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136
IPbased Protocols for Mobile Internetworking
, 1991
"... We consider the problem of providing network access to hosts whose physical location changes with time. Such hosts cannot depend on traditional forms of network connectivity and routing because their location, and hence the route to reach them, cannot be deduced from their network address. In this p ..."
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Cited by 196 (4 self)
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We consider the problem of providing network access to hosts whose physical location changes with time. Such hosts cannot depend on traditional forms of network connectivity and routing because their location, and hence the route to reach them, cannot be deduced from their network address. In this paper, we explore the concept of providing continuous network access to mobile computers, and present a set of IPbased protocols that achieve that goal. They are primarily targeted at supporting a campus environment with mobile computers, but also extend gracefully to accommodate hosts moving between different networks. The key feature is the dependence on ancillary machines, the Mobile Support Stations (MSSs), to track the location of the Mobile Hosts. Using a combination of caching, forwarding pointers, and timeouts, a minimal amount of state is kept in each MSS. The state information is kept in a distributed fashion; the system scales well, reacts quickly to changing topologies, and does ...
Reliable Broadband Communication Using a Burst Erasure Correcting Code
 Proceedings of ACM SIGCOMM ’90, Philadelhia, PA
, 1990
"... Traditionally, a transport protocol corrects errors in a computer communication network using a simple ARQ protocol. With the arrival of broadband networks, forward error correction is desirable as a complement to ARQ. This paper describes a simplified ReedSolomon erasure correction coder architect ..."
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Cited by 138 (5 self)
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Traditionally, a transport protocol corrects errors in a computer communication network using a simple ARQ protocol. With the arrival of broadband networks, forward error correction is desirable as a complement to ARQ. This paper describes a simplified ReedSolomon erasure correction coder architecture, adapted for congestion loss in a broadband network. Simulations predict it can both encode and decode at rates up to 1 gigabit per second in a custom 1 micron CMOS VLSI chip. 1.
Architecting Noncooperative Networks
 IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
, 1995
"... In noncooperative networks users make control decisions that optimize their own performance measure. Focusing on routing, we devise two methodologies for architecting noncooperative networks, that improve the overall network performance. These methodologies are motivated by problem settings arising ..."
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Cited by 124 (16 self)
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In noncooperative networks users make control decisions that optimize their own performance measure. Focusing on routing, we devise two methodologies for architecting noncooperative networks, that improve the overall network performance. These methodologies are motivated by problem settings arising in the provisioning and the run time phases of the network. For either phase, Nash equilibria characterize the operating point of the network. The goal of the provisioning phase is to allocate link capacities that lead to systemwide efficient Nash equilibria. In general, the solution of such design problems is counterintuitive, since adding link capacity might lead to a degradation of user performance. We show that, for systems of parallel links, such paradoxes cannot occur and the optimal solution coincides with the solution in the singleuser case. We derive some extensions to general network topologies. During the run time phase, a manager controls the routing of part of the network flow. The manager is aware of the noncooperative behavior of the users and makes its routing decisions based on this information while aiming at improving the overall system performance. We obtain necessary and sufficient conditions for enforcing an equilibrium that coincides with the global systemwide optimum, and indicate that these conditions are met in many cases of interest.
Achieving Network Optima Using Stackelberg Routing Strategies
, 1997
"... In noncooperative networks users make control decisions that optimize their individual performance objectives. Nash equilibria characterize the operating points of such networks. Nash equilibria are generically inefficient and exhibit suboptimal network performance. Focusing on routing, a methodolog ..."
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Cited by 107 (14 self)
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In noncooperative networks users make control decisions that optimize their individual performance objectives. Nash equilibria characterize the operating points of such networks. Nash equilibria are generically inefficient and exhibit suboptimal network performance. Focusing on routing, a methodology is devised for overcoming this deficiency, through the intervention of the network manager. The manager controls part of the network flow, is aware of the noncooperative behavior of the users and performs its routing aiming at improving the overall system performance. The existence of maximally efficient strategies for the manager, i.e., strategies that drive the system into the global network optimum, is investigated. A maximally efficient strategy of the manager not only optimizes the overall performance of the network, but also induces an operating point that is efficient with respect to the performance of the individual users (Pareto efficiency). Necessary and sufficient conditions for...
