Resource management in IP-based radio access networks

IP is being considered to be used in the Radio Access Network (RAN) of UMTS. It is of paramount importance to be able to provide good QoS guarantees to real time services in such an IP-based RAN. QoS in IP networks is most efficiently provided with Differentiated services (Diffserv). However, currently Diffserv mainly specifies Per Hop Behaviors (PHB). Proper mechanisms for admission control and resource reservation have not yet been defined. A new resource management concept in the IP-based RAN is needed to offer QoS guarantees to real time services. We investigate the current Diffserv mechanisms and contribute to development of a new resource management protocol. We focus on the load control algorithm [9], which is an attempt to solve the problem of admission control and resource reservation in IP-based networks. In this document we present some load control issues and propose to enhance the load control protocol with the Measurement Based Admission Control (MBAC) concept. With this enhancement the traffic load in the IP-based RAN can be estimated, since the ingress router in the network path can be notified by marking packets with the resource state information. With this knowledge, the ingress router can perform admission control to keep the IP-based RAN stable with a high utilization even in overload situations

Traffic management by using admission control methods in multiple node IMS network

The paper deals with Admission Control methods (AC) as a possible solution for traffic management in IMS networks (IP Multimedia Subsystem) - from the point of view of an efficient redistribution of the available network resources and keeping the parameters of Quality of Service (QoS). The paper specifically aims at the selection of the most appropriate method for the specific type of traffic and traffic management concept using AC methods on multiple nodes. The potential benefit and disadvantage of the used solution is evaluated

Quality Of Service Provisioning Scheme For Real-Time Applications in IEEE 802.11 Wireless Local Area Network

This thesis presents a novel quality of service (QoS) provisioning scheme for realtime applications in IEEE 802.1 1e wireless local area networks (WLAN). The emerging 802.1 1e standard is tackling the exploding volume of traffic in WLANs with a long -term solution based on QoS-architectures. QoS delivers predictability and consistency into existing variability of best-effort delivery system offered in internet protocol (IP) and IEEE 802.11 wireless networks. Service differentiation in WLAN networks is achieved by means of assigning packets (from the network layer) to different access categories (AC), a set of fixed medium access control (MAC) level parameters that defines the priority echelon for each AC. Thus real-time applications are assigned higher priority ACs to ensure better service and to ensure that the delay constraints of these applications are promptly dealt with. An algorithm called Slide and Translate (SNT) is proposed for IEEE 802.1 1 WLANs. The SNT adapts contention parameters of individual ACs based on the network load in a basic service set (BSS). SNT is derived from the observations of the success and failures of previously proposed QoS provisioning schemes. The SNT adapts the backoff interval, minimum contention window (CW,,,) and contention offset (CWOffsetto) ensure the QoS constraints for the different ACs are dealt with. To further understand the SNT, a simple mathematical analysis is presented on the inter-AC differentiation characteristics; subsequently, through simulation it is shown that SNT is able to maintain high medium utilisation over a wide range of offered loads while providing a high degree of isolation (in terms of throughput, delay and frame loss) to high priority traffic. Further to this, an extension to the SNT called SNT-AC is proposed in order to achieve efficient end-to-end resource provisioning. SNT-AC uses an admission control algorithm to restrict flows in and out of the BSS. The admission controller resides in the IP layer and makes decision based on the MAC level feedback. The simulation results indicate that the close coupling QoS coordination can ensure both bandwidth and latency to admitted flows by controlling the effective offered load into the BSS. This guarantees high priority ACs protection against overwhelming traffic in a WLAN. Finally a brief discussion on future directions of WLANs and hardware implementation issues conclude the thesis

Network emulation focusing on QoS-Oriented satellite communication

This chapter proposes network emulation basics and a complete case study of QoS-oriented Satellite Communication

Pre-Congestion Notification (PCN) Architecture

This document describes a general architecture for flow admission and termination based on pre-congestion information in order to protect the quality of service of established, inelastic flows within a single Diffserv domain.\u

Service level agreement framework for differentiated survivability in GMPLS-based IP-over-optical networks

In the next generation optical internet, GMPLS based IP-over-optical networks, ISPs will be required to support a wide variety of applications each having their own requirements. These requirements are contracted by means of the SLA. This paper describes a recovery framework that may be included in the SLA contract between ISP and customers in order to provide the required level of survivability. A key concern with such a recovery framework is how to present the different survivability alternatives including recovery techniques, failure scenario and layered integration into a transparent manner for customers. In this paper, two issues are investigated. First, the performance of the recovery framework when applying a proposed mapping procedure as an admission control mechanism in the edge router considering a smart-edge simple-core GMPLS-based IP/WDM network is considered. The second issue pertains to the performance of a pre-allocated restoration and its ability to provide protected connections under different failure scenarios