waashk/acm huggingface dataset:
tcp-peach: a new congestion control scheme for satellite ip networks  current tcp protocols have lower throughput performance in satellite networks mainly due to the effects of long propagation delays and high link error rates. in this paper, a new congestion control scheme called tcp-peach is introduced for satellite networks. tcp-peach is composed of two new algorithms, namely sudden start and rapid recovery, as well as the two traditional tcp algorithms, congestion avoidance and fast retransmit. the new algorithms are based on the novel concept of using dummy segments to probe the availability of network resources without carrying any new information to the sender. dummy segments are treated as low-priority segments and accordingly they do not effect the delivery of actual data traffic. simulation experiments show that tcp-peach outperforms other tcp schemes for satellite networks in terms of goodput. it also provides a fair share of network resources.  ian f. akyildiz giacomo morabito sergio palazzo
adaptive power management a hierarchical/distributed system  the automatic control of electrical system (aces) for aircraft shipboard applications was first demonstrated at the westinghouse aerospace electrical division in 1970 [4]. this system was implemented on a single computer which controlled the hardware directly with discrete signals. presently hierarchical and distributed computer architectures are being evaluated [3, 14], to perform the aces task. westinghouse is pursuing a combined hierarchical/distributed architecture for its adaptive power management (apm) system [5]. the hierarchical network performs system control, conflict resolution, and top level resource monitoring and adaption/reconfiguration. the distributed network performs the system input/output functions, all direct control and coordination of the peripherial hardware and the adaption/reconfiguration of their resource/control tables (see figure 10). in addition, apm complies with the air forces requirement to use the standard dais an/ayk-15a processor [10, 11]; the standard higher order programming language as defined in mil-std-1589 [12], and interface and data bus multiplex system standard mil-std-1553b [8, 9].  william f. honey
admission control with priorities: approaces for multi-rate wireless system  priority based link-bandwidth partitioning is required to support wireless multimedia services, having diverse qos (delay, throughput) requirements, in mobile ad hoc networks with multimedia nodes. a new class of service disciplines, termed "batch and prioritize" or bp admission control (ac), is proposed. the bp algorithms use the delay tolerance of applications to batch requests in time slots. bandwidth assignment is made either at the end of the slot, or during the slot, on a priority basis. analytical and simulation models are developed to quantify the performance of the bp schemes. the results are compared with those obtained for a first-come- first-served (fcfs) service discipline. the class of bp schemes trade off the delay and loss tolerance of applications to improve the net carried traffic on the link. further, such schemes enable an easy implementation for adaptive prioritization, where the degree of precedence given to an application varies with offered load and the link capacity.  deepak ayyagari anthony ephremides
log-based receiver-reliable multicast for distributed interactive simulation reliable multicast communication is important in large-scale distributed applications. for example, reliable multicast is used to transmit terrain and environmental updates in distributed simulations. to date, proposed protocols have not supported these applications' requirements, which include wide-area data distribution, low-latency packet loss detection and recovery, and minimal data and management over-head within fine-grained multicast groups, each containing a single data source.in this paper, we introduce the notion of _log-based receiver-reliable multicast_ (lbrm) communication, and we describe and evaluate a collection of log-based receiver reliable multicast optimizations that provide an efficient, scalable protocol for high- performance simulation applications. we argue that these techniques provide value to a broader range of applications and that the receiver-reliable model is an appropriate one for communication in general. hugh w. holbrook sandeep k. singhal david r. cheriton
a high performance broadcast file transfer protocol  this paper describes a broadcast bulk file transfer protocol and presents its performance characteristics. the protocol is for bulk file distribution over a single satellite channel. the transmitting site and multiple receiver sites share channel access time to send data and acknowledgements.  the protocol performance characteristics are investigated using a simulation model that includes modelling of the uplink and downlink error processes at both the transmitter and receivers. the results obtained show that this protocol offers efficient reliable bulk file transfer to multiple receivers using a single satellite channel.  j. s. j. daka a. j. waters
on the self-similar nature of ethernet traffic we demonstrate that ethernet local area network (lan) traffic is statistically _self- similar_, that none of the commonly used traffic models is able to capture this fractal behavior, and that such behavior has serious implications for the design, control, and analysis of high-speed, cell-based networks. intuitively, the critical characteristic of this self-similar traffic is that there is no natural length of a "burst": at every time scale ranging from a few milliseconds to minutes and hours, similar-looking traffic bursts are evident; we find that aggregating streams of such traffic typically intensifies the self-similarity ("burstiness") instead of smoothing it.our conclusions are supported by a rigorous statistical analysis of hundreds of millions of high quality ethernet traffic measurements collected between 1989 and 1992, coupled with a discussion of the underlying mathematical and statistical properties of self- similarity and their relationship with actual network behavior. we also consider some implications for congestion control in high-bandwidth networks and present traffic models based on self-similar stochastic processes that are simple, accurate, and realistic for aggregate traffic. will e. leland walter willinger murad s. taqqu daniel v. wilson
