Next generation aircraft computer systems require a major advance in system design practice and associated methods of analysis compared to even the most modern aircraft systems now in service. As well as the ongoing need to demonstrate predictable, real-time behaviour for a wide range of safety critical and mission critical applications, a significant improvement in flexibility is required in o...

It is known that a threshold policy (or trunk reservation policy) is optimal for Erlang’s loss system under certain assumptions. In this paper we examine the robustness of this policy under departures from the standard assumption of exponential service times (call holding times) and give examples where the optimal policy has a generalized trunk reservation form.

Multimedia applications require operating systems that support time-constrained data types such as digital audio and video. These continuous media [1] demand timely service from the system, and time-sharing scheduling algorithms are not sufficient. Furthermore, simple fixed priority scheduling, used in many hard real-time systems, does not necessarily guarantee the successful execution of arbit...

DTM is a fiber-optic network, based on bandwidth reservation and with support for dynamic reallocation of bandwidth. It is designed for real-time multimedia applications and for high-speed computer communication. DTM uses a novel medium-access technique and provides a multicast connection-oriented service. Several DTM networks can be connected into one large network. A prototype implementation ...

With information access becoming more and more ubiquitous, there is a need for providing QoS support for communication that spans wired and wireless networks. For the wired side, RSVP/SBM has been widely accepted as a flow reservation scheme in IEEE 802 style LANs. Thus, it would be desirable to investigate the integration of RSVP and a flow reservation scheme in wireless LANs, as an end-to-end...

In recent years, real-time operating systems began to support the resource reservation paradigm. This technique has proved to be very effective in providing QoS to both, real-time and legacy applications, ensuring that the temporal misbehavior of an application does not affect any other (temporal isolation). However, resource sharing in a reservation system is still not well understood, and can...

In resource constrained embedded systems, memory reservation, which provides physically contiguous memory allocation to devices (e.g., video decoder and camera), decreases the memory efficiency of the system. The dedicated use of reserved memory by an owner device makes itself more under-utilized when the device is less frequently used. Previous approaches support on-demand reservation to relax...

We present a new method for determining placements of flexible reservation requests into a schedule. For each considered placement the what-if method inserts a placeholder into the schedule and simulates the processing of batch jobs currently known to the system. Each placement is evaluated wrt. well-known scheduling metrics. This information may be used by a Grid reservation service to choose ...

Effective and efficient Quality of Service (QoS) management is critical for a service grid to meet the requirements of both grid users and service providers. We introduce a scalable framework of service management in grid environment to guarantee the QoS of grid services. Several characters of our framework are 1) grid level resource reservation mechanism to use existing heterogeneous resource ...

Due to the high mobility of low earth orbit (LEO) satellites, there is a significant number of handover attempts in a LEO satellite mobile communication system, causing a high handover failure rate. This paper proposes an Adaptive Channel Reservation Scheme (ACRS) which gives an overall optimal success rate for both handover and new call initialisation. ACRS is able to adapt to the local traffi...