Binary Feedback Research Articles

A gradient-based binary feedback scheme for congestion control in computer networks

A gradient-based binary feedback scheme for congestion control in computer networks

A gradient‐based binary feedback scheme for congestion control in computer networks

A gradient‐based binary feedback scheme for congestion control in computer networks

Letter Throughput and Delay Analysis of the Ideal Window

AbstractWe consider the problem of random access communications over a time slotted channel with feedback of infinitely multiplicity at the beginning of each collision resolution interval (CRI), i.e., users know via instantaneous feedback the number of users involved in that collision. Once this is known, the resolution algorithm (CRA) operates with binary (successful / non successful, s/ns) feedback. The analysis of this simple full feedback sensing window random access algorithm, named ideal window stabilized ALOHA, (IWSA), algorithm, provides a throughput of 0.5052 packets/slot. Its delay is also analyzed and compared with similar algorithms.

Performance analysis of rate control scheme considering queue dynamics

In high-speed networks with a large bandwidth-delay product, it is very important to effectively control outstanding packets at the source to avoid network breakdown due to buffer overflows. We propose a new rate-based flow control scheme that aims at control of best-effort traffic instead of guaranteed traffic. Our scheme directly controls the rate at which the source can send packets based on feedback information determined by both the average queue length and queue dynamics (queue increase or decrease). We show through analysis and simulation that the rate and queue fluctuations of the proposed scheme can be made much smaller than those of the conventional scheme, based on binary feedback determined by the average queue length. Therefore, efficient network resource utilization and better throughput/delay performance can be easily achieved.

The RRA-ISA multiple access protocol with and without simple priority schemes for real-time and data traffic in wireless cellular systems

A multiple access protocol, based on a Reservation Random Access (RRA) scheme, is derived for a wireless cellular network carrying real-time and data traffic. Given a TDMA framed channel and a cellular structure, the aim of the protocol is that of maximizing the one-step throughput over an entire frame. This is achieved by deciding on the access rights at the cell base station, which then broadcasts this information at the beginning of the frame. The decision is made on the basis of binary channel feedback information (collision/no collision) over the previous frames, as well as of long term averages of packet generation rates at the mobile stations, assuming independence in the presence of packets at the latter. The resulting protocol has therefore been termed Independent Stations Algorithm (ISA), and the overall scheme RRA-ISA. As in other RRA protocols, time constrained (e.g., voice) traffic operates in a dynamic reservation mode, by contending for a slot in the frame with the first packet of a burst, and then keeping the eventually accessed slot for the duration of the burst; packets of the time constrained traffic unable to access a slot within a maximum delay are dropped from the input buffer. No such constraint is imposed on data traffic. Together with the “basic” version of the access algorithm, three other variants are presented, which exploit three simple different priority schemes in the RRA-ISA “basic” structure, in order to give a prominence to the voice service. The aim of these variants is to improve the performance in terms of the maximum number of stations acceptable in the system, by slightly increasing the data packets delay. All the proposed schemes are analyzed by simulation in the presence of voice and data traffic. Several comparisons show a relevant performance improvement (in terms of data delay and maximum number of voice stations acceptable within a cell) over other protocols that use ALOHA as a reservation mechanism (RRA-ALOHA or PRMA schemes).

Rate control algorithms for the ATM ABR service

AbstractOver the last couple of years both the ATM Forum and ITU‐T have converged on a closed‐loop, feedback based, rate control mechanism as the framework for the Available Bit Rate ATM Transfer Capability. In this framework, an ABR source adapts its transmission rate to changing characteristics of the ATM network by either testing periodically the state of the network or through direct feedback from the network. The state of the network is conveyed to the source either as a simple binary feedback signaling congestion or no congestion, or as an explicit rate indicating the rate at which the source can transmit. In this paper we review the detailed framework for the ABR service standardized by the ATM Forum, the underlying service philosophy and protocol design goals for ABR flow control, and the premises and high‐level performance characteristics for the more promising ABR rate control schemes proposed so far.

Maximum length cellular automaton sequences and its application

In this paper, the maximum length linear binary cellular automaton (CA) sequence is considered. It is shown that all possible maximum length linear binary CA sequences, which are equivalent to maximum length linear binary feedback shift register (LFSR) sequences, can be constructed using linear simple CAs. A table of configurations of the n-cell maximum length simple CAs with its characteristic polynomials is obtained for 76 ⩽ n ⩽ 120. An application of the CAs to stream ciphers is indicated. In other applications, a maximum length LFSR may be replaced by a maximum length linear binary CA.