analysis of techniques to improve protocol processing latency this paper describes several techniques designed to improve protocol latency, and reports on their effectiveness when measured on a modern risc machine employing the dec alpha processor. we found that the memory system---which has long been known to dominate network throughput---is also a key factor in protocol latency. as a result, improving instruction cache effectiveness can greatly reduce protocol processing overheads. an important metric in this context is the _memory cycles per instructions_ (mcpi), which is the average number of cycles that an instruction stalls waiting for a memory access to complete. the techniques presented in this paper reduce the mcpi by a factor of 1.35 to 5.8. in analyzing the effectiveness of the techniques, we also present a detailed study of the protocol processing behavior of two protocol stacks---tcp/ip and rpc---on a modern risc processor. david mosberger larry l. peterson patrick g. bridges sean o'malley
the effect of channel-exit protocols on the performance of finite population radom-access systems  random-access systems (ras) for collision-type channels have been studied extensively under the assumption of an infinite population which generates a poisson arrival process. if the population is finite and if the (practically desirable) free-access channel-access protocol is used, then it is shown that the specification of a channel-exit protocol is crucial for the stability and the fairness of the ras. free-exit and blocked- exit protocols are analyzed and it is concluded that the p-persistent blocked- exit protocol provides the mechanisms to assure stability and fairness for a wide range of arrival process models.  peter mathys boi v. faltings
performance analysis of cellular mobile communication networks supporting multimedia services  this paper illustrates the development of an analytical model for a communication network providing integrated services to a population of mobile users, and presents performance results to both validate the analytical approach, and assess the quality of the services offered to the end users. the analytical model is based on continuous---time multidimensional birth--death processes, and is focused on just one of the cells in the network. the cellular system is assumed to provide three classes of service: the basic voice service, a data service with bit rate higher than the voice service, and a multimedia service with one voice and one data component. in order to improve the overall network performance, some channels can be reserved to handovers, and multimedia calls that cannot complete a handover are decoupled, by transferring to the target cell only the voice component and suspending the data connection until a sufficient number of channels become free. numerical results demonstrate the accuracy of the approximate model, as well as the effectiveness of the newly proposed multimedia call decoupling approach.  m. ajmone marsanr s. marano c. mastroianni m. meo
interference analysis in fixed service microwave links due to overlay of broadband ssds-cdma wireless local loop system  in this paper the results of the interference analysis in fs - ml due to new wll systems with broadband ssds - cdma techniques, sharing the same frequency band, is evaluated. effects of wll systems are expressed through the interference noise power at the fdm/fm receiver and ber at the dml receiver output, respectively. the results obtained show that in the typical working conditions with careful cell planning, interference can be neglected, and in most situations wll overlay would not cause excessive interference in the fs - ml. this conclusion is of great importance for the development of telecommunication systems, specially in rural areas, because it is possible to develop telecommunication systems fast and economically, without any additional frequency demands and under favourable economical conditions.  mirolav l. dukic marko b. babovic
mark iiifp hypercube concurrent processor architecture  the mark lllfp hypercube is a new generation of hypercube concurrent processor system developed at jpl/caltech, with peak performance of 5 mips, 14 mflops per node, and a peak communication rate of 6 mbytes per second. each node utilizes two motorola mc68020 microprocessors, an mc68882 scalar floating- point coprocessor, and a weitek 8000 floating-point chip set. one of the mc68020 processors serves as the application and computational processor, the other is dedicated to communication. the three processors are interconnected through a common system bus and share 4 mbytes of dynamic memory. each processor has his own fast local memory, which increases parallelism, minimizes shared memory referencing, reduces memory contentions and improves system performance.  j. tuazon j. peterson m. pniel
software fault isolation in wide area networks  the problem of real- time detection and isolation of errors in distributed software systems operating in a wide-area networked environment is considered. the approach presented combines the results of static software analysis with dynamic event- driven monitoring. static software analysis is used to generate a model of the distributed system. the model describes all possible executions of the processes composing the distributed system. the event-driven monitoring algorithm upon detecting an erroneous event uses the model to isolate the distributed software process states causing the fault. because this approach does not require the use of the network for fault isolation, it is ideal for use in the low-bandwidth, high-latency communications environments characterizing wide-area networks.  dinesh gambhir ivan frish micheal post
