waashk/acm huggingface dataset:
rate-based congestion control for atm networks  congestion control plays an important role in the effective and stable operation of atm networks. this paper first gives a historical overview of rate-based congestion control algorithms developed in the atm forum, showing how the current atm forum standard regarding the traffic management control methods is exploited, by these algorithm. then, analytical approach is used to quantitatively evaluate their performance and show the effectiveness of the rate-based approach. in presenting the numerical examples, we emphasize that appropriate control parameter settings are essential for proper traffic management in an atm network environment.  hiroyuki ohsaki masayuki murata hiroshi suzuki chinatsu ikeda hideo miyahara
protocols for large data transfers over local networks  in this paper we analyze protocols for transmitting large amounts of data over a local area network. the data transfers analyzed in this paper are different from most other forms of large-scale data transfer protocols for three reasons: (1) the definition of the protocol requires the recipient to have sufficient buffers available to receive the data before the transfer takes place; (2) we assume that the source and the destination machine are more or less matched in speed; (3) the protocol is implemented at the network interrupt level and therefore not slowed down by process scheduling delays.  we consider three classes of protocols: stop-and-wait, sliding window and blast protocols. we show that the expected time of blast and sliding window protocols is significantly lower than the expected time for the stop-and-wait protocol, with blast outperforming sliding window by some small amount. although the network error rate is sufficiently low for blast with full retransmission on error to be acceptable, the frequency of errors in the network interfaces makes it desirable to use a more sophisticated retransmission protocol. a go- back-n strategy is shown to be only marginally inferior to selective retransmission and is, given its simplicity, the retransmission strategy of choice.  our results are based on measurements collected on sun workstations connected to a 10 megabit ethernet network using 3-com interfaces. the derivation of the elapsed time in terms of the network packet error rate is based on the assumption of statistically independent errors.  willy zwaenepoel
reaching agreement in the presence of faults  the problem addressed here concerns a set of isolated processors, some unknown subset of which may be faulty, that communicate only by means of two-party messages. each nonfaulty processor has a private value of information that must be communicated to each other nonfaulty processor. nonfaulty processors always communicate honestly, whereas faulty processors may lie. the problem is to devise an algorithm in which processors communicate their own values and relay values received from others that allows each nonfaulty processor to infer a value for each other processor. the value inferred for a nonfaulty processor must be that processor's private value, and the value inferred for a faulty one must be consistent with the corresponding value inferred by each other nonfaulty processor.  it is shown that the problem is solvable for, and only for, n ≥ 3m \\+ 1, where m is the number of faulty processors and n is the total number. it is also shown that if faulty processors can refuse to pass on information but cannot falsely relay information, the problem is solvable for arbitrary n ≥ m ≥ 0\. this weaker assumption can be approximated in practice using cryptographic methods.  m. pease r. shostak l. lamport
automatic update of replicated topology data bases  in computer communication networks, routing is often accomplished by maintaining copies of the network topology and dynamic performance characteristics in various network nodes. the present paper describes an algorithm that allows complete flexibility in the placement of the topology information. in particular, we assume that an arbitrary subset of network nodes are capable of maintaining the topology. in this environment, protocols are defined to allow automatic updates to flow between these more capable nodes. in addition, protocols are defined to allow less capable nodes to report their topology data to the major nodes, and acquire route information from them.  jeffrey m. jaffe adrian segall
editorial  the authors conclude that it was fairly easy to make applications use odyssey ---even for applications for which the source code was not available. independent adaptive applications do not need to be aware to each other. wavevideo---an integrated approach to adaptive wireless video", by george fankhauser, marcel dasen, nathalie weiler, bernhard plattner, and bukhard stiller, presents an integrated adaptive video coding architecture for heterogeneous wireless networks, based on joint source/channel coding. wavevideo adapts to dynamic channel conditions in two ways: the coding has mechanisms to overcome transmission errors, and the amount of error-control information is controlled by end-to-end feedback from the receiver. additionally, wavevideo can scale the reception quality of multiple heterogeneous receivers that receive a multicast video stream. the authors conclude that the wavevideo video coding architecture can effectively adapt to that dynamics to heterogenous wireless networks. "a trace- based evaluation of adaptive error correction for a wireless local area network", by david eckhardt and peter steenkiste, evaluates error control strategies for a wireless lan, and concludes that an adaptive forward error control algorithm which varies both the packet size and the degree of redundancy depending on the channel conditions is able to effectively adapt to the dynamics of a wireless lan environment. "an evaluation of quality of service characteristics of pacs packet channel", by behcet sarikaya and mehmet ulema, studies the quality of service characteristics, integration with the internet, and handover characteristics of one of the pcs standards---the personal access communication systems (pacs) packet channel---with a view of supporting multimedia communication in this environment.  vaduvur bharghavan c.-k. toh
