Traditional Admission Control Research Articles

Fast Admission Control and Power Optimization With Adaptive Rates for Communication Fairness in Wireless Networks

Along with the exponentially increasing quantity of intelligent terminals connected to the Internet, the spectrum competition among users becomes more and more severe in wireless networks. The network have not the ability to satisfy all communication requirements due to the significantly increasing users and demanded rates. Energy-aware admission control has been proved to be an efficient way to tackle the infeasibility caused by the severe spectrum competition among users. However, the traditional admission control is limited by gradually removing chosen users, and pays less attention to the fairness. In this article, we elaborate the concept of the fairness in a max-min optimization problem with respect to the transmission rates, by leveraging the model of bit error rates with $Q$ Q -function for general fading communications. Then, we make use of the max-min rate fairness to smartly determine the subset of users to be admitted in wireless networks. Meanwhile, the overall energy consumption is minimized and the network fairness is guaranteed. In particular, the algorithms can tackle more than one user at each iteration. Numerical evaluations show the effectiveness of the algorithms.

FQAC: a soft admission control scheme for high quality video delivery over cognitive radio wireless networks

Video transmission over error-prone cognitive radio wireless networks is a challenging task. In much of the traditional tight admission control algorithms for video cognitive users (CUs) in cognitive networks, CUs are admitted sequentially based on the strict quality of service and interference constraints imposed on the cognitive and primary users respectively. The sequential admittance of CUs may impose some form of the queuing delay for time-sensitive CUs which may be unacceptable. On the other hand, traditional admission control schemes do not consider the quality of experience of video users for admitting newly incoming ones. For addressing these issues and obtaining a more flexible quality-centric admission control policy by which the admission system can admit eligible cognitive users in parallel, and to cope with uncertainties in the acceptable levels of the video quality for different CUs (which may use different softwares/hardwares with different capabilities) and interference levels imposed on the primary users, a soft admission control (SAC) technique (named FQAC) is proposed by which the admission probability level for the parallel CUs can intelligently be controlled based on some linguistic input variables. Numerical analysis has been performed to validate the efficiency of the proposed quality-centric SAC mechanism in sparse and dense networking scenarios.

Class Based and Shared Resources Access Control for Distributed Video-on-Demand System

We are proposing an efficient admission control policy for Video-on-Demand (VOD) system. Traditional Admission control system uses either threshold or resource capacity to accept or reject any incoming request. The distinction of the proposed scheme from the previous work includes: (1) a new concept of integrating the both schemes (shared resource admission control and class base admission control) into one system, is introduced (2) another new concept of Probability, is introduced to access the shared resource (Ports, Bandwidth). In the proposed system, total capacity of VOD server (ports) is partitioned equal to the number of classes plus shared area. When a request arrives at VOD server, it will be admitted if there is capacity to its corresponding partition, otherwise we will check the capacity of shared area and admit it with some probability. If there is no capacity in shared area or no probability, the request will be rejected. The evaluation of the proposed system is done by the simulation model. Numbers of blocked requests are calculated for performance measure. It is observed from the simulation results that proposed admission control policy not only improves the performance of high-priority classes but also reduces a lot the total number of rejected requests.

A fuzzy admission control scheme for high quality video delivery over underlay cognitive radio

In much of the traditional tight admission control algorithms for video cognitive users in cognitive networks, cognitive users are admitted sequentially based on the strict quality of service and interference constraints imposed on the cognitive and primary users respectively. The sequential admittance of cognitive users may impose some form of the queuing delay for time-sensitive cognitive users which may be unacceptable. On the other hand, traditional admission control schemes do not consider the quality of experience (QoE) of video users for admitting newly incoming ones. For addressing these issues and obtaining a more flexible quality-centric admission control policy by which the admission system can admit eligible cognitive users in parallel, and to cope with uncertainties in the acceptable levels of the video quality for different cognitive users (which may use different software/hardware with different capabilities) and interference levels imposed on the primary users, a soft admission control (SAC) technique (named FQAC) is proposed by which the admission probability level for the parallel cognitive users can intelligently be controlled based on some linguistic input variables. Numerical analysis has been performed to validate the efficiency of the proposed quality-aware SAC mechanism.

Design and Analysis of the Gateway Relocation and Admission Control Algorithm in Mobile WiMAX Networks

The WiMAX Forum has defined a two-tiered mobility management to minimize handover delay and packet loss. However, it leads to another problem: When to perform ASN GW relocation? The standards only define the ASN GW relocation procedures without specifying when the ASN GW relocation should be performed. It is left for vendors and operators to develop their own proprietary solutions. In this paper, we propose an algorithm, which incorporates traditional Admission Control (AC) and Wiener Process (WP)-based prediction algorithms to determine when to carry out ASN GW relocation. We further develop an analytical model to analyze the proposed algorithm. Simulations are also conducted to evaluate the performance of the proposed algorithm. The results show that the proposed algorithm can improve the performance significantly in terms of blocking probability, dropping probability, average serving rate, and average signaling overhead.

