waashk/acm huggingface dataset:
implementing remote procedure calls  remote procedure calls (rpc) are a useful paradigm for providing communication across a network between programs written in a high level language. this paper describes a package, written as part of the cedar project, providing a remote procedure call facility. the paper describes the options that face a designer of such a package, and the decisions we made. we describe the overall structure of our rpc mechanism, our facilities for binding rpc clients, the transport level communication protocol, and some performance measurements. we include descriptions of some optimisations we used to achieve high performance and to minimize the load on server machines that have many clients.  our primary aim in building an rpc package was to make the building of distributed systems easier. previous protocols were sufficiently hard to use that only members of a select group of communication experts were willing to undertake the construction of distributed systems. we hoped to overcome this by providing a communication paradigm as close as possible to the familiar facilities of our high level languages. to achieve this aim, we concentrated on making remote calls efficient, and on making the semantics of remote calls as close as possible to those of local calls.  andrew d. birrell bruce jay nelson
insights into the implementation and application of heterogeneous local area networks  the ideal local area network is a mechanism which provides concurrent high speed error-free data paths over a limited geographical area and between any computational entities on the network. a computational entity may be a program running on any type of computer, any intelligent device, or any terminal. this means that such an ideal network must be able to support systems of cooperating processes within disjoint and dissimilar host environments.  achieving such an ideal heterogeneous network (referred to as an "open" network with respect to the iso reference model for open systems interconnection) may be impossible in the limit. however, the ideal shows promise of being approachable. recent work in local area networks, protocols, and multiprocessor operating systems looks promising for attacking the problem.  this paper first discusses data paths and the dilemma of heterogeneous data communications. existing local area networks, their functionality, shortcomings, and relationship to networking standards are described. commercial lans are discussed and classified. standards, high level protocols, and operating system concepts are discussed and related to networks. finally some possible approaches to the implementation of hetergeneous networks are discussed.  william p. lidinsky
empirical study of latency hiding on a fine-grain parallel processor  latency associated with memory accesses and process communications are one of the most difficult obstacles in constructing a practical massively parallel system. so far, two approaches to hide latencies have been proposed. they are prefetching and multi- threading. an instruction-level data-driven computer is an ideal test-bed for evaluating these latency hiding methods because prefetching and multi-threading are naturally implemented in an instruction- level data- driven computer as unfolding and concurrent execution of multiple contexts. this paper evaluates latency hiding methods on sigma-1, a dataflow supercomputer developed in electrotechnical laboratory. as a result of evaluation, these methods are effective to hide static latencies but not effective to hide dynamic latencies. also, concurrent execution of multiple contexts is more effective than prefetching.  kei hiraki toshio shimada satoshi sekiguchi
a layered protocol architecture for multimedia wireless-pcs networks  coupled with the growing interest in the universal mobile telecommunication system (umts) as a standard for future mobile communications, the need for a set of functions to effectively support multimedia teleservices in such an environment is also increasing. starting from the idea that multimedia means the integrated manipulation of different information and hence the independent handling of separate information is not satisfactory, an enhanced protocol architecture for the support of multimedia teleservices in wireless personal communication systems based on umts is proposed. it involves physical, mac, data link, and network layers. a synchronisation sub-layer is introduced on the mac level with the main aim of assuring a rough multimedia inter-stream synchronisation over the air interface, which is a first step prior to a fine end-to-end synchronisation performed by higher layers. proposed functions, their basic algorithms, their location in the protocol stack, as well as the signalling exchange among modules implementing them, on network and user sides, are described in detail in the paper. the resulting architecture well fits the demanding nature of multimedia services and can be easily interfaced with the wired backbone of the system.  antonio iera salvatore marano antonella molinaro
paging strategy optimization in personal communication systems  mobility tracking is concerned with finding a mobile subscriber (ms) within the area serviced by the wireless network. the two basic operations for tracking an ms, location updating and paging, constitute additional load on the wireless network. the total cost of updating and paging can be minimized by optimally dividing the cellular area into location registration (lr) areas. in current systems broadcast paging messages are sent within the lr area to alert the ms of an incoming call. in this paper we propose a selective paging strategy which uses the ms mobility and call patterns to minimize the cost of locating an ms within an lr area subject to a constraint on the delay in locating the ms.  ahmed abutaleb victor o.k. li