fifth workshop on computer architecture for non-numeric processing: a flexible image processor using array elements  the purpose of this short paper is to describe some activities in our laboratory on designing a flexible image processor using array processing elements. in many document creation applications, it is desirable to include image handling capability in the system together with keystroke captured text processing function. however, this image handling creates two problems: one is the large amount of data needed for image storage, and the other is the large amount of processing required to produce an output image. data compression reduces storage and transmission bandwidth requirements, but it also requires processing power to do compression and de-compression of images. the objective of the study is to provide low-cost hardware which has the flexibility to do a variety of image processing algorithms.  ronnie k. l. poon kwan y. wong
the agree predictor: a mechanism for reducing negative branch history interference deeply pipelined, superscalar processors require accurate branch prediction to achieve high performance. two-level branch predictors have been shown to achieve high prediction accuracy. it has also been shown that branch interference is a major contributor to the number of branches mispredicted by two-level predictors.this paper presents a new method to reduce the interference problem called agree prediction, which reduces the chance that two branches aliasing the same pht entry will interfere negatively. we evaluate the performance of this scheme using full traces (both user and supervisor) of the specint95 benchmarks. the result is a reduction in the misprediction rate of gcc ranging from 8.62% with a 64k-entry pht up to 33.3% with a 1k-entry pht. eric sprangle robert s. chappell mitch alsup yale n. patt
handover in a micro-cell packet switched mobile network  this paper proposes a distributed handover protocol for a micro-cell packet switched mobile network. in such a network, users move from one cell to another very often, and each change of location may result in misrouted and lost packets. the purpose of the new protocol is to minimize these consequences of location changes: as long as a mobile moves from one cell to another but stays in the same region, the protocol avoids loss of packets and preserves order of transmission. thus it increases the performance of the transport layer protocol by minimizing the need to retransmit packets.  reuven cohen baiju v. patel adrian segall
resource allocation and management in diffserv networks for ip telephony  this paper discusses resource allocation and management in differentia ted services (diffserv) networks, particularly in the context of ip telephony. we assume that each node uses weighted fair queuing (wfq) schedulers in order to provide quality of service (qos) to aggregates of traffic. all voice traffic destined for a certain output interface is aggregated into a single queue. when a voice flow traverses a node, its packets are placed in this queue; which is drained at a certain rate, determined by a weight associated with that queue. this paper shows how to set this weight such that the edge-router- to-edge-router queuing delay in the diffserv network is statistically bounded. the nodes are modeled as m/g/1 queuing systems and a heuristic formula is used to compute a quantile of the queuing delay. this formula is compared with results derived from simulations. it is also shown how to use this result to allocate the appropriate resources in a diffserv network and how to update and process rsvp messages at the edge of a diffserv network in an intserv over diffserv scenario.  maarten buchli danny de vleeschauwer jan janssen annelies van moffaert guido h. petit
remote pipes and procedures for efficient distributed communication  we describe a new communication model for distributed systems that combines the advantages of remote procedure call with the efficient transfer of bulk data. three ideas form the basis of this model. first, remote procedures are first-class values which can be freely exchanged among nodes, thus enabling a greater variety of protocols to be directly implemented in a remote procedure call framework. second, a new type of abstract object, called a pipe, allows bulk data and incremental results to be efficiently transported in a type-safe manner. unlike procedure calls, pipe calls do not return values and do not block a caller. data sent down a pipe is received by the pipe's sink node in the order sent. third, the relative sequencing of pipes and procedures can be controlled by combining them into channel groups. calls on the members of a channel group are guaranteed to be processed in order. application experience with this model, which we call the channel model, is reported. derived performance bounds and experimental measures demonstrate k pipe calls can perform min( 1 + (r/p), k) times faster than k procedure calls, where r is the total roundtrip remote communication time and p is the procedure execution time.  david k. gifford nathan glasser
using microcomputers as satellites in a time-sharing environment  so it goes, these days, in colleges across the land. the comments about 8's and 89's are from ph.d. mathematicians, not discussing number theory, but debating microcomputers. (the fellow in the back obviously had not kept up with the newest new math.) even the ivory tower mathematicians are being drawn into the microcomputer revolution.  until a few years ago, mathematics and science at st. olaf college, as at most colleges, used a central time-sharing minicomputer for all instructional needs. the twin dartmouth inventions of basic and time-sharing seemed ideal tools for computing in an undergraduate environment.  lynn arthur steen j. arthur seebach
