Distributed Resource Reservation Research Articles

Distributed Resource Reservation in Hybrid MAC With Admission Control for Wireless Mesh Networks

Providing guaranteed quality of service (QoS) for multimedia applications is a challenging topic in wireless mesh networks (WMNs). This paper proposes a distributed resource reservation (RR) mechanism with novel admission control to guarantee QoS performance of real-time sessions (RTSNs) while improving bandwidth utilization in WMNs. The proposed RR mechanism establishes logical clusters (LCs) for identifying interference relationships between nodes and avoids simultaneous transmissions from interfering nodes. Following the established LCs, a cooperative contention and collision-free channel access is achieved in hybrid medium access control (MAC) for multihop data forwarding in WMNs. To efficiently utilize the scarce resources in a contention-free period, soft and hard resources are reserved for RTSNs according to their QoS demands. This is achieved by a novel admission control algorithm. Furthermore, an analytical model is derived for investigating the RR parameters of the proposed mechanism. Simulation results show that the proposed mechanism guarantees the QoS for RTSNs while improving bandwidth utilization.

A Distributed Resource Reservation Scheme for Handover Failure Reduction

In this letter, we propose a distributed resource reservation strategy for handover failure (HOF) reduction. The network status information that is locally available at each cell is utilized to reserve handover protection (HOP) resources in a dynamic and distributed manner. Each cell transmits downlink traffic using only the reserved HOP resources. Severe interferences to the neighboring cells on non-reserved HOP resources are therefore avoided and HO users associated to the neighboring cells transmitting in the non HOP resources can therefore reduce the HOF significantly. Numerical results following the 3GPP LTE/LTE–A network scenarios show that our proposed strategy can reduce HOF by about 40% to 70% over a conventional random allocation scheme.

Performance analysis of distributed resource reservation in IEEE 802.11e-based wireless networks

Guaranteeing quality of service (QoS) is one of the most critical challenges in IEEE 802.11-based wireless networks. This study proposes an analytical framework to evaluate hybrid medium access control (MAC) scheduling mechanisms with distributed resource reservation (RR), that was proposed for the IEEE 802.11e-enhanced distributed channel access protocol for guaranteeing QoS. The hybrid MAC scheduling mechanisms split the airtime into service intervals with contention-free period for QoS guaranteed real-time sessions (RTSNs), and contention access period for other traffic sessions. The distributed RR ensures that the resources are allocated to RTSNs without the support of a centralised controller–this makes it suitable for ad hoc networking applications. The proposed analytical framework models the QoS (i.e. delay and throughput) performance of RTSNs with dedicated resources in a distributed environment, and also estimates the overall capacity of the network. Moreover, the derived models can be used to investigate the impact of changes to individual system parameters, such as service interval or size of transmission opportunity. The simulation results show that the proposed analytical framework precisely models the QoS performance of RTSNs and predicts the optimum resource allocation for improved network capacity.

Routing and Wavelength Assignment Problem in PCE-Based Wavelength-Switched Optical Networks

As a key problem in wavelength-switched optical networks (WSONs), in which wavelengths are the most important resources, the routing and wavelength assignment (RWA) problem has been researched extensively. Due to the advantages of path computation in multilayer and multidomain networks, especially in multiconstraint scenarios, the path computation element (PCE) has been introduced into WSONs, which provides a better approach to the solution of the RWA problem in WSONs. This paper focuses on the RWA problem in PCE-based WSONs. A PCE-based routing framework and two PCE-based routing models are first designed, and then two distributed resource reservation schemes based on forward reservation protocol (FRP) and backward reservation protocol (BRP) are proposed and simulated in a PCE-based WSON. Finally, eight PCE-based RWA schemes are proposed in WSONs, the performances of which have been investigated and validated using the discrete event simulation tool OMNeT++. Numeric results show that the RWA (first-fit) scheme has the best performance in terms of blocking probability and average delay time.

Extending EDCA with distributed resource reservation for QoS guarantees

In this paper we describe how the contention-based medium access mechanism of 802.11e, EDCA, can be enhanced in order to allow stations to reserve medium access for their real-time applications with QoS requirements. We present our proposed scheme, which is called EDCA with resource reservation (EDCA/RR), and describe how it can be extended in order to be used in wireless multi-hop networks. EDCA/RR operates in a completely distributed manner and manages to provide deterministic, contention-free medium access, making it an attractive scheme for wireless networks.

Special issue: QoS, control, and security in next generation networks

In the NGN initiative, the design of future networks should be driven by services in a top down manner. Services will be typically provided over connections which may straddle different transport networks and network providers, and satisfy security and quality of service constraints. This special issue focuses on some of the aspects of the Next Generation Networks. The main mechanism for delivering services is the Service-Oriented Architecture (SOA). In the paper “Resource Optimization and Security in Enterprise Service Computing”, K. Xiong and H. Perros present a framework for trustworthy Web-based enterprise services and an analytic method for resource allocation within such systems subject to percentile end-to-end delays and server availability constraints. Setting up connections with quality of service guarantees is part of the NGN requirements. To that effect, A. Hamidian, and U. Korner in their paper “Extending EDCA With Distributed Resource Reservation For QoS Guarantees” propose an enhancement of EDCA, the contention-based medium access mechanism of 802.11, so that multimedia applications with QoS requirement can reserve medium access time. The proposed scheme is further extended to a multi-hop wireless network. Wireless technologies can facilitate service delivery since they will offer large bandwidth at low prices. In the paper “A Piloting Plane For Controlling Wireless Applications”, the authors T. Bullot, D. Gaiti, G. Pujolle, and H. Zimmermann, propose an automatic pilot system that can be used to

A Contention Detection Scheme for Lightpath Restoration in GMPLS Networks

In wavelength-routed networks based on GMPLS control plane, lightpaths can be dynamically established upon distributed resource reservation performed by RSVP-TE protocol. Resource contentions may occur in the backward signaling when two or more RSVP-TE instances concurrently attempt to reserve the same wavelength (backward blocking). This paper proposes a contention detection (CD) scheme, compliant with RSVP-TE, that detects possible resource contentions and adapts the wavelength selection strategy accordingly. CD scheme is applied to restoration of the lightpaths disrupted by a single-link failure. Simulation results show that the CD scheme is effective in mitigating the backward blocking and thus the overall blocking.