performance of multiple-dwell pseudo-noise code acquisition with i-q detector on frequency-nonselective multipath fading channels  multiple-dwell pseudo-noise code acquisition with a noncoherent i-q detector is analyzed for rayleigh and rician fading channels that takes into account the detection correlations resulting from multipath fading. minimum mean acquisition times with optimized dwell times and thresholds are obtained, and the effects of multipath fading and frequency offsets are evaluated. in addition, a detailed comparison between i-q and square-law detectors is conducted under various channel conditions.  wern-ho sheen sauz chiou
dimensioning server access bandwidth and multicast routing in overlay networks  application-level multicast is a new mechanism for enabling multicast in the internet. driven by the fast growth of network audio/video streams, application-level multicast has become increasingly important for its efficiency of data delivery and its ability of providing value-added services to satisfy application specific requirements. from a network design perspective, application-level multicast differs drastically from traditional ip multicast in its network cost model and routing strategies. we present these differences and formulate them as a network design problem consisting of two parts: one is bandwidth assignment in the overlay network, the other is load-balancing multicast routing with delay constraints. we use analytical methods and simulations to show that our design solution is a valid and cost- effective approach. simulation results show that we are able to achieve network utilization within 10% of the best possible utilization while keeping the session rejection rate low.  sherlia y. shi jonathan s. turner marcel waldvogel
a distributed mechanism for power saving in ieee 802.11 wireless lans  the finite battery power of mobile computers represents one of the greatest limitations to the utility of portable computers. furthermore, portable computers often need to perform power consuming activities, such as transmitting and receiving data by means of a random-access, wireless channel. the amount of power consumed to transfer the data on the wireless channel os negatively affected by the channel congestion level, and significantly depends on the mac protocol adopted. this paper illustrates the design and the performance evaluation of a new mechanism that, by controlling the accesses to the shared transmission channel of a wireless lan, leads each station to an optimal power consumption level. specifically, we considered the standard ieee 802.11 distributed coordination function (dcf) access scheme for wlans. for this protocol we analytically derived the optimal average power consumption levels required for a frame transmission. by exploiting these analytical results, we define a power save, distributed contention control (ps-dcc) mechanism that can be adopted to enhance the performance of the standard ieee 802.11 dcf protocol from a power saving standpoint. the performance of an ieee 802.11 network enhanced with the ps-dcc mechanism has been investigated by simulation. results show that the enhanced protocol closely approximates the optimal power consumption level, and provides a channel utilization close to the theoretical upper bound for the ieee 802.11 protocol capacity. in addition, even in low load situations, the enhanced protocol does not introduce additional overheads with respect to the standard protocol.  luciano bononi marco conti lorenzo donatiello
the seventh generation  the fifth generation computer is fairly well defined. by extrapolation, we can make some statements about a sixth generation machine. but what of the seventh generation? this presentation explores one possible scenario for the seventh generation computer. general specifications, expandability factors, initial and operating costs, useful lifetime and special use-interactive characteristics will be defined.  the seventh generation system design will have to be sensitive to design constraints in the 2010 timeframe, including:  • energy availability,  • operational lifetime requirements,  • materials processing breakthroughs, and  • user requirements.  kerry mark joels
a partial-multiple-bus computer structure with improved cost effectiveness  this paper addresses the design and performance analysis of partial- multiple- bus interconnection networks. one such structure, called processor- oriented partial-multiple-bus (or ppmb), is proposed. it serves as an alternative to the conventional structure called memory-oriented partial- multiple-bus (or mpmb) and is aimed at higher system performance at less or equal system cost. ppmb's structural feature, which distinguishes itself from the conventional, is to provide every memory module with b paths to processors (where b is the total number of buses). this in contrast to the mere b/g paths provided in the conventional mpmb structure (where g is the number of groups), suggests a potential for higher system bandwidth. this potential is fully fulfilled by the load-balancing arbitration mechanism suggested, which in turn highlights the advantages of the proposed structure. as a result, it has been shown, both analytically and by simulation, that a substantial increase in system bandwidth (up to 20%) is achieved by the ppmb structure over the mpmb structure. in addition to the fact that the cost of ppmb is less than, or equal to, that of mpmb, its reliability is shown to be slightly increased as well.  h. jiang k. c. smith
