A. Pnueli. The Temporal Logic of Programs. Proc. of the 18th IEEE Symposium on Foundations of Computer Science, pp.46-57, IEEE Computer Society Press, 1977.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....about the system. Wewillgive an example of such a property later in this paper. In its most general form, Spin supports the automated ver ification of properties stated in linear temporal logic, a standard method for specifying properties of concurrent systems introduced in the late seventies [7]. 4 An Example For an application of these ideas, we studied Lucent s Actiview Provisioning offering for Wireless operators. Actiview is a workflow management product sold in a number of markets, suchas Commercial local exchange carriers, Wireless service providers, Domestic local operating ....

A. Pnueli, 'The temporal logic of programs,' Proc. 18th IEEE Symposium on Foundations of Computer Science, 1977, pp. 46-77.

....es the analysis greatly, and appears to be an interesting tool for hierarchical network design problems. Our techniques build upon the results of Guha et al. [9] for the Access Network Design problem, a special case of single sink buy at bulk. This problem was rst de ned by Andrews and Zhang [1], in which a feasible solution must utilize all cables to a minimum fractional capacity. They observed that the solution for the Access Network Design problem appears to be a recursive collection of shortest path trees. However, for the problem discussed herein, we show that the solution (upto ....

....this work, Garg et al. [8] obtained a O(K) approximation (where K is the number of di erent cable types) to the single sink buy at bulk problem by rounding the natural LP formulation. The Access Network Design problem, a special case of single sink buy at bulk, was introduced by Andrews and Zhang [1] and the rst constant approximation was given by Guha et al. [9] Meyerson et al. provided an O(log n) approximation in [12] for the more general problem where cable types may have limited availability. Organization of the Paper In Section 2, we state the single sink buy at bulk problem ....

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M. Andrews and L. Zhang. The access network design problem. 39th IEEE Symposium on Foundations of Computer Science, pages 40-49, 1998.

....the future we will have to prove the security of practical schemes for much weaker assumptions. For several public key schemes it was proved that computing certain bits of the secret (the plaintext or the shared key in case of the Diffie Hellman protocol) is as hard as computing the entire value [3, 13, 39]. 8 Cryptographic Protocols Cryptographic protocols, often based on public key functionality, are among the most delicate and fascinating topics in cryptography. In the past decade there has been an extensive research activity on various types of protocols, in particular on interactive proofs ....

J. Hastad and M. Naslund, The security of individual RSA bits, Proc. 39th IEEE Symposium on the Foundations of Computer Science (FOCS), pp. 510--519, IEEE Press, 1998.

....algorithm also improves the best known approximation ratio and running time for the offline version of this problem. 1 Introduction The problem of designing networks using trunks to route demands has received considerable attention. In this problem, commonly known as Buy at Bulk Network Design [14, 3, 2, 13], we are given demands at nodes in a network which have to be routed to their respective destinations using pipes of certain capacities and costs per unit length. The costs obey economies of scale, in the sense that it is cheaper to buy a pipe of larger capacity than many pipes (which sum to the ....

....and costs per unit length. The costs obey economies of scale, in the sense that it is cheaper to buy a pipe of larger capacity than many pipes (which sum to the same capacity) of a smaller capacity. The goal is to optimize the total cost of the pipes we buy to route the demands. Andrews and Zhang [2] define a special case Department of Computer Science, Stanford University CA 94305. Supported by ARO DAAG 55 97 1 0221. Email: awm cs.stanford.edu. y Department of Computer Science, Stanford University CA 94305. Supported by ONR N00014 98 1 0589. Email: kamesh cs.stanford.edu. z Supported ....

[Article contains additional citation context not shown here]

M. Andrews and L. Zhang. The access network design problem. 39th IEEE Symposium on Foundations of Computer Science, pages 40--49, 1998.

....of properties. We have not yet discussed how these properties can be expressed in such a way that automated analysis becomes possible. Propositional linear temporal logic (LTL) allows us to make very concise statements about required causal relations between the events in a distributed system [P77], E90] Each LTL formulae, furthermore, can be converted mechanically [GPVW95] into an w automaton [T90] that can be used in the verification process. An automata theoretic verification method [VW86] proceeds follows. 1. The property to be verified is expressed as a formula f in LTL, and then ....

....formalism for expressing logical requirements on a distributed system and automata representations. That link is provided by propositional linear temporal logic. Linear temporal logic (LTL) was proposed in the late seventies by Amir Pnueli as a formalism for reasoning about concurrent systems [P77]. The main notions used in the definition of temporal logic were derived from earlier work on Tense Logics for tightening arguments relating to the passage of time. Curiously, this work did not originate in computer science but in philosophy [P57] P67] RU71] Propositional linear temporal logic ....

