Call Admission Control Schemes : A Review
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paper_title: Stochastic theory of a data-handling system with multiple sources

paper_content:

In this paper we consider a physical model in which a buffer receives messages from a finite number of statistically independent and identical information sources that asynchronously alternate between exponentially distributed periods in the ‘on’ and ‘off’ states. While on, a source transmits at a uniform rate. The buffer depletes through an output channel with a given maximum rate of transmission. This model is useful for a data-handling switch in a computer network. The equilibrium buffer distribution is described by a set of differential equations, which are analyzed herein. The mathematical results render trivial the computation of the distribution and its moments and thus also the waiting time moments. The main result explicitly gives all the system's eigenvalues. While the insertion of boundary conditions requires the solution of a matrix equation, even this step is eliminated since the matrix inverse is given in closed form. Finally, the simple expression given here for the asymptotic behavior of buffer content is insightful, for purposes of design, and numerically useful. Numerical results for a broad range of system parameters are presented graphically.
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paper_title: Optimal burst level admission control in a broadband network

paper_content:

In a broadband ATM network the traffic of a virtual circuit is denned at the cell, burst and call levels. All virtual circuits sharing the resources of a switch are statistically multiplexed at the cell level. In this paper the issue of how to control the admission of bursts of a particular virtual circuit is analyzed. It is demonstrated that under two optimization criteria, the optimal burst level admission control of a virtual circuit is a window control. This result suggests that while the cells of all virtual circuits sharing the resources of a switch should be serviced using the statistical multiplexing technique, at the burst level, the total number of bursts of a particular virtual circuit admitted inside the network should be monitored and controlled in such a way that the number of bursts does not exceed a given upper bound, which is the quota for that particular virtual circuit.
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Title: Call Admission Control Schemes: A Review

Section 1: Introduction
Description 1: Write an overview of the existing infrastructure for public networking, the evolution from N-ISDN to B-ISDN, and the concept of Call Admission Control (CAC) in the context of ATM networks.

Section 2: Statistical allocation
Description 2: Describe the concept of statistical allocation, its benefits for bursty sources, the challenges involved, and various bandwidth allocation algorithms proposed for this scheme.

Section 3: Characterization of an arrival process
Description 3: Discuss different models used for traffic characterization in ATM networks, including Poisson, Bernoulli, Interrupted Poisson/Bernoulli Processes, and Markov Modulated Processes.

Section 4: Classification of call admission schemes
Description 4: Provide a classification of various CAC schemes as proposed in the literature, detailing the underlying principles such as equivalent capacity, heavy traffic approximation, upper bounds of cell loss probability, and fast buffer/bandwidth allocation.

Section 5: Time windows
Description 5: Examine the concept of time-window-based CAC schemes, explaining the working mechanisms like frame-based transmission limits and credit-based flow control, along with their pros and cons.

Section 6: Equivalent capacity
Description 6: Explain the notion of equivalent capacity for call admission, its derivation for single and multiple sources, and the approximation methods used to simplify its computation.

Section 7: Heavy traffic approximation
Description 7: Describe the heavy traffic approximation method for bandwidth allocation based on the asymptotic behavior of queue-length distribution and its application to CAC.

Section 8: Fast buffer/bandwidth allocation
Description 8: Explore fast buffer/bandwidth allocation schemes designed for bursty sources, detailing specific protocols like step increase/decrease requests and buffer reservation state machines.

Section 9: Other call admission control schemes
Description 9: Review additional dynamic and reactive bandwidth allocation schemes, optimization approaches, neural network-based CAC, and the use of Bayesian decision theory for admission control.

Section 10: Comparison of the performance of some call admission schemes
Description 10: Provide a numerical comparison of CAC schemes like equivalent capacity, heavy traffic approximation, and CLP upper bound, analyzing their performance in various traffic scenarios and buffer sizes.

Section 11: Case 1: Relatively Small Buffer Size
Description 11: Present a specific case study analyzing the performance of CAC schemes under small buffer sizes, discussing admission regions and statistical gains.

Section 12: Case 2: Relatively Large Buffer Size
Description 12: Discuss another case study with large buffer sizes, comparing admission regions and statistical gains for different CAC methods.

Section 13: Effect of the Buffer Size
Description 13: Study the sensitivity of CAC schemes to changes in buffer size, highlighting key findings and observations.

Section 14: Effect of the Required Cell Loss Probability
Description 14: Investigate how varying the required cell loss probability impacts the performance of CAC schemes, presenting detailed insights and results.

Section 15: Effect of the Ratio of the Buffer Size to the Mean Burst Length
Description 15: Analyze the effect of the ratio of buffer size to mean burst length on CAC schemes, noting significant observations and implications for achieving statistical gain.