a dynamic packet reservation multiple access scheme for wireless atm  the dynamic packet reservation multiple access (dprma) scheme, a medium access control protocol for wireless multimedia applications, is proposed and investigated. dprma allows the integration of multiple traffic types through a single access control mechanism that permits users to specify their immediate bandwidth requirements. the primary feature of dprma is the dynamic matching of the traffic source generation rates with the assigned portion of the channel capacity. this is accomplished by a control algorithm that regulates the actual amount of channel capacity assigned to users. to support multimedia communication, channel capacity assignments are prioritized by traffic type. the performance of the scheme is evaluated and the scheme is shown to perform well in a system with voice, video conferencing, and data users present. it is also shown to provide improved performance over a system with a modified version of the packet reservation multiple access (prma) scheme. furthermore, several system parameters are studied and optimized.  deborah a. dyson zygmunt j. haas
performance evaluation of multiple time scale tcp under self-similar traffic conditions  measurements of network traffic have shown that self- similarity is a ubiquitous phenomenon spanning across diverse network environments. in previous work, we have explored the feasibility of exploiting long-range correlation structure in self-similar traffic for congestion control. we have advanced the framework of multiple time scale congestion control and shown its effectiveness at enhancing performance for rate-based feedback control. in this article, we extend the multiple time scale control framework to window- based congestion control, in particular, tcp. this is performed by interfacing tcp with a large time scale module that adjusts the aggressiveness of bandwidth consumpton behavior exhibited by tcp as a function of large time scale network state, that is, information that exceeds the time horizon of the feedback loop as determined by rtt. how to effectively utilize such information---due to its probabilistic nature, dispersion over multiple time scales, and realization on top of existing window-based congestion controls--- is a nontrivial problem. first, we define a modular extension of tcp (a function call with a simple interface that applies to various flavors of tcp, e.g., tahoe, reno, and vegas) and show that it significantly improves performance. second, we show that multiple time scale tcp endows the underlying feedback control with proacativity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay- bandwidth product in broadband wide area networks. third, we investigate the influence of three traffic control dimensions---tracking ability, connection duration, and fairness---on performance. performance evaluation of multiple time scale tcp is facilitated by a simulation benchmark environment based on physical modeling of self-similar traffic. we explicate our methodology for disc  kihong park tsunyi tuan
integrated services packet networks with mobile hosts: architecture and performance  this paper considers the support of real-time services to mobile users in an integrated services packet network. in the currently existing architectures, the service guarantees provided to the mobile hosts are mobility dependent, i.e., mobile hosts experience wide variation in the quality of service and often service disruption when hosts move from one location to another. the network performance degrades significantly when mobile hosts are provided with mobility independent service guarantees. in this paper we have proposed a service model for mobile hosts that can support adaptive applications which can withstand service degradation and disruption, as well as applications which require mobility independent service guarantees. we describe an admission control scheme for implementing this service model and evaluate its performance by simulation experiments. simulation results show that, if sufficient degree of multiplexing of the mobility dependent and independent services are allowed, the network does not suffer any significant performance degradation and in particular our admission control scheme achieves high utilization of network resources.  anup kumar talukdar b. r. badrinath arup acharya
d-arm: a new proposal for multi-dimensional interconnection networks  this paper presents a new topology for multidimensional interconnection networks, namely d-arm, which has the goal of simultaneously providing a high network transmission capacity and a low information transfer delay. the new d-arm topology has a connection pattern arranged in alternated regular mesh fashions with toroidal boundaries. five distinct network attributes, normally used to characterize interconnection network topologies, were employed to analyze the d-arm topology: network diameter, bisection width, deflection index, degree of connectivity and symmetry. also the evaluation of the performance of the d-arm network through computer simulations was carried out based on the following measures: throughput and information transfer delay. an upper-bound of the network transmission capacity was derived in function of the network dimension (d) and length (w). in order to validate our proposal, as a viable topology among other well-known topologies, a comparative analysis among the d-arm, msn and shufflenet was performed. the analysis results show that the d-arm outperforms the msn and shufflenet in many aspects and suggest some plausible applications of the d-arm networks, e.g., broadband switching architecture, multiprocessor connection, high-speed man, wdm optical networks and photonic networks.  lee luan ling alberto jose centeno filho