A. Pnueli, The temporal logic of programs. Proc. 18th IEEE Symposium on Foundations of Computer Science, 1977, Providence, R.I., pp. 46-57.

....the analysis greatly, and appears to be an interesting tool for hierarchical network design problems. Our techniques build upon the results of Guha et al. [8] for the Access Network Design problem, a special case of single sink buy at bulk. This problem was first defined by Andrews and Zhang [1], in which a feasible solution must utilize all cables to a minimum fractional capacity. They observed that the solution for the Access Network Design problem appears to be a recursive collection of shortest path trees. However, for our problem, we show that the solution alternates between ....

.... may be improved to O(log n log log n) using subsequent results of Bartal [5] on probabilistic approximation of metrics using trees, and may be derandomized using the results of [6, 7] The Access Network Design problem, a special case of single sink buy at bulk, was introduced by Andrews and Zhang [1] and the first constant approximation was given by Guha et al. [8] Meyerson et al. provided an O(log n) approximation in [11] for the more general problem where cable types may have limited availability. Organization of the Paper In Section 2, we state the single sink buy at bulk problem ....

[Article contains additional citation context not shown here]

M. Andrews and L. Zhang. The access network design problem. 39th IEEE Symposium on Foundations of Computer Science, pages 40--49, 1998.

....from one layer to the next. We provide the first constant factor combinatorial approximation for this problem. Access Network Design The problem of designing networks using trunks to route demands has received considerable attention. In this problem, commonly known as Buyat Bulk Network Design [22, 5, 4, 20], we are given demands at nodes in a network which have to be routed to their respective destinations using pipes of certain capacities and costs per unit length. The costs obey economies of scale, in the sense that it is cheaper to buy a pipe of larger capacity than many pipes (which sum to the ....

....and costs per unit length. The costs obey economies of scale, in the sense that it is cheaper to buy a pipe of larger capacity than many pipes (which sum to the same capacity) of a smaller capacity. The goal is to optimize the total cost of the pipes we buy to route the demands. Andrews and Zhang [4] define a special case of this problem called the Access Network Design problem, where all demands need to be routed to a central core network and the costs and capacities of the pipes obey certain common constraints. They show applications of this problem in designing telephone networks. Load ....

[Article contains additional citation context not shown here]

M. Andrews and L. Zhang. The access network design problem. 39th IEEE Symposium on Foundations of Computer Science, pages 40--49, 1998.

....that traffic. If all functions are convex increasing (nondecreasing derivative) then exact solutions are known using min cost flow techniques. We present the first approximations for the case where all functions are concave increasing (nonincreasing derivative) Previous work on buy at bulk [5, 4, 27] required that the concave functions between each pair of nodes be identical up to a constant scaling factor; we eliminate this requirement. In addition to generalizing previous results, our algorithm is easy to implement and has a small running time. This makes it the algorithm of choice for ....

....This makes it the algorithm of choice for many of the problems we have previously described. For example, previous algorithms for single source buy at bulk depended on complicated methods of randomly selecting trees which approximate stretch [7, 8, 10, 11] The algorithm for Access Network Design [4] depended on linear programming relaxation. Our algorithm s most time consuming subroutine is single pair shortest path. Summary of Previous Results If the cost and delay metrics are proportional, the offline version of COST DISTANCE has constant factor approximation [6, 21] and there is an ....

[Article contains additional citation context not shown here]

M. Andrews and L. Zhang. The access network design problem. 39th IEEE Symposium on Foundations of Computer Science, pages 40--49, 1998.

....explanation of what the properties states. A precise de nition of the syntax and semantics of CTL operators is given in Section 3. AGF P Model checking algorithms for verifying CTL properties of nite state transition systems are well studied [7] Moreover, subsets CTL [4, 5] and LTL [22] of CTL have also been formulated and thoroughly investigated. Symbolic model Partially supported by the UNU IIST o shore project Semantics and veri cation of realtime programs using Duration Calculus: Theory and Practice 1 checking algorithms for verifying formulae of these sub logics have ....

A. Pnueli, The Temporal Logic of Programs, 18th IEEE Symposium on Foundations of Computer Science, 1977. 15

....therefore, we need to define a provisioning constraint that disables DC and DOS. One method to specify this property is to use a simple form of linear temporal logic. Temporal logic, introduced in the late seventies for the concise formulation of correctness properties of concurrent systems [P77], defines a small number of operators that allow us to reason about executions. In temporal logic the example property can be specified as follows: offhook X ( dialtone onhook) In this case we allow for the possibility that the subscriber returns the phone onhook before actually hearing ....