atm concepts, architectures, and protocols  asynchronous transfer mode (atm) is often described as the future computer networking paradigm that will bring high-speed communications to the desktop. what is atm? how is it different from today's networking technologies? this article is intended to acquaint readers with this emerging technology and describe some of the concepts embodied within it. in order to understand why atm was created and how it works, we first need to review a bit of computer networking history.  ronald j. vetter
virtual topology based routing protocol for multihop dynamic wireless networks in this paper, a new hierarchical multihop routing algorithm and its performance evaluation is presented for fully dynamic wireless networks. the routing algorithm operates on a virtual topology obtained by partitioning the routing information for mobile terminals and mobile base stations into a hierarchical, distributed database. based on the virtual topology, each mobile base station stores a fraction of the routing information to balance the complexity of the location-update and the path-finding operations. mobility of the network entities changes the load distribution and causes processing and memory bottlenecks in some parts of the network. however, since the network routing elements are also mobile, their movement can be used to distribute the load. thus, new load balancing schemes are introduced to distribute the routing overhead uniformly among the mobile base stations. the performance of the hierarchical multihop routing algorithm is investigated through simulations. it is shown that the routing protocol can cope with high mobility and deliver packets to the destinations successfully. ian f. akyildiz james i. pelech bulent yener
optimal pipelining in supercomputers  this paper examines the relationship between the degree of central processor pipelining and performance. this relationship is studied in the context of modern supercomputers. limitations due to instruction dependencies are studied via simulations of the cray-1s. both scalar and vector code are studied. this study shows that instruction dependencies severely limit performance for scalar code as well as overall performance.  the effects of latch overhead are then considered. the primary cause of latch overhead is the difference between maximum and minimum gate propagation delays. this causes both the skewing of data as it passes along the data path, and unintentional clock skewing due to clock fanout logic. latch overhead is studied analytically in order to lower bound the clock period that may be used in a pipelined system. this analysis also touches on other points related to latch clocking. this analysis shows that for short pipeline segments both the earle latch and polarity hold latch give the same clock period bound for both single-phase and multi-phase clocks. overhead due to data skew and unintentional clock skew are each added to the cray-1s simulation model. simulation results with realistic assumptions show that eight to ten gate levels per pipeline segment lead to optimal overall performance. the results also show that for short pipeline segments data skew and clock skew contribute about equally to the degradation in performance.  s. r. kunkel j. e. smith
x.400-based distributed application design methodology  the objective of this paper is to provide a distributed application design methodology using the x.400 standards. this one can be applied to two distributed application models: the client/server model and the peer to peer model. the client/server model relies on a relationship between a server entity and a client entity. the use of x.400 for this model is based on the defined relationship between the ua and the ms. the peer to peer model consists of a set of cooperating entities offering a service to the users. the use of x.400 for this model requires the creation of new mts users and of a p2 type protocol enabling them to communicate. we analyze the advantages and disadvantages of each proposed alternative.  laurence duchien valerie gay eric horlait
the architecture and programming of the ametek series 2010 multicomputer  during the period following the completion of the cosmic cube experiment [1], and while commercial descendants of this first-generation multicomputer (message-passing concurrent computer) were spreading through a community that includes many of the attendees of this conference, members of our research group were developing a set of ideas about the physical design and programming for the second generation of medium-grain multicomputers.  our principal goal was to improve by as much as two orders of magnitude the relationship between message-passing and computing performance, and also to make the topology of the message-passing network practically invisible. decreasing the communication latency relative to instruction execution times extends the application span of multicomputers from easily partitioned and distributed problems (eg, matrix computations, pde solvers, finite element analysis, finite difference methods, distant or local field many-body problems, ffts, ray tracing, distributed simulation of systems composed of loosely coupled physical processes) to computing problems characterized by "high flux" [2] or relatively fine-grain concurrent formulations [3, 4] (eg, searching, sorting, concurrent data structures, graph problems, signal processing, image processing, and distributed simulation of systems composed of many tightly coupled physical processes). such applications place heavy demands on the message-passing network for high bandwidth, low latency, and non-local communication. decreased message latency also improves the efficiency of the class of applications that have been developed on first- generation systems, and the insensitivity of message latency to process placement simplifies the concurrent formulation of application programs.  