scheduling in parallel systems with a hierarchical organization of tasks  to exploit multiple processors, a job is usually partitioned into several tasks that can be executed concurrently. these tasks wait for processors in task ready queue(s). there are two basic ways in which waiting ready tasks can be organized: centralized organization or distributed organization. in a centralized organization, a single central task queue is maintained. in the latter case, each processor has its own private ready queue of tasks. ideally, a central ready queue global to all processors is desired over the distributed organization. however, the centralized organization is not suitable for large parallel systems because the global task queue could become a bottleneck. a hierarchical organization has been proposed to incorporate the good features of these two organizations. this paper studies the impact of job and task scheduling policies on the performance of the hierarchical organization.  s. p. cheng s. dandamudi
design and control of micro-cellular networks with qos provisioning for data traffic  the major focus of this paper is the design and control of micro/picocellular wireless access systems supporting non-real-time (or data) traffic subject to a guaranteed quality-of-service as defined by four metrics: call blocking probability, cell overload probability, average wireless bandwidth available to a mobile terminal, and probability that the available wireless bandwidth per mobile is less than some specified threshold. we utilize a cell-cluster based call admission control concept and provide a model as well as an analytical methodology which can be used to design wireless micro-cellular networks (as specified by the number of base stations required to serve the traffic generated within a given geographical area), and to control new call admission such that once a call is admitted to the system, it will enjoy a predefined quality-of-service without requiring intervention of the network call processor independent of how large the erlang load offered to the network may become. this is an important property for wireless access networks: although the network may be traffic engineered to provide an acceptable call blocking probability under anticipated erlang load, user mobility may occasionally cause that load to exceed design thresholds, and yet the qos offered to already admitted calls must be maintained.  mahmoud naghshineh anthony s. acampora
computing performance as a function of the speed, quantity, and cost of the processors  everyone wants more computing power for their applications, and the industry has responded in two ways: first by increasing the speed of single cpu's, and second by deploying multiple processors in parallel. much controversy exists over how best to balance processor speed against the number of processors employed. is it better to have a single, very fast and very expensive cpu, thousands of very slow but very cheap cpu's, or is there some optimal mix in between? the value of single processors, measured in floating-point performance per dollar, is relatively easy to assess, but the corresponding value of parallel systems is obscured by the fact that applications are not generally perfectly parallel, with some loss in efficiency occurring due to sequential bottlenecks and communication overhead.  parallel speedup, the ratio of execution time on a single processor to that on p processors, is often used to capture the effect and measure the efficiency of parallel utilization. we argue that this measure of efficiency is not a good measure of parallel performance because it rewards slow processors. instead we evaluate delivered floating-point performance as a function of the number of processors for either constant aggregate performance of the processors, or constant total cost. from these measures we offer two conclusions:  1) for a given aggregate floating-point performance, actual delivered performance never increases with the number of processors.  and 2) for a given cost, delivered performance is maximized by selecting the fastest processor available at a given technology level, and employing as many as the budget allows.  these results, which are generally known to parallel researchers, are often overlooked in the marketing announcements promoting "massively parallel" systems. we motivate this discussion by giving measured performance results from an actual application, and then show the theoretical basis.  m. l. barton g. r. withers
the impact of a zero-scan internet checksumming mechanism this paper describes a "zero-scan" mechanism that reduces internet checksumming overhead from a per-byte scan (or copy) cost, to a small and constant per-message cost. unlike previous techniques, this mechanism requires no message buffering within the source. this will allow internet transport protocols to achieve transfer latencies comparable to specialized protocols implemented directly on high- speed lan (link-layer) services. in addition, this mechanism is transparent to systems outside of the source lan. hence, this mechanism affords applications the portability of internet protocols without sacrificing the high performance of specialized lan transport protocols.the proposed zero-scan checksumming scheme eliminates the last requirement for an additional data copy/scan, beyond the scan required to transmit or receive from the network channel. if this checksumming mechanism is combined with zero-copy operating system mechanisms that provide low-overhead transfer across application and kernel boundaries, a network interface architecture that provides separate message buffering is no longer required. a consequence is that the network interface may be reduced, essentially, to dma engines plus link- and physical-layer logic. taken one step further, the network interface could be integrated with the cpu to create an "internet microprocessor". these alternative interface designs are discussed, along with their requirements and effects upon operating system and computer system architectures. gregory g. finn steve hotz rod van meter