QoS-aware bandwidth allocation and admission control in IEEE 802.16 broadband wireless access networks: A non-cooperative game theoretic approach

In this paper, we propose an adaptive bandwidth allocation and admission control mechanism based on game theory for IEEE 802.16 broadband wireless networks. A non-cooperative two-person non-zero-sum game is formulated where the base station and a new connection are the players of this game. The solution of the game formulation provides not only the decision on accepting or rejecting a connection, but also the amount of bandwidth allocated to a new connection (if admitted). A queueing model considering adaptive modulation and coding in the physical layer is used to analyze quality of service (QoS) performances, namely, the delay performance for real-time and the throughput performance for non-real-time polling services and best effort service. This queueing model is used by the proposed bandwidth allocation and admission control mechanism to ensure that the utilities for both the base station and the new connection are maximized. The performance of the proposed scheme is evaluated by simulation and compared with that of each of the traditional admission control with static and adaptive bandwidth allocation schemes.

A structural comparison of measurement-based admission control algorithms

Measurement-based admission control (MBAC) algorithm is designed for the relaxed real-time service. In contrast to traditional connection admission control mechanisms, the most attractive feature of MBAC algorithm is that it does not require a prior traffic model and that is very difficult for the user to come up with a tight traffic model before establishing a flow. Other advantages of MBAC include that it can achieve higher network utilization and offer quality service to users. In this article, the study of the equations in the MBAC shows that they can all be expressed in the same form. Based on the same form, some MBAC algorithms can achieve same performance only if they satisfy some conditions.

Revenue maximizing admission control policies for shared IT infrastructures

IT service providers are increasingly hosting different services of different customers on a shared IT infrastructure. While this fosters utilization of hardware infrastructure, system malfunctions, unexpected service behaviour or peak demands for one or more services may exploit resource pools (CPU, I/O, main memory, bandwidth etc.), entailing rejection of service requests. In this paper we describe models for dynamic admission control on shared infrastructures. The admission control model decides whether to accept, buffer or reject a service request based on the revenue, Service Level Agreements (SLAs) and its resource demand in comparison to the actual workload to maximize overall revenue. Simulations of a media streaming infrastructure have been used for evaluation and comparison with traditional admission control policies.

Admission Control Algorithms for Revenue Optimization with QoS Guarantees in Mobile Wireless Networks

We propose and analyze call admission control algorithms integrated with pricing for revenue optimization with QoS guarantees to serve multiple service classes in mobile wireless networks. Traditional admission control algorithms make acceptance decisions for new and handoff calls to satisfy certain QoS constraints such as the dropping probability of handoff calls and the blocking probability of new calls being lower than a pre-specified threshold. We analyze a class of partitioning and threshold-based admission control algorithms that make acceptance/rejection decisions not only to satisfy QoS requirements but also to optimize the revenue of the system by taking prices and arrival/departure information of service calls into account. We show that for a "charge-by-time" pricing scheme, there exist optimal resource allocation settings under which the partitioning and threshold-based admission control algorithms would produce the maximum revenue obtainable by the system without sacrificing QoS requirements. Further, we develop a new hybrid admission control algorithm which outperforms both partitioning and threshold-based admission control algorithms over a wide range of input parameters characterizing the operating environment and service workload conditions. Methods for utilizing of the analysis results for realtime admission control for revenue optimization with QoS guarantees are described with numerical data given to demonstrate the applicability.

Resynchronization and Controllability of Bursty Service Requests

There is an increasing prevalence of interactive Web sessions in the Internet. These are mostly short-lived TCP connections that are delay-sensitive and have transfer times dominated by TCP backoffs, if any, during connection establishment. Unfortunately, arrivals of such connections at a server tend to be bursty, and can trigger multiple retransmissions, resulting in long average client-perceived delays. Traditional traffic control mechanisms, such as token bucket filters, are designed to complement admission control mechanisms, by regulating throughput, bounding service times, and protecting systems from overload. However, they cannot control connection-establishment delays, and thus, do not provide effective control of client-perceived delays. We first present the surprising discovery of a resynchronization property of retransmitted requests that exacerbates client-perceived delays when traditional control mechanisms are used. Then, we introduce a novel, multistage filtering scheme called Abacus Filters (AFs) that limits the client-perceived delay while maximizing server throughput even in the case of bursty connection arrivals. Analysis of delay-control properties of various filtering mechanisms is presented, along with a detailed performance evaluation. AFs are shown to provide tight delay control and better complement traditional admission control policies.

Fixed Versus Adaptive Admission Control in Direct Broadcast Satellite Networks With Return Channel Systems

In this paper, as part of the adaptive resource allocation and management (ARAM) system (Alagoz, 2001), we propose an adaptive admission control strategy, which is aimed at combating link congestion and compromised channel conditions inherent in multimedia satellite networks. We present the performance comparisons of a traditional (fixed) admission control strategy versus the new adaptive admission control strategy for a direct broadcast satellite (DBS) network with return channel system (DBS-RCS). Performance comparisons are done using the ARAM simulator. The traffic mix in the simulator includes both available bit rate (ABR) traffic and variable bit rate (VBR) traffic. The dynamic channel conditions in the simulator reflect time variant error rates due to external effects such as rain. In order to maximize the resource utilization, both for fixed and adaptive approaches, assignment of the VBR services are determined based on the estimated statistical multiplexing and other system attributes, namely, video source, data transmission, and channel coding rates. In this paper, we focus on the admission control algorithms and assess their impact on quality-of-service (QoS) and forward link utilization of DBS-RCS. We show that the proposed adaptive admission control strategy is profoundly superior to the traditional admission control strategy with only a marginal decrease in QoS. Since the ARAM system has several parameters and strategies that play key roles in terms of the performance measures, their sensitivity analysis are also studied to verify the above foundations.

