Lucent Technologies Inc.

Rakesh Kumar Sinha

David Y Lee

Ruibing Hao

Randeep Singh Bhatia

Yihao Lisa Zhang

Chung-Min Chen

Dario Vlah

Ayse Funda Ergun

A method of generating a set of test sequences for evaluating interoperability of a number of interconnected communication systems with respect to a desired mode of communication between a first end user and a second end user. A number of operational states that are required of the communication systems to implement the desired mode of operation between the two end users is determined, wherein each state pertains to a first operation of a first gateway system associated with the first end user and a corresponding second operation of a second gateway system associated with the second end user. The interconnected communication systems are tested by causing the systems to perform specified transitions between pairs of at least some of the operational states.

Generation of test suites for interoperability of reactive communication systems

A network router is tested for operation according to a given network protocol, by coupling the router under test (RUT) to a test host device and arranging the device to simulate operative test network topologies which include router nodes, network nodes, and edges between the nodes. The device exchanges information packets with the RUT for each of a number of successive test network topologies. Each successive topology is determined randomly by inserting or deleting an edge or a node to or from a prior test network topology in a probabilistic manner. Operation of the RUT under the given protocol is evaluated based on the exchanged information packets. A judgment, e.g., a fault or a no-fault condition, is rendered by the host device.

Testing of network routers under given routing protocols

A method of determining an optimal path from a source node to a destination node over a number of links in an information network having n nodes. Each link has an associated cost-delay function, the optimal path is constrained to an overall delay of D, and a total cost of all links along the path is to be minimized at a value OPT. The method includes maintaining a range &lsqb;L, U&rsqb; for OPT, wherein L is a lower bound and U is an upper bound, and setting initial values for L and U. A cost value V is set corresponding to {square root over (U&middot;L)}, and a scaled cost c&prime; is derived for each link wherein c&prime; corresponds to cn/V&egr;, c is an actual cost for each link, and &egr;>0. If a feasible path having a delay of at most D and a total cost of at most V is found not to exist, then the value of L is increased to V, a new cost value V is set and the link costs c&prime; are further scaled. The values of L and U are reset until U/L<2 and a feasible path continues to exist. The links of the feasible path are then identified as the optimal path using the last-scaled link costs.

Quality of service routing in information networks over paths having performance-dependent costs

A method of declustering data among a number of storage units, e.g., disks, to minimize response time for range queries. Data to be stored is identified in the form of a dataset, wherein the data is divided among uniform data blocks (x, y) and each data block is to be stored in one of a number (M) of storage units each of which has an associated seek time. M pairs (i, key ) are defined wherein i&equals;0,1, . . . m&minus;1 and key is the fractional part of 2i/(1&plus;5). First components of the pairs are ordered according to an ascending order of the key values of the pairs, thus defining a permutation array A of size M. Another permutation array B is defined such that for i&equals;0,1, . . . ,M&minus;1 B&lsqb;a(i)&rsqb;&equals;i, and data block (x,y) is assigned to storage unit (x&minus;B&lsqb;y mod M&rsqb;)mod M, wherein mod is the remainder function.

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Manville, NJ, United States of America

Rakesh Kumar Sinha