Pointtopoint connectivity between neuromorphic chips using addressevents
 IEEE Trans. Circuits Syst. II
, 2000
"... Abstract — I discuss connectivity between neuromorphic chips, which use the timing of fixedheight, fixedwidth, pulses to encode information. Addressevents—log2 (N)bit packets that uniquely identify one of N neurons—are used to transmit these pulses in realtime on a randomaccess, timemultiplex ..."
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Cited by 89 (17 self)
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Abstract — I discuss connectivity between neuromorphic chips, which use the timing of fixedheight, fixedwidth, pulses to encode information. Addressevents—log2 (N)bit packets that uniquely identify one of N neurons—are used to transmit these pulses in realtime on a randomaccess, timemultiplexed, communication channel. Activity is assumed to consist of neuronal ensembles—spikes clustered in space and in time. I quantify tradeoffs faced in allocating bandwidth, granting access, and queuing, as well as throughput requirements, and conclude that an arbitered channel design is the best choice. I implement the arbitered channel with a formal design methodology for asynchronous digital VLSI CMOS systems, after introducing the reader to this topdown synthesis technique. Following the evolution of three generations of designs, I show how the overhead of arbitrating, and encoding and decoding, can be reduced in area (from N to √ N) by organizing neurons into rows and columns, and reduced in time (from log2 (N) to 2) by exploiting locality in the arbiter tree and in the row–column architecture, and clustered activity. Throughput is boosted by pipelining and by reading spikes in parallel. Simple techniques that reduce crosstalk in these mixed analog–digital systems are described.
On the existence of equilibria in noncooperative optimal flow control
 Journal of the ACM
, 1995
"... Abstract. The existence of Nash equilibria in noncooperative flow control in a general productform network shared by K users is investigated. The performance objective of each user is to maximize its average throughput subject to an upper bound on its average timedelay. Previous attempts to study e ..."
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Cited by 71 (10 self)
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Abstract. The existence of Nash equilibria in noncooperative flow control in a general productform network shared by K users is investigated. The performance objective of each user is to maximize its average throughput subject to an upper bound on its average timedelay. Previous attempts to study existence of equilibria for this flow control model were not successful, partly because the timedelay constraints couple the strategy spaces of the individual users in a way that does not allow the application of standard equilibrmm existence theorems from the game theory literature. To overcome this difficulty, a more general approach to study the existence of Nash equilibria for decentralized control schemes is introduced. This approach is based on directly proving the existence of a fixed point of the best reply correspondence of the underlying game. For the investigated flow control model, the best reply correspondence is shown to be a function, implicitly defined by means of K interdependent linear programs. Employing an appropriate definition for continuity of the set of optimal solutions of parametrized linear programs, it is shown that, under appropriate conditions, the best reply function is continuous. Brouwer’s theorem implies, then, that the best reply function has a fixed point.
Capacity Allocation under Noncooperative Routing
, 1997
"... The capacity allocation problem in a network that is to be shared by noncooperative users is considered. Each user decides independently upon its routing strategy, so as to optimize its individual performance objective. The operating points of the network are the Nash equilibria of the underlying ro ..."
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Cited by 67 (13 self)
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The capacity allocation problem in a network that is to be shared by noncooperative users is considered. Each user decides independently upon its routing strategy, so as to optimize its individual performance objective. The operating points of the network are the Nash equilibria of the underlying routing game. The network designer aims to allocate link capacities, so that the resulting Nash equilibria are efficient, according to some systemwide performance criterion. In general, the solution of such design problems is complex and at times counterintuitive, since adding link capacity might lead to degradation of user performance. For systems of parallel links, we show that such paradoxes do not occur and that the capacity allocation problem has a simple and intuitive optimal solution, that coincides with the solution in the singleuser case.