A MULTIPLE-CHANNEL FREE-ACCESS COLLISION RESOLUTION ALGORITHM BASED CONNECTION REQUEST PROCEDURE FOR LAND MOBILE SATELLITE NETWORKS

A new binary feedback multiple-channel free-access (MCFA) collision resolution algorithm (CRA) based random-access protocol (RAP) is devised to implement the connection request procedure for demand-assigned channel access protocols in land mobile satellite communications networks. The maximum stable throughput of this protocol is derived and is shown to be superior to a previously devised multiple-channel obvious blocked-access CRA based RAP as well as to slotted ALOHA. The throughput performance is also superior to the previously devised multiple-channel window blocked-access CRA based RAP for four or more channels. An exact analysis of the average packet delay for this MCFA CRA based RAP is given and shown to be in excellent agreement with computer simulation results. The protocol is shown to have smaller average delays than the best single-channel free access CRA based RAPs over a wide range of practically usable throughput rates with reasonable delays. This MCFA CRA based RAP was implemented on a channel request protocol test-bed simulator which incorporates the physical link characteristics of the MSAT-X land mobile satellite system. These test-bed simulation results also demonstrate the superiority of this protocol over slotted ALOHA for both error-free channel and mobile facing channel scenarios.

Proportional rate‐based congestion control under long propagation delay

AbstractThe occurrence of congestion severely degrades the performance, especially in high‐speed networks with long propagation delay relative to packet transmission time. This is because it is very likely that a large number of transit packets are flying over such networks at a time and many of them will get lost if they arrive at some congested node. Among ways of controlling traffic to avoid congestion, this paper deals with a class of rate‐based congestion controls (RBCC) which regulate input traffic based on feedback information about network congestion status. Although such mechanisms have been studied recently, the mechanism to be considered, referred to as proportional RBCC, differs from them in that the amount of input traffic allowed to enter in the network is proportional to the network resources available, keeping a closer track of the network resources than the previous ones, where the network status is described by two states, congested or not. The mechanism seeks an optimal network operating point, adapting to dynamic changes of carried traffic. We carry out the stability analysis and the transient analysis of some performance measures related to the proportional RBCC, and also address fairness aspects in providing control to various source‐destination connections, while K. W. Fendick et al. have analysed the stability of a general class of RBCC. Furthermore, by making a comparison between the control mechanism analysed here and the ones based on binary feedback information, we show the effectiveness of the former.

A binary feedback scheme for congestion avoidance in computer networks with a connectionless network layer

We propose a scheme for congestion avoidance in networks using a connectionless protocol at the network layer. The scheme uses feedback from the network to the users of the network. The interesting challenge for the scheme is to use a minimal amount of feedback (one bit in each packet) from the network to adjust the amount of traffic allowed into the network. The servers in the network detect congestion and set a congestion indication bit on packets flowing in the forward direction. The congestion indication is communicated back to the users through the transport level acknowledgement. The scheme is distributed, adapts to the dynamic state of the network, converges to the optimal operating point, is quite simple to implement, and has low overhead while operational. The scheme also addresses a very important aspect of fairness in the service provided to the various sources utilizing the network. The scheme attempts to maintain fairness in service provided to multiple sources. This paper presents the scheme and the analysis that went into the choice of the various decision mechanisms. We also address the performance of the scheme under transient changes in the network and for pathological conditions.

157 Global linearization of finite state machines via feedback control

Abstract In this paper binary finite state machines are described by multilinear state equations using the same algebra as in classical discrete-time systems. This includes, as a special case, systems which are linear in the sense of common algebra. The paper focusses the general multilinear case. The main result is the following: Under specific conditions a multilinear binary feedback law can be constructed such that the over-all system becomes linear in the global sense. Degrees of freedom in the controller equation can be utilized to achieve a pre-specified cyclic operation via eigenvalue assignment. The design procedure is illustrated by an example.

Global Linearization of Finite State Machines Via Feedback Control

In this paper binary finite state machines are described by multilinear state equations using the same algebra as in classical discrete-time systems. This includes, as a special case, systems which are linear in the sense of common algebra. The paper focusses the general multilinear case. The main result is the following: Under specific conditions a multilinear binary feedback law can be constructed such that the over-all system becomes linear in the global sense. Degrees of freedom in the controller equation can be utilized to achieve a pre-specified cyclic operation via eigenvalue assignment. The design procedure is illustrated by an example.

