Lucent Technologies Inc.

Other

Alcatel-lucent USA Inc.

Bell Communications Research, Inc.

Peter M Winkler

Thomas J Richardson

Kevin R Curtis

Gordon Thomas Wilfong

Clifford Eric Martin

Michael C Tackitt

Kin K Leung

Markus Andreas Hofmann

Francis Xavier Zane, Jr

David James Houck, Jr

Aravind Srinivasan

Yacov Yacobi

Arjen K Lenstra

Barnet M Schmidt

Penelope E Haxell

Bruce Shepherd

Matthew Andrews

A system and method are disclosed for time-domain wavelength interleaved networking that reduce the need for complex time-slot scheduling and reduce the routing complexity. Substantially all communications in the time-domain wavelength interleaved network pass through a hub node. In addition, interior nodes in the time-domain wavelength interleaved network will forward substantially all communications received from the hub node that are destined for another node on all branches outward from the hub node. The central hub node can impose a timing reference. Thus, the transmission and reception of a message can be synchronized such that a message sent in a time-slot k by a node Nwill be received by a node Nin the time-slot k. Further, the hub node can recover from a link failure by shifting transmission times of all nodes that are separated from the hub node by the failed link.

Time-domain wavelength interleaved network with communications via hub node

A scalable system and method for locating a closest server in response to a client request via an interactive distribution network, such as the Internet, are provided. A closest content server is defined as having the least round trip time for responding to a client request. The system including a plurality of content servers; and a local server in communication with a plurality of clients, the local server acting as a proxy for communicating client requests from clients to a redirection server. Client network distance and load information is periodically collected at each content server in the network from clients communicating with each of the respective content servers. The redirection server periodically aggregates the network distance and load information from each content server to create client clusters from both current and previously aggregated network distance and load information. Each client cluster represents a division or partition of the total IP address space. Each client cluster is then mapped (paired) to one or more content servers in the network. The mapping or pairing is then utilized to respond to client DN requests received from any client in the network. Another aspect of the invention involves considering the respective capacities of the content servers in the network. A selection probability is assigned to each content server/domain index pair to prevent the repeated selection of the content server having lowest round trip time thereby overloading that server's service capacity. The selection probabilities assigned to each content server effect a load balancing to prevent overloading. Another aspect of the invention involves collecting the distance and load information without incurring any overhead cost by passively collecting TCP information as it is transmitted from clients in communication with content servers in the course of normal communications.

System and method for locating a closest server in response to a client domain name request

We disclose a method for routing a set of demands in a ring network that comprises nodes interconnected by directed links, in which each demand may be routed clockwise or counterclockwise. According to our method, a linear program is solved to obtain a set of routing variables that minimize an objective function. Each routing variable corresponds to a respective one of the demands, and has a value, exemplarily, on the closed interval from 0 to 1. A value of 1 signifies, e.g., clockwise routing, and a value of 0 signifies counterclockwise routing. The objective function describes the value of a load, defined on each link and maximized over all links of the network, so that a solution of the linear program provides a minimum value of the maximized load. The method further comprises rounding the routing variables so that the value of each routing variable falls at 1 or 0. This rounding is carried out such that the maximized load does not exceed the previously-obtained minimum value of the maximized load. The method further comprises routing each of the demands clockwise or counterclockwise, in accordance with the value of its respective routing variable.

Routing method for ring networks, such as WDM ring networks for optical communication

A system and method for providing automatic path selection in a fiber-optic transmission network. The system provides efficient utilization of available bandwidth with respect to T1, T3 and STS-3c service requests. A time slot is selected from the available time slots in a maximally utilized and efficient manner in response to a type of service request. The time slot is then assigned to the service request to provide a transmission pathway. In response to a T1 service request, the system finds the most occupied time slot which has an available assignable time slot. If a new unoccupied time slot is required or the request is for a T3 or a STS-3c service, the system selects an unoccupied time slot in accordance with a prioritized order of contiguous unoccupied time slots.

Automatic path selection for fiber-optic transmission networks

A data synchronization system, which in one embodiment, uses a ShuffleNet topology requiring an even number, N=2m, of nodes in the system. These nodes are organized into two sets, X=x.sub.0, . . . , x.sub.m-1 and Y=y.sub.0, . . . , y.sub.m-1, wherein the subscripts are always to be taken modulo m. Each 'round' of communication entails simultaneously synchronizing the nodes in X with nodes in Y according to a matching between the two sets. The rounds are grouped into two 'batches,' batch B.sub.j which consists of rounds R.sub.2j-1 and R.sub.2j-2 for j.gtoreq.1. During each odd batch B.sub.2j-1, each x.sub.i synchronizes with y.sub.2i+2j-2 and with y.sub.2i+2j-1. In another embodiment, the data synchronization is based on a hypercube scheme, wherein each node is labeled by a binary string and any two nodes with their labels differing by one bit are connected by an edge and only adjacent nodes, i.e. those nodes connected by an edge, can communicate and exchange data directly according to an update schedule. In a third embodiment, a hypercube scheme is used, but the number of nodes is assumed to be a power of 2 or N=2.sup.m. This embodiment, like the second embodiment, uses the labeling of nodes by their binary representation, but the matchings of nodes used to determine the update schedule is not confined to the hypercube edges. Instead, a general cyclic matching scheme is used.

Synchronization methods for distributed processing systems having

Bit error rate in holographic storage/reconstruction is reduced by 2-dimensionally dispersing symbols constituting codewords so that no two codeword-common symbols occupy a single row or column on the SLM display.

Holographic storage of digital data

Bit error rate of an output data stream, reconstructed from a holographic recording, is reduced by reducing the length of same-state pixels on the spatial light modulator.

Bit error rate reduction by reducing the run length of same-state pixels

A key escrow technique is disclosed which permits cryptographic limits on wiretapping warrants. Specifically, time limits on wiretaps may be enforced. In addition, the wiretapper is targeted to a specific party or specific pairs of parties communicating in a network.

Key escrow method with warrant bounds

A portable electronic device for comparing and then destroying information, comprising a keyboard for input of information by two or more users, a microprocessor for comparing the information and then destroying it, and a visual display for revealing the results of the comparison; whereby each user may enjoy the results of the comparison and still be assured that his or her own information remains private, and cannot be extracted from the device either during use or at any later time. In its preferred embodiment the device looks rather like a hand calculator with alphanumeric keyboard, but has a cover with a shield attached, permitting privacy in use of the keyboard. Among the tasks which the device can perform are matching, that is, testing to see if two or more users have input identical information; ranking of users according to numerical input; and tallying of votes. Applications envisioned include password exchange, gossiping, secret ballot voting, boardroom polling, bidding, secret comparison, overcoming shyness, police interrogation and adult games.

Growing community of inventors

Madison, NJ, United States of America

Peter M Winkler