A Novel Measurement-Based Call Admission Control Algorithm for Wireless Mobility Networks under Practical Mobility Model

The General Packet Radio Service (GPRS) provides the predictive services for the users by applying the similar algorithm in the QoS management mechanisms used by the ATM. Research shows that a connective Measurement-Based Admis- sion Control (MBAC) algorithm is more adaptable to and efficient for the GPRS network than other admission control algorithms. Based on sufficient analysis of the characteristics of GPRS, a MBAC algorithm is presented which is suitable for GPRS using a worst-case delay calculation model with a priority queue, and equivalent leaky bucket approximation and delay normalization. The most char- acteristic of this algorithm is that it used both bandwidth and delay at the same time for the control admission. The emulation result shows that this algorithm can achieve a rate of as high as 80% resource utilization while satisfying the requirements of GPRS QoS.

Elastic threshold-based admission control for QoS satisfaction with reward optimization for servicing multiple priority classes in wireless networks

This paper presents a new approach to prediction of resource demand for future handoff calls in multimedia wireless IP networks. Our approach is based on application of multi‐input‐multi‐output (MIMO) multiplicative autoregressive‐integrated‐moving average (ARIMA) (p,d,q)x(P,D,Q)S models fitted to the traffic data measured in the considered cell itself and on the new call admission control (CAC) algorithm that simultaneously maximizes the system throughput while keeping the handoff call dropping probability (CDP) below the targeted value. The main advantages of the proposed approach are the following: first, the proposed multi‐variable prediction method gives on average better predictions (i.e. narrower prediction confidence interval) for realistic traffic situations, which results in lower new call blocking probability (CBP) at the targeted handoff CDP and second, the model is simple to implement since it does not require communication among the adjacent cells. Simulation results show the superiority of the proposed MIMO prediction approach combined with the proposed call admission control algorithm for some typical nonstationary situations in comparison with univariate models. Copyright © 2004 John Wiley & Sons, Ltd.

The purpose of call admission control in Integrated Services Networks is to offer a guarantee that Quality of Service (QoS) bounds are not violated due to the admission of new calls into the network. This is typically accomplished using the declared worst-case traffic descriptors for incoming calls, a solution which results in poor bandwidth utilization. A measurement-based admission scheme is an appealing alternative: not only does it offer adaptivity to changing traffic conditions, it also allows statistical multiplexing gains to be exploited. In this paper, we examine the problem of determining which traffic characterization a measurement-based admission control algorithm should require of sources requesting access. Building on the work of Jamin et al. (1995), we also propose an adaptive measurement-based admission control algorithm that simplifies the estimation process, and show that it can achieve a high level of utilization without violating its delay-based QoS guarantees.

In this paper, we propose to design a call admission control algorithm which schedules the channels for real time and non-real time users based on Utility function. In Long Term Evolution (LTE) 3GPP Networks, several works were done on call admission control but these works rarely considers scheduling of resources to the real time and non-real time users. The call requests are classified into new call (NC) request and handoff call (HC) request and the type of services are classified as VoIP and video. Then based upon the received signal strength (RSS) value, the channel is estimated as good channel or bad channel. Resource allocation is made for VoIP users based on traffic density. Then non-VoIP users and the non-real time users are allocated resource blocks using the channel condition based marginal utility function. When there are no sufficient resources to allocate, it allocates the resources of bad channel users there by degrading their service. Thus from our simulation results we show that this admission control algorithm provides channel quality and prioritizes the handover calls over new calls which allocates resources to all kinds of users.

Call admission control for reducing dropped calls in CDMA cellular systems

The crucial issues for service providers in wireless cellular networks include providing guaranteed quality of service (QoS), minimizing dropping rate (DR) for handoff calls, reducing the blocking rate (BR) for new calls and most importantly ensuring efficient utilization of network resources to maximize profits. This paper proposes an adaptive call admission control (CAC) algorithm for a wideband code division multiple access (WCDMA) network. The proposed algorithm utilizes three major concepts: cell breathing by considering the distance of a new and handoff call from a base station, bandwidth degradation of multimedia calls to provide priority for voice and video calls and transfer of ongoing calls to other cells to provide the highest priority to voice calls. This work is useful in the case when a voice or video call cannot be accepted into a cell due to unavailability of bandwidth and also when a new or handoff voice call cannot be accepted because the cell has already reached its maximum number of calls. Simulation results are presented for relations between call blocking, dropping probability and bandwidth utilization for different types of traffic (i.e. multimedia, video and voice calls).

Traditional approach for data transmission in wireless networks with the shared medium, e.g., 802.11 standard family, incurs significant overheads to transmit messages in multiple source - multiple destination (MSMD) schemes. Network coding is new paradigm that increases effectiveness of transmissions in a wireless network with the shared medium and MSMD. We have considered the results of the emulation with COPE-like network coding and various Transmission Control Protocol (TCP) congestion control algorithms in wireless networks. In emulated scheme two nodes stream data to each other through bottleneck relay node. BBR TCP protocol showed the best results in this relaying scheme with enabled COPE-like network coding.

