multicast protocol, specifically designed for low-bandwidth, data streaming applications with large receiver sets. Our scheme is based upon a hierarchical clustering of the application-layer multicast peers and can support a number of different data

This paper proposes a medium access control (MAC) protocol for ad hoc wireless networks that utilizes multiple channels dynamically to improve performance. The IEEE 802.11 standard allows for the use of multiple channels available at the physical layer, but its MAC protocol is designed only for a

for hierarchical access control, which considers both partially ordered user relations and partially ordered data stream relations. We also propose an algorithm for constructing a logical key graph, which is suitable even when users and data streams have complex relations. Simulation results show that our scheme

A scheme based on cryptography is proposed for access control in a system where hierarchy is represented by a partially ordered set (or poset). Straightforward implementation f the scheme requires users highly placed in the hierarchy to store a large number of cryptographic keys. A time

popular as a method for managing encrypted file systems. Although efficiently computable, the wide-spread adoption of BBS re-encryption has been hindered by considerable security risks. Following recent work of Ivan and Dodis, we present new re-encryption schemes that realize a stronger notion of security

All organizations share data in a carefully managed fashion by using access control mechanisms. We focus on enforcing access control by encrypting the data and managing the encryption keys. We make the realistic assumption that the structure of any organization is a hierarchy of security classes

time and applying an adaptive playback point scheme to help achieve more successful retransmission, and (2) adapting to network congestion and heterogeneity using hierarchical rate control mechanism. This paper concentrates on the rate control aspects of LVMR. In contrast to the existing sender

on the maximum length of public parameter will be a weakness for stability, in dynamic key management. Number and length of changed public parameter are considered for the interaction between CA and trusted public platform in dynamic management. The paper proposes an improved scheme to optimize storage space

A key assignment scheme is a cryptographic technique for implementing an information flow policy, sometimes known as hierarchical access control. All the research to date on key assignment schemes has focused on particular encryption techniques rather than an analysis of what features are required