realizing fault resilience in web-server cluster  today, a successful internet service is absolutely critical to be up 100 percent of the time. server clustering is the most promising approach to meet this requirement. however, the existing web server-clustering solutions merely can provide high availability derived from their redundancy nature, but offer no guarantee about fault resilience for the service. in this paper, we address this problem by implementing an innovative mechanism which enables a web request to be smoothly migrated and recovered on another working node in the presence of server failure. we will show that request migration and recovery could be efficiently achieved in the manner of user transparency. the achieved capability of fault resilience is important and essential for a variety of critical services (e.g., e-commerce), which are increasingly widespread used. our approach takes an important step toward providing a highly reliable web service.  chu-sing yang mon-yen luo
graceful preemption for multi-link link layer protocols  this paper discusses a powerful priority mechanism that can be used on a physical communication medium supporting multiple, independent, logical data links. this scheme allows a high priority message to immediately interrupt a lower priority message which is in the process of being transmitted, and yet will not require the retransmission of the first part of the lower priority message; hence, the term graceful preemption. graceful preemption may be extended to furnish multiple priority levels similar to existing processor interrupt structures which implement multiple levels. this protocol may serve a single processor which handles several different processes, or several independent stations that share a common bus. hence, priority levels can be enforced without the need for a centralized bus "master" or "arbitrator" unit. as an example, the application of graceful preemption to the integrated services digital network (isdn) link access procedure, lapd, is discussed.  m. wm. beckner t. j. j. starr
noncoherent multistage multiuser detection of m-ary orthogonal signals  in recent years, a great deal of research has been performed on methods of alleviating the performance degradations suffered by code division multiple access (cdma) systems due to multiple access interference. in this paper, we consider a multistage detector for noncoherent cdma using m-ary orthogonal signals. using a decorrelating detector as its first stage, the detector iteratively estimates the multiple access interference affecting the desired signal, subtracts the estimated interference, and forms symbol estimates for each of k users. through numerical examples, the bit error performance of the proposed detector is demonstrated to be superior to that of previous detectors for the same signalling scheme.  christopher j. hegarty branimir r. vojcic
protocol validation in complex systems  protocol validation and verification techniques have been applied successfully for a number of years to a wide range of protocols. the increasing complexity of our communications systems requires us to examine existing techniques and make a realistic assessment of which techniques will be applicable to the complex systems of the future. we believe that validation techniques based on an exhaustive reachability analysis will not be effective. sampling techniques, such as executing a random walk through the reachable state space, are effective in complex systems, since most protocol errors occur in many different states of the system.  more than 10 years have elapsed since the first automated validation techniques were first applied to communications protocols [1,2]. in the meantime, considerable advances have been made in validation technology, but more significantly, the scale and nature of the validation problem have changed. the communications systems that we need to validate today are significantly more complex than those of ten years ago. our methods must evolve in order to address the current challenge.  this paper is concerned primarily with the nature of the validation process, and the results that we might reasonably expect to achieve when validating protocols in complex communications systems.  c. h. west
a yellow-pages service for a local-area network  we introduce a yellow-pages service that maps service names into server addresses. the service is novel in that it associates a set of attributes with each server. clients specify the attributes the server should possess when requesting a service and the yellow-pages service determines what servers satisfy the request. in addition to describing the implementation of the yellow-pages service within a local-area network, we show how the service can be integrated with the available internet communication protocols to enable clients from throughout the internet to access local servers.  l. l. peterson
hll architectures: pitfalls and predilections  an examination of high- level language architectures reveals that some design considerations are based on inaccurate premises. this paper discusses some hll architecture design misconceptions. some features that should be considered in the design of hll architectures are presented. based on the hll architecture design considerations, a methodology for quantifying architecture is proposed.  krishna kavi boumediene belkhouche evelyn bullard lois delcambre stephen nemecek
indulgent algorithms (preliminary version)  informally, an indulgent algorithm is a distributed algorithm that tolerates unreliable failure detection: the algorithm is indulgent towards its failure detector. this paper formally characterises such algorithms and states some of their interesting features. we show that indulgent algorithms are inherently safe and uniform. we also state impossibility results for indulgent solutions to divergent problems like consensus, and failure-sensitive problems like non- blocking atomic commit and terminating reliable broadcast.  rachid guerraoui
