TiltType is a novel text entry technique for mobile devices. To enter a character, the user tilts the device and presses one or more buttons. The character chosen depends on the button pressed, the direction of tilt, and the angle of tilt. TiltType consumes minimal power and requires little board space, making it appropriate for wristwatch-sized devices. But because controlled tilting of one's forearm is fatiguing, a wristwatch using this technique must be easily removable from its wriststrap. Applications include two-way paging, text entry for watch computers, web browsing, numeric entry for calculator watches, and existing applications for PDAs.

Describes SRI International's ERDoS (End-to-end Resource management of Distributed Systems) project. ERDoS is a distributed middleware with comprehensive resource management support, including application scheduling, resource allocation and graceful adaptation. We discuss how we have implemented this resource management as part of the Java Virtual Machine (JVM). We have also provided a resource management application programming interface (API) as a new Java class library. The ERDoS development environment enables nonprogrammers to create complex distributed applications by simply stringing together multiple Java methods. The ERDoS runtime environment utilizes a structuring algorithm to create a distributed Java application dynamically, and then provides allocation, scheduling and content-based, graceful, adaptive QoS support to these applications. We demonstrate the benefits of content-based adaptation and of dynamic structuring of distributed applications, using a set of video applications.

In this paper we describe the implementation of our end-to-end QoS-driven resource management scheme, called ERDoS, within a CORBA-compliant ORB that we call the ERDoS QoS ORB. Unlike other real-time CORBA implementations that focus on real-time support for simple client-server applications, our ERDoS QoS ORB provides end-to-end QoS support (i.e., QoS spanning computer network, and storage resources) to applications, while retaining the benefits of an open distributed object system. Specifically we present three contributions. First, we present a model for describing end-to-end applications as a combination of client-server interactions between CORBA objects. Second, we define a model for relating the user/application level QoS requirements to the corresponding resource demand requirements of these individual CORBA objects. Third, we suggest a framework for performing distributed resource management within the CORBA environment.

An increasing number of applications execute over a set of computing and communication resources and have end-to-end quality of service (QoS) requirements. Given a system and an application with specific flow structure and QoS requirements, this paper describes an integrated QoS-based allocation and routing algorithm that determines which computing and communication resources to utilize for this application. More specifically, the algorithm finds the best flow path for an application, subject to application flow and QoS constraints, so as to optimize system objectives (e.g., minimize total system utilization or balance the load). The paper also introduces a /spl Delta/-optimal algorithm that, relative to the optimal algorithm, significantly reduces the run-time of the algorithm with a minor degradation in the optimality of the solution. The /spl Delta/-optimal algorithm is guaranteed to produce a result that is at most /spl Delta/-units sub-optimal. The paper also analyzes the optimality and run time of the solution as a function of /spl Delta/ for two multimedia scenarios. Rules of thumb for setting /spl Delta/ are also given.

This paper presents an hierarchical end-to-end analysis technique that decomposes the very complex heterogeneous multi-resource scheduling problem into a set of single resource scheduling problems with well defined interactions. We define heterogeneity both in resource types, e.g., CPU, and in scheduling policies, e.g., rate-monotonic scheduling. This analysis technique is one phase of our systems integration framework for designing large-scale, heterogeneous, distributed real-time systems whose timing properties can be strictly controlled and analyzed. This approach, denoted the Distributed Pipelining Framework, exploits the natural pipelining execution pattern found in a large number of continuous (periodic) applications executing over heterogenous resources. A teleconference application is used in this paper to show the utility of the approach.

No abstract available.

This paper describes the distributed pipeline scheduling framework that provides a systematic approach to designing distributed, heterogeneous real-time systems. This paper formalizes distributed pipelining scheduling by providing a set of abstractions and transformations to map real-time applications to system resources, to create highly efficient and predictable systems, and to decompose the very complex multi-resource system timing analysis problem into a set of simpler application stream and single-resource schedulability problems to ascertain that all real-time application timing requirements are met. Distributed pipeline scheduling includes support for distributed, heterogeneous system resources and diverse local scheduling policies, global scheduling policies for efficient resource utilization, flow-control mechanisms for predictable system behaviour, and a range of system reconfiguration options to meet application timing requirements. An audio/video example is used in this paper to demonstrate the power and utility of distributed pipeline scheduling.