Verifying hardware compilers

The use of hardware compilers to generate complex circuits from a high-level description is becoming more and more prevalent in a variety of application areas. However, this introduces further risks as the compilation process may introduce errors in otherwise correct high-level descriptions of circuits. In this paper, we present techniques to enable the automatic verification of hardware compilers through the use of finite-state model checkers. We illustrate the use of these techniques on a simple regular expression hardware compiler and discuss how these techniques can be further developed and used on more complex hardware- description languages.peer-reviewe

An embedded language framework for hardware compilation

Various languages have been proposed to describe synchronous hardware at an abstract, yet synthesisable level. We propose a uniform framework within which such languages can be developed, and combined together for simulation, synthesis, and verification. We do this by embedding the languages in Lava — a hardware description language (HDL), itself embedded in the functional programming language Haskell. The approach allows us to easily experiment with new formal languages and language features, and also provides easy access to formal verification tools aiding program verification.peer-reviewe

Parallel Architectures for Planetary Exploration Requirements (PAPER)

The Parallel Architectures for Planetary Exploration Requirements (PAPER) project is essentially research oriented towards technology insertion issues for NASA's unmanned planetary probes. It was initiated to complement and augment the long-term efforts for space exploration with particular reference to NASA/LaRC's (NASA Langley Research Center) research needs for planetary exploration missions of the mid and late 1990s. The requirements for space missions as given in the somewhat dated Advanced Information Processing Systems (AIPS) requirements document are contrasted with the new requirements from JPL/Caltech involving sensor data capture and scene analysis. It is shown that more stringent requirements have arisen as a result of technological advancements. Two possible architectures, the AIPS Proof of Concept (POC) configuration and the MAX Fault-tolerant dataflow multiprocessor, were evaluated. The main observation was that the AIPS design is biased towards fault tolerance and may not be an ideal architecture for planetary and deep space probes due to high cost and complexity. The MAX concepts appears to be a promising candidate, except that more detailed information is required. The feasibility for adding neural computation capability to this architecture needs to be studied. Key impact issues for architectural design of computing systems meant for planetary missions were also identified

Open predicate path expressions for distributed environments: notation, implementation, and extensions

This dissertation introduces open predicate path expressions --a non-procedural, very-high-level language notation for the synchronization of concurrent accesses to shared data in distributed computer systems. The target environment is one in which resource modules (totally encapsulated instances of abstract data types) are the basic building blocks in a network of conventional, von Neumann computers or of functional, highly parallel machines. Each resource module will contain two independent submodules: a synchronization submodule which coordinates requests for access to the resource\u27s data and an access-mechanism submodule which localizes the code for operations on that data;Open predicate path expressions are proposed as a specification language for the synchronization submodule and represent a blend of two existing path notations: open path expressions and predicate path expressions. Motivations for the adoption of this new notation are presented, and an implementation semantics for the notation is presented in the form of dataflow graphs;An algorithm is presented which will automatically synthesize an open predicate path expression into a dataflow graph, which is then implemented by a network of communicating submodules written in either a sequential or an applicative language. Finally, an extended notation for the synchronization submodule is proposed, the purpose of which is to provide greater expressive power for certain synchronization problems which are difficult to specify using path expressions alone

Designing a flexible compilation framework for cal language

The CAL, created as a part of the Ptolemy II project, is an open source actor-based data-flow language. Some of its contributors are Xilinx, Ericsson research, and the MPEG-consortium. More information about CAL can be found at opendf.org. Today there exist several back ends for CAL, all share a common front end, which translates the CAL language to an intermediate format called XLIM. The back end then translates XLIM to the target language, i.e., VHDL, C, and ARM (C code and run-time environment). The existing tool chains are based on XML and XML transformations (XSLT), but the expressiveness of the XSLT language limits which transformations can be carried out. Furthermore, some parts of the existing front end are note

A social-engineering-centric data collection initiative to study phishing

Phishers nowadays rely on a variety of channels, ranging from old-fashioned emails to instant messages, social networks, and the phone system (with both calls and text messages), with the goal of reaching more victims. As a consequence, modern phishing became a multi-faceted, even more pervasive threat that is inherently more difficult to study than traditional, email-based phishing. This short paper describes the status of a data collection system we are developing to capture different aspects of phishing campaigns, with a particular focus on the emerging use of the voice channel. The general approach is to record inbound calls received on decoy phone lines, place outbound calls to the same caller identifiers (when available) and also to telephone numbers obtained from different sources. Specifically, our system analyzes instant messages (e.g., automated social engineering attempts) and suspicious emails (e.g., spam, phishing), and extracts telephone numbers, URLs and popular words from the content. In addition, users can voluntarily submit voice phishing (vishing) attempts through a public website. Extracted telephone numbers, URLs and popular words will be correlated to recognize campaigns by means of cross-channel relationships between messages