Abstract: The invention provides a method for compacting transactions which have committed at a disconnected client prior to sending the transactions to the server for replaying along with an iterative process for re-calculating the combined transaction in the event that replay at the server fails.

Abstract: The present invention addresses the issue of controlling delay variations (jitter) in packet-switched networks by enhancing the capabilities of existing scheduling policies. The idea is to use a few bits in the header of packets to send jitter control information to the downstream network elements, so that the delay variation caused by the upstream network element, is compensated for by the downstream network element. The key point to observe is that packets (or cells in ATM) may be small, and therefore, not contain many bits in the header that can be used for jitter control. We describe a unique scheme, that utilizes the bits that are available for jitter control in an efficient manner, allowing for the desired jitter to be obtained with as few bits as possible.

Abstract: A method and apparatus for delivering multimedia video data from a server (host processor) to a plurality of clients connected to a communications network. More specifically, with this invention, preprocessed video and multimedia data packets are striped across disks in units of fixed playback time, even if such units result in variable length stripes. To deliver multiple video or continuous media streams, the disks in the array are accessed simultaneously so that at any given instance, different disks are accessing the video or multimedia data for different streams. Access to the disks for reading the continuous media files is scheduled periodically, with the period equal to the back time of the stripes. Because each disk read command retrieves data for a fixed play back time, if the first read command for a continuous media stream request can be scheduled to complete on a disk within a playback time, all subsequent read commands are also guaranteed to not interfere with read commands of other streams.

Abstract: A thin film transistor having two vertically stacked channels and dual gate non-photosensitive structure, where the source drain to bottom gate structure is self-aligned. This structure occupies the same area on a substrate as a conventional single gate thin film transistor. This invention also discloses a process for manufacturing a dual gate structure with a simple three mask procedure.

Abstract: A mechanism to dynamically migrate a home node of a global page to a more suitable node for improving performance of parallel applications running on a S-COMA and other DSM systems. More specifically, consultation counts are maintained at each client node of a shared memory system, where the consultation count indicates the number of times the client node has consulted the dynamic for lines a page. This information is then used along with other information to decide on whether to change the dynamic home node to a more suitable node.

Abstract: A method and an apparatus for protecting selected files in a portable computer system. With this invention a user selects a set of riles on a hard disk of the system for protection. This invention uses an encryption key, a secret key and an algorithmic transform to protect the selected files. With this invention the selected files are encrypted with the encryption key, and two copies of the encryption key are scrambled, one with the secret key and one with the transform of the secret key. Then, both scrambled versions of the encryption key are stored on the hard disk. When the user enters the secret key, the two scrambled versions of the encryption key are unscrambled using the key entered by the user and by using the transform of the key entered by the user. These unscrambled versions are then compared. If these unscrambled versions match, the original encryption key has been correctly restored and selected files will be decrypted either immediately or when referenced by an application program.

Abstract: A system and method for compressing a data sequence having a plurality of records, where each record has a plurality of fields with each field being arranged to contain a data item. The system compares a data item in a current field of a current record with a data item of a corresponding field of a preceding record. If there is a match, the current data item is replaced by a token indicating the match.

Abstract: A cache coherence protocol for a multiprocessor system. Each processor in the system has an associated cache capable of storing multiple word data lines. The system also includes a plurality of main memory modules, each having an associated distributed global directory storing directory information for lines stored in the associated main memory module. Each main memory module is connected to each processor by means of a multi-stage interconnection network. When a processor attempts to over-write an individual word in a line stored in its associated cache, a write request signal is sent to the appropriate global directory, and each other processor whose cache stores a copy of the line is notified of the request. When each other processor has responded with an acknowledgement, the first processor is allowed to proceed with the write.

Abstract: A spatial light modulator designed to use a minimum area on the surface of a silicon substrate. This invention comprises a silicon substrate on a back plate with a glass cover that is used to seal liquid crystal between the glass cover and the silicon substrate. Most importantly, the glue seal formed to contain the liquid crystal material is between the cover glass plate and the Si substrate on only one side and the back plate on the remaining three sides. This structure allows a smaller semiconductor substrate to be used.

Abstract: In a wireless multi-rate communications system, a method for extending the range of communications in the system by dividing the physical layer frame into two portions: a robust header portion and a body, where the repetition rate of the data symbols in the header portion is greater than or equal to the repetition rate of the data symbols in the body of the frame. In this way the header can be received and decoded by all stations in the system with a high probability, while the body of the frame need only be received and decoded by the destination station to which the body of the frame is intended to be received and decoded.