Bounds on the delay distribution of window random-access algorithms

A method for analyzing the delay distribution of window random-access algorithms is presented. The window size is allowed to vary during the operation of the algorithm. It is shown that the quantities of interest in the computation of the delay distribution can be related to the solution of appropriate infinite systems of linear equations. Once the constants and the coefficients of the unknowns of the system are determined, bounds on the solution can be developed by applying previously developed methodologies. The method is applied to the delay distribution analysis of the Capetanakis window random-access algorithm and the part-and-try algorithm, both under binary feedback. >

Multiple-access algorithms for a system with mixed traffic: high and low priority

The author considers a system where a single channel is shared by both high- and low-priority data. He assumes packet transmissions from both data categories and slotted channel. In addition, he assumes binary (collision versus noncollision) feedback per slot, and limited feedback sensing capabilities for all users in the system. He assumes that the high-priority data are generated by a well-defined finite-number user population, while he adopts the limit Poisson user model (infinitely many independent Bernoulli users) for the low-priority traffic. For this system, he proposes and analyzes a transmission algorithm which is a mixture of a deterministic tree search for the high-priority users, and a random-access algorithm for the low-priority traffic. The algorithm is stable for both traffic classes, it guarantees a strict upper bound on the delays of the high-priority packets, and induces good throughput-delay characteristics for the low-priority data. >

Near-optimum control of multiple-access collision channels

A method based on recursive computation of the expected number of attempts and successes during the collision resolution phase of an access control algorithm is introduced for the design of near-optimum control strategies for multiple access collision channels with ternary and binary feedback. With this approach it is possible to circumvent the extremely difficult and still unsolved problem of finding the access control algorithm which achieves the highest throughput by settling for a near-optimum solution. The key to the design of the algorithms is to approximate the originally infinite-dimensional optimization problem by a one-dimensional optimization problem. In the ternary feedback case, the proposed algorithm achieves a throughput virtually identical to the highest throughput reported. Several forms of binary feedback are considered, and algorithms are introduced that achieve the highest throughput reported. >

Sequences and arrays derived from nonprimitive irreducible polynomials

The cycle set structure and correlation properties of the families of sequences generated by autonomous binary and multiple valued linear feedback shift registers are investigated. It is demonstrated that these sequence families arise on the rows and columns of pseudorandom arrays formed by folding certain m sequences over GF(q). Expressions are given for the weights and corre lation values for certain classes of these sequence families. Relevant design data are presented in tabular form.

A multiuser random-access communication system for users with different priorities

A binary feedback collision resolution algorithm is developed for a multiuser random access communication system with nonhomogeneous user population. The user population is split into two classes with different priorities. The throughput and delay analysis of the proposed algorithm are performed, and numerical results are obtained. >

A binary feedback scheme for congestion avoidance in computer networks

We propose a scheme for congestion avoidance in networks using a connectionless protocol at the network layer. The scheme uses a minimal amount of feedback from the network to the users, who adjust the amount of traffic allowed into the network. The routers in the network detect congestion and set a congestion-indication bit on packets flowing in the forward direction. The congestion indication is communicated back to the users through the transport-level acknowledgment. The scheme is distributed, adapts to the dynamic state of the network, converges to the optimal operating point, is quite simple to implement, and has low overhead. The scheme maintains fairness in service provided to multiple sources. This paper presents the scheme and the analysis that went into the choice of the various decision mechanisms. We also address the performance of the scheme under transient changes in the network and pathological overload conditions.

Backlog performance of some controlled slotted ALOHA systems

The backlog performance of the most efficient algorithm used in the controlled slotted Aloha channel is examined by simulation. Some new schemes based on Mikhailov's algorithm are introduced. The simplest to implement need no traffic estimate and have binary feedback. It is found that such schemes also perform very well, giving an acceptable level of throughput at any load below saturation (1/e).

Throughput and delay analysis of free access tree algorithm with minislots

An analysis is made of the throughput and delay performance of two classes of free-access tree algorithms with minislots. In one class, binary feedback information is available in minislots, and in the other, ternary feedback information is available. It is shown that the highest maximum throughput 0.56714 is achieved in the limiting case where the number of minislots in a (large) slot is infinity and minislot overhead is zero. A lower bound of the average transmission delays in these algorithms is analytically derived. The obtained lower bound is also a lower bound of the average delay of the whole class of the free-access algorithms.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>