A Case for VariableRange Transmission Power
 Control in Wireless Multihop Networks,” Proc. IEEE INFOCOM
, 2004
"... Abstract—In this paper, we investigate the impact of variablerange transmission power control on the physical and network connectivity, on network capacity, and on power savings in wireless multihop networks. First, using previous work by Steele [18], we show that, for a path attenuation factor 2, ..."
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Cited by 47 (2 self)
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Abstract—In this paper, we investigate the impact of variablerange transmission power control on the physical and network connectivity, on network capacity, and on power savings in wireless multihop networks. First, using previous work by Steele [18], we show that, for a path attenuation factor 2, the average range of links in a planar random network of Am2 having n nodes is c ffiffiffi p A n 1. We show that this average range is approximately half the range obtained when commonrange transmission control is used. Combining this result and previous work by Gupta and Kumar [8], we derive an expression for the average traffic carrying capacity of variablerangebased multihop networks. For 2, we show that this capacity remains constant even when more nodes are added to the network. Second, we derive a model that approximates the signaling overhead of a routing protocol as a function of the transmission range and node mobility for both route discovery and route maintenance. We show that there is an optimum setting for the transmission range, not necessarily the minimum, which maximizes the capacity available to nodes in the presence of node mobility. The results presented in this paper highlight the need to design future MAC and routing protocols for wireless ad hoc and sensor networks based, not on commonrange which is prevalent today, but on variablerange power control. Index Terms—Multihop networks, ad hoc networks, traffic capacity, network connectivity, power savings. Ç 1
Another Adaptive Distributed Shortest Path Algorithm
 IEEE Transactions on Communications
, 1991
"... We give a distributed algorithm to compute shortest paths in a network with changing topology. It does not suffer from the routing table looping behavior associated with the FordBellman distributed shortest path algorithm although it uses truly distributed processing. Its time and message complexiti ..."
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Cited by 42 (0 self)
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We give a distributed algorithm to compute shortest paths in a network with changing topology. It does not suffer from the routing table looping behavior associated with the FordBellman distributed shortest path algorithm although it uses truly distributed processing. Its time and message complexities are evaluated. Pierre Humblet is with the Laboratory for Information and Decision Systems, Massachusetts Institute of Technology, Cambridge MA 02139. This research was supported in part by Codex Corporation and in part by the Army Research Office under Grant No. DAAL0386K0171. 2 1) INTRODUCTION One of the oldest and best known problems in the field of distributed algorithms is to compute shortest paths between nodes in a network. This problem arises in the following context. We have a network of links and nodes (processors). Each link (I,J) is characterized by a direction dependent length LEN(I,J) that can change with time and can only be observed at node I. The nodes execute a distr...
Evolving fuzzy rule based controllers using genetic algorithms
 FUZZY SETS AND SYSTEMS
, 1996
"... The synthesis of geneticsbased machine learning and fuzzy logic is beginning to show promise as a potent tool in solving complex control problems in multivariate nonlinear systems. In this paper an overview of current research applying the genetic algorithm to fuzzy rule based control is presente ..."
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Cited by 39 (1 self)
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The synthesis of geneticsbased machine learning and fuzzy logic is beginning to show promise as a potent tool in solving complex control problems in multivariate nonlinear systems. In this paper an overview of current research applying the genetic algorithm to fuzzy rule based control is presented. A novel approach to geneticsbased machine learning of fuzzy controllers, called a Pittsburgh Fuzzy Classifier System # 1 (PFCS1) is proposed. PFCS1 is based on the Pittsburgh model of learning classifier systems and employs variable length rulesets and simultaneously evolves fuzzy set membership functions and relations. A new crossover operator which respects the functional linkage between fuzzy rules with overlapping input fuzzy set membership functions is introduced. Experimental results using PFCS1 are reported and compared with other published results. Application of PFCS1 to a distributed control problem (dynamic routing in computer networks) is also described and experimental results are presented.