Abstract: In a distributed computing environment, in which a client needing to access a server is issued, by a security server, with a ticket including an encoded certificate identifying, when decoded, the identity and privilege attributes of the client in a format understood by a server within the environment, access to a resource external to the environment through such a server within the environment is provided, when a request involving such access is received by the security server, by issuing an extended certificate including additional data which can be decoded to provide information decoded as to the identity and privilege attributes of the client with respect to and in a format acceptable to the external server, the additional data being recognized and decodable and formatable by that server within the environment which provides access to the external server, but transmitted within the environment in a format compatible with the certificates in regular tickets.

Abstract: A method of reconfiguring a multipoint communications channel to reconnect selected nodes after failures occur in the network disclosed. The method for this invention requires that a selected node (leader) participating in the multipoint communication channel act as the coordinator of the re-establishment protocol. The coordinator (leader) monitors the state of network topology to determine failures, recomputes an alternative feasible communication channel path in the case of failure, and generates messages to join new network elements in the multipoint communication channel. By using a novel tree recomputation method that rejoins the disconnected subtrees created by the network failure to the tree containing the coordinator, along with network topology information, the coordinator is able to minimize messaging and preserve the original channel to the maximum possible extent.

Abstract: A method and apparatus for maintaining cache coherence in a shared memory multiprocessor system, where cache coherence is preserved between lock acquires and releases rather than at every single memory load and store. With this invention, a Global Lock Manager (GLM) keeps track of the status of locked ranges without the need to maintain a list of individual processors in the system. Further a Recently Acquired Lock Manager (RALM) keeps track of the status of locked ranges within a processing node to reduce the need to communicate with a GLM.

Abstract: The present invention relates to the issue of providing end-to-end delay guarantees in a multi-node communication system. More specifically, the present invention addresses the problem of specifying operational parameters of rate-controlled service disciplines in a communication network in order to efficiently provide end-to-end delay guarantees. The key contribution is a method for specifying leaky bucket parameters as well as scheduling delays at each node, which are used as inputs to the rate-controlled service discipline.

Abstract: A thin film transistor having two vertically stacked channels and dual gate non-photosensitive structure, where the source drain to bottom gate structure is self-aligned. This structure occupies the same area on a substrate as a conventional single gate thin film transistor. This invention also discloses a process for manufacturing a dual gate structure with a simple three mask procedure.

Abstract: A method and apparatus for compressing video data to improve its tolerance to error, especially with a low bit rate network. With this invention video data is divided into a number of frames and each frame is divided into a number of macroblocks. A dependency count is assigned to each macroblock, and if the dependency count for the macroblock exceeds or is equal to a threshold, the dependency block is intra-coded using low bit rate coding algorithm. If the dependency count is below the threshold, the macroblock is inter-coded.

Abstract: A wiring scheme for providing loop-back capability for individual failed channels around a ring network composed of nodes with limited space-switching. With this invention each node has a switch for interconnecting channels between incident links of the node. Each secure channel i has a backup channel B(i). In the normal mode of operation, the switch is configured so that the ports for channel B(i) of the incident links are connected to each other. Upon failure of channel i in one of the incident links of the node, the port for channel i of the failed link is connected to the port for channel B(i) on the other incident link of the node. With this invention when there is a failure of channel i on one of the links, the connection using this failed channel can be restored by switch configurations at only two nodes of the ring since the backup channels at the other nodes are already connected to each other.

Abstract: The building, maintenance, and use of a database is described having a trie-like structure for storing entries and retrieving an at least partial match, preferably the longest partial match, or all partial matches of a search argument (input key) from said entries, said database having nodes (20), with each node containing first link information (21) leading to at least one previous node (parent pointer) and second link information (25,26) leading to at least one following node (child pointer), at least a stored key (entry, 23, 24), or a combination, thereof. The particular structure of the nodes allows a two-step search process, in which segments of a search argument are firstly used to determine a search path through the trie-like database, said search path being backtracked in the second part of the search. During the second part of the search the entire search argument is compared to entries stored in the nodes until a match is found.

Abstract: A highly sensitive optical receiver where one terminal of the photodiode of the receiver is connected to a negatively biased amplifier while the other terminal of photodetector is connected to a positively biased amplifier, where such connections automatically bias the photodiode and use the current from both terminals (anode and cathode) of the photodiode. This invention also provides an optical receiver which has a DC cancellation circuit to eliminate the biasing voltages in the final output signal.

Abstract: A method and apparatus for expanding the physical coverage area of a wireless communications network. More specifically, a number of transceivers are connected in a series configuration to a single base station, and each transceiver transmits signals to selected portions (subcells) of the physical coverage area. Each transceiver is connected to a delay unit where all of the delay units are adjusted so that downlink signals transmitted from the single base station will be transmitted from the transceivers to their respective subcells in phase with each other. Since all of the downlink signals from each of the transceivers result from the same downlink signal from the base station and since they are in phase with each other, a wireless unit anywhere in the physical coverage area will receive a downlink signal which is error free.