our other goals included a streamlined and easily layered set of message primitives, a node operating system based on a reactive programming model, open interfaces for accelerators and peripheral devices, and node performance improvements that could be achieved economically by using the same technology employed in contemporary workstation computers.  by the autumn of 1986, these ideas had become sufficiently developed, molded together, and tested through simulation to be regarded as a complete architectural design. we were fortunate that the ametek computer research division was ready and willing to work with us to develop this system as a commercial product. the ametek series 2010 multicomputer is the result of this joint effort.  c. l. seitz w. c. athas c. m. flaig a. j. martin j. seizovic c. s. steele w-k. su
the operating system and language support features of the bellmactm-32 microprocessor.  the bellmac-32 microprocessor is a 32-bit microprocessor, implemented with cmos technology, designed to support operating system functions and high level languages efficiently. the architecture was designed with the following objectives in mind:  • high performance.  • enhanced operating system support capabilities.  • high level language support.  • high reliability, availability and maintainability.  alan d. berenbaum michael w. condry priscilla m. lu
proposed nist standard for role-based access control in this article we propose a standard for role-based access control (rbac). although rbac models have received broad support as a generalized approach to access control, and are well recognized for their many advantages in performing large-scale authorization management, no single authoritative definition of rbac exists today. this lack of a widely accepted model results in uncertainty and confusion about rbac's utility and meaning. the standard proposed here seeks to resolve this situation by unifying ideas from a base of frequently referenced rbac models, commercial products, and research prototypes. it is intended to serve as a foundation for product development, evaluation, and procurement specification. although rbac continues to evolve as users, researchers, and vendors gain experience with its application, we feel the features and components proposed in this standard represent a fundamental and stable set of mechanisms that may be enhanced by developers in further meeting the needs of their customers. as such, this document does not attempt to standardize rbac features beyond those that have achieved acceptance in the commercial marketplace and research community, but instead focuses on defining a fundamental and stable set of rbac components. this standard is organized into the rbac reference model and the rbac system and administrative functional specification. the reference model defines the scope of features that comprise the standard and provides a consistent vocabulary in support of the specification. the rbac system and administrative functional specification defines functional requirements for administrative operations and queries for the creation, maintenance, and review of rbac sets and relations, as well as for specifying system level functionality in support of session attribute management and an access control decision process. david f. ferraiolo ravi sandhu serban gavrila d. richard kuhn ramaswamy chandramouli
the vmp network adapter board (nab): high-performance network communication for multiprocessors  high performance computer communication between multiprocessor nodes requires significant improvements over conventional host- to-network adapters. current host-to-network adapter interfaces impose excessive processing, system bus and interrupt overhead on a multiprocessor host. current network adapters are either limited in function, wasting key host resources such as the system bus and the processors, or else intelligent but too slow, because of complex transport protocols and because of an inadequate internal memory architecture. conventional transport protocols are too complex for hardware implementation and too slow without it.  in this paper, we describe the design of a network adapter board for the vmp multiprocessor machine that addresses these issues. the adapter uses a host interface that is designed for minimal latency, minimal interrupt processing overhead and minimal system bus and memory access overhead. the network adapter itself has a novel internal memory and processing architecture that implements some of the key performance-critical transport layer functions in hardware. this design is integrated with vmtp, a new transport protocol specifically designed for efficient implementation on an intelligent high- performance network adapter. although targeted for the vmp system, the design is applicable to other multiprocessors as well as uni- processors.  h. kanakia d. cheriton
performance and fault tolerance improvements in the inverse augmented data manipulator network  the inverse augmented data manipulator (iadm) is a multistage interconnection network based on the augmented data manipulator (adm) and feng's data manipulator. it is designed to be used in large-scale parallel/distributed processing systems for communication among processors, memories, and other system devices. two aspects of iadm network design are discussed: performance and fault tolerance. a single stage look-ahead scheme for predicting blockage is presented to enhance performance. next, one method of adding some links to the network to enable it to tolerate one link failure is described. finally, a different method of adding links is shown that both improves performance and allows the network to tolerate two switching element or two link failures. included is a new routing tag scheme that accommodates the new links.  robert j. mcmillen howard jay siegel