Masana Murase

Effective implementation of the cell broadband engine™ isolation loader

This paper presents the design and implementation of the Cell Broadband Engine TM(Cell/B.E.) isolation loader which is a part of the IBM Software Development Kit for Multicore Acceleration [14]. Our isolation loader is a key component in realizing secure application boot and encrypted application execution. During the application load process, the isolation loader fetches, validates, and decrypts a Synergistic Processor Element (SPE) executable, establishing a chain of trust from the hardware to the application. Since not all applications are SPE executables, we also introduce a general solution. This is a verification service framework in which all applications including system functions can be verified by the isolation loader immediately before execution. We have applied several novel implementation techniques to the isolation loader. The countermeasure implemented in our isolation loader against the substituted-ciphertext attack is given and our staging technique to allocate contiguous working areas for applications is also introduced. The load overhead of this loader including application fetch, validation (RSA-2048/SHA-1), and decryption (RSA-2048 and AES) is less than 50 milliseconds on the 2.8 GHz IBM PowerXCell 8i processor. This overhead is reasonable compared with the 500-millisecond 2048-bit RSA signing needed by the Trusted Platform Module chips [3].

Automatic Resource Scheduling with Latency Hiding for Parallel Stencil Applications on GPGPU Clusters

Overlapping computations and communication is a key to accelerating stencil applications on parallel computers, especially for GPU clusters. However, such programming is a time-consuming part of the stencil application development. To address this problem, we developed an automatic code generation tool to produce a parallel stencil application with latency hiding automatically from its dataflow model. With this tool, users visually construct the workflows of stencil applications in a dataflow programming model. Our dataflow compiler determines a data decomposition policy for each application, and generates source code that overlaps the stencil computations and communication (MPI and PCIe). We demonstrate two types of overlapping models, a CPU-GPU hybrid execution model and a GPU-only model. We use a CFD benchmark computing 19-point 3D stencils to evaluate our scheduling performance, which results in 1.45 TFLOPS in single precision on a cluster with 64 Tesla C1060 GPUs.

A parallel programming framework orchestrating multiple languages and architectures

This paper presents a novel parallel programming framework that orchestrates multiple languages such as C, C++, and Fortran and multiple computational architectures such as x86, POWER, and NVIDIAs Fermi to enhance productivity of parallel stencil applications while supporting high performance. Unlike traditional parallel programming frameworks, our framework provides three unique features: (1) simple meta-level, visual programming to construct workflows of components written in traditional programming languages, (2) optimal component parallelization and resource scheduling with the stencil communication pattern resolution, and (3) automatic network code generation including MPI, sockets, memory copies, and pointer passing. We prototyped incompressible computational fluid dynamics applications and demonstrate the effectiveness of our approach by evaluating our framework.

Anonymity-Aware Face-to-Face Mobile Payment

On-line payments are increasingly popular in paying bills for Internet shopping, and payment-capable mobile phones support making purchases anytime and anywhere, without cash. However, mobile payments are rarely used for making face-to-face payments, with concerns about anonymity, security, and usability. This paper proposes a face-to-face mobile payment protocol that addresses these concerns. To address anonymity and security concerns, the proposed protocol uses unique information for the payment transaction, such as the location and the time, and introduces two procedures for optimizing the matching time slots and exchanging random numbers when needed, to secure the transactions without exposing the seller’s or the buyer’s personal identification. To address usability concerns, the proposed protocol optimizes the parameters for the two introduced procedures to match the seller-buyer pairs, depending on the number of the people involved in the mobile payments, the delays caused by human operations with the mobile phones, mobile communication, and so on. Experimental results prove that the proposed protocol is practical, solving the addressed concerns.