This paper proposes a novel call admission control (CAC) algorithm and develops a two-dimensional markov chain processes (MCP) analytical model to evaluate its performance for heterogeneous wireless network. Within the context of this paper, a hybrid UMTS-WLAN network is investigated. The designed threshold-based CAC algorithm is launched basing on the user’s classification and channel allocation policy. In this approach, channels are assigned dynamically in accordance with user class differentiation. The two-dimensional MCP mathematical analytic method reflects the system performance by appraising the dropping likelihood of handover traffics. The results show that the new CAC algorithm increases the admission probability of handover traffics, while guarantees the system quality of service (QoS) requirement.KeywordsCall admission controlhandovertwo-dimension markov chainheterogeneous networksdropping probability

¿Pseudo congestion¿ phenomenon may happen in heterogeneous networks due to the asymmetry of service resource requirements. A new Call Admission Control (CAC) algorithm based on Inter-Link Load Balance (ILLB) is proposed to avoid the pseudo congestion as well as to improve the network performance. This algorithm aims to balance the Uplink (UL) load and Downlink (DL) load of the heterogeneous networks. Simulation results show that the presented new CAC can decrease the blocking rate effectively compared with the traditional load balance (LB) algorithms.

This paper presents new distributed power and admission control algorithms for ad-hoc wireless networks in random channel environments. Previous work in this area has focused on distributed control for ad-hoc networks with fixed channels. We show that the algorithms resulting from such formulations do not accurately capture the dynamics of a time-varying channel. The performance of the network in terms of power consumption and generated interference can be severely degraded when power and admission control algorithms that are designed for deterministic channels are applied to random channels. In particular, some well-known optimality results for deterministic channels no longer hold. In order to address these problems we propose a new criterion for power optimality in ad-hoc wireless networks. We then show that the optimal power allocation for this new criterion can be found through an appropriate stochastic approximation algorithm. We also present a modified version of this algorithm for tracking nonstationary equilibria, which allows us to perform admission control. Ultimately, the iterations of the stochastic approximation algorithms can be decoupled to form fully distributed on-line power and admission control algorithms for ad-hoc wireless networks with time-varying channels.

In this paper, we develop call admission control algorithms for SIR-based power-controlled DS-CDMA cellular networks. We consider networks that handle both voice and data services. When a new call (or a handoff call) arrives at a base station requesting for admission, our algorithms will calculate the desired power control setpoints for the new call and all existing calls. We will provide necessary and sufficient conditions under which the power control algorithm will have a feasible solution. These conditions are obtained through deriving the inverse of the matrix used in the calculation of power control setpoints. If there is no feasible solution to power control or if the desired power levels to be received at the base station for some calls are larger than the maximum allowable power limits, the admission request will be rejected. Otherwise, the admission request will be granted. When higher priority is desired for handoff calls, we will allow different thresholds (i.e., different maximum allowable power limits) for new calls and handoff calls. We will develop an adaptive algorithm that adjusts these thresholds in real-time as environment changes. The performance of our algorithms will be shown through computer simulation and compared with existing algorithms.

In wireless communications networks with multiple service classes (SCs) of calls, call admission control (CAC) schemes is an essential radio resource management (RRM) function for networks consistency. Apart from the calculation of the call blocking probability (CBP) appropriate criteria and metrics should be considered to evaluate the efficiency of various schemes. Fairness among different services is an important efficiency criterion for CAC in wireless networks with multimedia services while throughput is an efficiency criterion of general validity. In the present paper, four CAC schemes based on guard channel algorithms are proposed for multiclass services, offering priority to real time service class calls while ensuring a certain level of quality of service (QoS). The proposed schemes investigate the CAC problem in terms of ongoing users and occupied channels. Fairness among calls of different classes is evaluated and the network performance is compared with respect to input load.

The multimedia stream traffic in a broadband mobile network has the ability of adapting its bandwidth request, which makes the capacity of the network elastic. The call admission control (CAC) algorithm of an adaptive service should keep the user's bandwidth degradation period below a certain upper limit, at the same time, admit as many of the call requests as possible. A new CAC algorithm based on a sliding window is introduced. The simulation result shows that this algorithm can improve the system capacity effectively and can protect the QoS of the adaptive service.

We propose a routing mechanism with distributed Call Admission Control (CAC) algorithms for Mobile Ad hoc Networks (MANET) based on IEEE 802.11e EDCA MAC protocol. A new flow can be admitted by the network only if it can find a path to sustain its traffic. Bloom filter is used here to detect the flows via each node, and the CAC routing decisions are made according to the number of flows of each node. Simulation results show that with our distributed CAC algorithm, the existing flows can be well protected in multi-hop MANET; the new added flows can make good use of the bandwidth resources without affecting the neighbor flows. Due to the space-efficient character of Bloom filter, it can be properly used in MANET, whose nodes have limited storage space and computational ability.