Pnueli, A., The temporal logic of programs. Proc. 18th IEEE Symposium on Foundations of Computer Science, 1977, Providence, R.I., pp. 46-57.

.... In synchronous models like CCS and calculus, this characterization is provided by trace equivalence [14] that just requires two equivalent processes to be able to perform the same sequences of actions (traces) Trace equivalence is widely used outside the process algebra world (see, e.g. [33, 27, 28]) and has a great relevance from a practical point of view. Coincidence with may testing is important also because it provides a full justification of trace equivalence in observational terms. This coincidence fails to hold in the asynchronous case. For instance, the equation a:b:P = b:a:P , ....

A. Pnueli. The Temporal Logic of Programs. Proc. of the 18th IEEE Symposium on Foundations of Computer Science, pp.46-57, IEEE Computer Society Press, 1977.

....more than n states, over a mutual alphabet Sigma with p letters, we want to check if there is a sequence accepted by both P and B. The automaton P accepts the bad computations, i.e. those that are not allowed. Thus, if the property is given originally e.g. using a linear temporal logic (LTL) [17] property , then P is the automaton corresponding to : For an efficient translation from LTL to automata, see e.g. 6] The following simple theorem demonstrates that the current problem is at least exponential in time in the size of the automaton B. Theorem 2 The deterministic time ....

A. Pnueli, The temporal logic of programs, 18th IEEE symposium on Foundation of Computer Science, 1977, 46--57.

....will give an example of such a property later in this paper. In its most general form, Spin supports the automated ver 4 Holzmann, Smith ification of properties stated in linear temporal logic, a standard method for specifying properties of concurrent systems introduced in the late seventies [7]. 4 An Example For an application of these ideas, we studied Lucent s Actiview Provisioning offering for Wireless operators. Actiview is a workflow management product sold in a number of markets, such as ffl Commercial local exchange carriers, ffl Wireless service providers, ffl Domestic local ....

A. Pnueli, 'The temporal logic of programs,' Proc. 18th IEEE Symposium on Foundations of Computer Science, 1977, pp. 46-77.

....however, fully convinced that the addition of an appropriate version of overlapping states to the basic formalism will greatly enhance its potential. i[5 Fig. 45. 6.3. Incorporating temporal logic Temporal logic (TL) is used quite extensively in the specification of concurrent programs; see [24, 27]. We are of the opinion that TL can be used beneficially together with statecharts in more than one way. It is possible to specify ahead of time many kinds of global constraints in TL, such as eventualities, absence from deadlock, and global timing constraints. Then one would carry out a ....

A. Pnueli, The temporal logic of programs, Proc. 18th IEEE Symposium on Foundations of Computer Science (1977) 46-57.

.... model checker SPIN [12] 1 Until now, to user of a model checking system will typically manually define an abstract model that captures the essential aspects of an application [2] 13] Properties can then be formulated as assertions, or more generally as formulae in propositional temporal logic [20]. SPIN can perform either an exhaustive check that proves whether or not the model satisfies the property, or it can deliver a best effort estimate of this fact within given time or memory constraints. For reasonable constraints (e.g. given a memory arena of around 64 Megabytes, and a runtime ....

A. Pnueli, The temporal logic of programs. Proc. 18th IEEE Symposium on Foundations of Computer Science, 1977, Providence, R.I., pp. 46-57.

....resources. There is a class of problems, though, for which effective tool support can been developed. We will review the automata theoretic verification method, as formulated by Moshe Vardi and Pierr Wolper [13] and the use of propositional linear temporal logic, as first proposed by Amir Pnueli [11]. The automata theoretic method for temporal verification meshes well with verification methods based on graph exploration algorithms. A number of practical issues must be resolved, though, before this method can be applied for the verification of distributed software applications. We will ....

Pnueli, A. The temporal logic of programs. Proc. 18th IEEE Symposium on Foundations of Computer Science, 1977, Providence, R.I., pp. 46-57.

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A. Pnueli. The Temporal Logic of Programs. Proc. of the 18th IEEE Symposium on Foundations of Computer Science, pp.46-57, IEEE Computer Society Press, 1977.

No context found.

Pnueli, A., The Temporal Logic of Programs, 18th IEEE Symposium on Foundations of Computer Science, 46-57. Oct. 1977.

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