Towards efficient decision rules for admission control based on the many sources asymptotics

This paper introduces new admission criteria that enable the use of algorithms based on the many sources asymptotics in real-life applications. This is achieved by a significant reduction in the computational requirements and by moving the computationally intensive tasks away from the timing-sensitive decision instant. It is shown that the traditional overflow probability type admission control method can be reformulated into a bandwidth requirement type and into a buffer requirement type method and that these methods are equivalent when used for admission control. The original and the two proposed methods are compared through the example of fractional Brownian motion (fBm) traffic.

Measurement‐based admission control for bufferless multiplexers

AbstractIn this paper we study measurement‐based admission control for bufferless multiplexing, which is very attractive for real‐time traffic. We first discuss a novel large deviations (LD) approach to measurement‐based admission control. We then provide an extensive review of the existing literature on measurement‐based admission control. We conduct simulation studies with traces of MPEG 1 encoded movies to compare the performance of the admission rules in the literature with that of our large deviations approach. We demonstrate that our LD approach achieves higher link utilizations. Finally, we compare the performance of measurement‐based admission control with that of traditional admission control, which relies ona prioritraffic descriptors. Our numerical work indicates that measurement‐based admission control achieves significant gains in link utilizations over traditional admission control. Copyright © 2001 John Wiley & Sons, Ltd.

Novel optimal real-time admission control and buffer management for the Video-On-Demand (VOD) service

In order to meet the Quality of Service (QoS) requirements of the VOD service, and, on the other hand, to maximize the system throughput (revenue), it is essential that the video call request admission control algorithm be carefully designed. In this paper, in addition to the Single Segment (SS) admission control first described in [7], we propose two new types of admission control schemes called Segmental Re?tuned (SR) admission control and Multiple Segment (MS) admission control for variable?bit?rate video streams under various video server architectures. The basic approach to the algorithm development is first to formulate each problem as a mathematical problem and then to identify special structures and properties for such formulations so that optimal real?time algorithms can be developed. In computational experiments, it is shown that the proposed algorithms for the considered video server architectures, compared with the traditional admission control scheme based upon the peak frame size, typically achieve over 175---200% improvement in the system throughput. In addition, the new proposed MS scheme performs 5---25% better than SS and SR schemes.

Performance analysis of admission control algorithms based on reward optimization for real-time multimedia servers

We propose and analyze a class of admission control algorithms based on reward optimization for multimedia servers designed to provide on-demand services to clients in an environment where workload characteristics of clients can change dynamically. These admission control algorithms are developed based on two strategic choices, namely, “deterministic” or “best-effort” regarding quality of service (QoS) control, and “priority-reservation” or “no priority-reservation” regarding reservation control. We first formulate the design of admission control algorithms for real-time multimedia servers as a reward optimization problem, with the “reward” referring to the value which the system receives after servicing prioritized clients based on the QoS requested and delivered. Then, we derive closed-form solutions for the reward rate expressions which the system can possibly obtain as a result of applying these admission control algorithms and validate the analytical results with a simulated VBR video server. A physical interpretation is given for the best combination of strategic choices under which the system can obtain the best reward as a function of workload and cost characteristics of the clients. We demonstrate that the reward value which the system receives under our proposed admission control algorithms at optimizing conditions can be much higher than those under traditional admission control algorithms which do not consider reward optimization.

Threshold-Based Admission Control Policies for Multimedia Servers

Traditional admission control algorithms for on-demand multimedia servers concern the acceptance decisions for new clients' requests so as to guarantee that continuous services to all clients are executed. These algorithms determine whether a new client can be accepted, based on the consideration whether the underlying hardware can satisfy the quality of service (QoS) requirements of admitted client requests. In this paper, we consider a richer class of admission control algorithms that make acceptance/rejection decisions not only to satisfy the hardware requirements of client requests but also to optimize the reward of the system based on a performance criterion as it services clients of different priority classes. We divide the server capacity into a number of ‘priority threshold values’ based on which the system decides whether to accept clients of different priority classes dynamically in order to maximize the system value. The resulting threshold-based admission control algorithm is developed based on the idea that admission control can be driven not only by hardware requirements, but also by knowledge regarding the workload characteristics of client requests, thus allowing the system to adjust dynamically the threshold values in response to changes in client workload characteristics. We derive a close-form expression for the value which the system can obtain when operating under the threshold-based algorithm as a function of model parameters, and discuss how the server can utilize the analytical solution at run time so as to maximize the system value dynamically without violating clients' continuity requirements.