the distributed v kernel and its performance for diskless workstations  the distributed v kernel is a message-oriented kernel that provides uniform local and network interprocess communication. it is primarily being used in an environment of diskless workstations connected by a high-speed local network to a set of file servers. we describe a performance evaluation of the kernel, with particular emphasis on the cost of network file access. our results show that over a local network:  1\\. diskless workstations can access remote files with minimal performance penalty.  2\\. the v message facility can be used to access remote files at comparable cost to any well-tuned specialized file access protocol.  we conclude that it is feasible to build a distributed system with all network communication using the v message facility even when most of the network nodes have no secondary storage.  david r. cheriton willy zwaenepoel
alpha transport  the control of the resources of a packet switching network is a very difficult problem to solve.1 past attempts to solve this problem have been handicapped primarily by lack of an adequate means to quantify the user demands and then assign distributed resources to the demands in a globally coherent way.  this paper presents a new approach to control the resources of packet switching networks. the key to this control is a new network transport scheme called alpha transport. alpha transport combines the tdm circuit switching concept and packet switching technology. it is easy to implement and particularly cost effective to carry the subnet traffic of meshed packet switching networks. alpha transport is robust, enables high utilization of the subnet bandwidth, reduces the subnet delay, and provides fairness.  bahram enshayan
a two-symbols/branch mbcm scheme based on 8-psk constellation under fading channels  a two-symbols/branch scheme of multiple block coded modulation (mbcm) is investigated under fading channels. compared with a conventional scheme of block coded modulation (bcm), this two-symbols/branch mbcm scheme greatly increases the minimum squared euclidean distance (msed), minimum symbol distance (msd), and minimum product distance (mpd). these three distances determine the bit-error-rate (ber) performance under either gaussian or fading channels. a pilot symbol assisted fading compensation, as well as the techniques of symbol interleaving and branch weighting, are employed to combat the effect of channel fading. through computer simulations, it is shown that large coding gains are obtained under both rayleigh and rician fading channels.  huan-bang li tetsushi ikegami
toward a dataflow/von neumann hybrid architecture  dataflow architectures offer the ability to trade program level parallelism in order to overcome machine level latency. dataflow further offers a uniform synchronization paradigm, representing one end of a spectrum wherein the unit of scheduling is a single instruction. at the opposite extreme are the von neumann architectures which schedule on a task, or process, basis.  this paper examines the spectrum by proposing a new architecture which is a hybrid of dataflow and von neumann organizations. the analysis attempts to discover those features of the dataflow architecture, lacking in a von neumann machine, which are essential for tolerating latency and synchronization costs. these features are captured in the concept of a parallel machine language which can be grafted on top of an otherwise traditional von neumann base. in such an architecture, the units of scheduling, called scheduling quanta, are bound at compile time rather than at instruction set design time. the parallel machine language supports this notion via a large synchronization name space.  a prototypical architecture is described, and results of simulation studies are presented. a comparison is made between the mit tagged-token dataflow machine and the subject machine which presents a model for understanding the cost of synchronization in a parallel environment.  r. a. iannucci
gip: an infrastructure for mobile intranets development the gprs and umts specifications define the procedures supportingthe mobility and the data sessions of a mobile user moving withinthe area of the corresponding plmns. for the case, though, ofmobile users working in group, using a plmn infrastructure, theaforementioned networks foresee no special treatment. however,services tightly related to a specific geographic area, like forexample security or surveillance services, could be implemented bya group of collaborating mobile nodes forming a mobile intranetthat uses the facilities of a plmn. in this paper, after adescription of what the specifications provide, methods areproposed for the deployment of intranets over the gprs or the umtsinfrastructure. at this aim, the concept of the gip is introducedregarding a frame of interconnected sgsns, within the gprs/umtsenvironment. this frame supports, without the intervention of theggsn, the mobility of a number of mobile nodes belonging to thesame group, as well as the data traffic between them. moreover, theadditional tasks to be undertaken by the sgsns forming the frameare described. constantinos f. grecas sotirios i. maniatis iakovos s. venieris
throughput-delay characteristics and stability considerations of the access channel in a mobile telephone system  in this paper a performance study of the access channel in a cellular mobile telephone system /1/ is presented. the method used in the cellular system for multiplexing the population of mobile terminals over the access channel is a hybrid between the methods known as csma/cd and btma. in the paper we extend an analysis of csma/cd to accomodate the function of the particular random multiaccess protocol. results are shown which illustrate the equilibrium channel performance and the approximate stability-througput-delay tradeoff. finally an estimate of the average message delay is given.  bengt stavenow