Matsushita Electric Industrial Co., Ltd.

Panasonic Technologies, Inc.

Ibrahim Mostafa Kamel

Walid G Aref

Sarit Mukherjee

Daniel Barbara

Shahram Ghandeharizadeh

Rafael Alonso

Khaled Elbassioni

Thirumale N Niranjan

Dennis Bushmitch

David Alan Braun

Mahfuzur Rahman

Cuneyt Akinlar

Li Zou

Beizhong Chen

Prasant Mohapatra

Padmavathi Vallabhaneni

An apparatus for ensuring quality-of-service in a network is provided. A first stream sender having a flow control parameter and transmitting a first stream. A network interconnection receiving the first stream and a second stream. First stream being a non-realtime stream and the second stream being a realtime stream. A bandwidth control being associated with the network interconnection. The bandwidth control adjusting the flow control parameter for supporting quality-of-service parameters associated with the second stream.

Quality of service management in network gateways

An area is divided into regions or cells each having an associated multicast group address. The cells are organized using a quad-tree data structure that is dynamically updated. Mobile entities within a given cell elect one of their members as coordinator for assessing cost data associated with subdividing or merging the cell with other sibling cells. The coordinators communicate this cost data to a partitioning entity, which may be a central server, that computes a new partition scheme using a greedy algorithm. The new partition scheme is then broadcast to the mobile entities for use in subsequent communication. Mobile entities join multicast groups that intersect with their individual vision domains. In this way, mobile entities can acquire information from other mobile entities without the need to monitor all multicast group transmissions.

Dynamic multicast grouping for vehicles and other mobile objects

A method is provided for managing memory resources in a service gateway environment. The method includes: receiving a service request, the service request having an associated memory space requirement that exceeds total available memory space associated with the gateway environment; determining a number of dependent service instances for each service instance; determining an accumulative memory space requirement for each service instance; identifying a subset of service instance whose memory space requirement exceeds the memory space requirement of the service request, the subset having a minimal number of the service instances; and performing a memory resource management operation in relation to the identified subset of service instances.

Efficient service management in home gateways

The client application provides VCR functionality in a data-centered video multicast network () through active prefetching of the fragments from broadcast channels. The player () has a user interface () that supports a plurality of VCR functions (). Plural buffers () and their associated loaders () download video data under control of a manager module (). The manager module accesses the playback pointer () and employs feasible point calculation module () to cause the loaders to selectively download segments so that VCR functions can be supported while maintaining continuous playback after the VCR function is performed.

Providing VCR functionality for data-centered video multicast

The disk scheduling algorithms try to service a request with lower priority and strict deadline only if serving this request is not going to violate the deadline constraints of a higher priority request. One of the algorithms uses a single queue to hold all the requests regardless of their priority. The single queue is reorganized after the arrival of a new request according to the order requests would be serviced. A second algorithm uses multiple queues. Each queue holds only requests with the same priority, and the requests in each priority queue are sorted according to their deadlines. The decision of servicing a request is made at scheduling time.

Providing quality of service for disks I/O sub-system with simultaneous deadlines and priority

A distributed file system using autonomous disks is disclosed. The file system includes autonomous data disks that store the application data of the distributed file system. Legacy attribute disks store the file system's meta-data and directory structure. The directory structure is stored on the legacy attribute disks using the native file system. One of the clients of the file systems is utilized as a configuration manager to control access to the system. The distributed file system employs agents to support real-time applications and concurrent read/write to files.

Real-time distributed file system

A computer-implemented scheduling method and apparatus for scheduling operations relating to a predetermined activity. The activity includes scheduling operations of network-attached storage devices, or other computer-related operations, or non-computer related operations, such as manufacturing plant operations. Operational data is received that is indicative of the operations. Attributes regarding the received operational data are identified. A linear ordering of the attributes is imposed via a predetermined curve. The curve is an aggregation of at least substantially continuous functions from intervals so as to form a substantially repetitive pattern. Operations are scheduled based upon the imposed linear ordering. With such an approach, the overall performance aspects of the system is significantly improved.

Scheduling method and apparatus for network-attached storage devices and other systems

A multi-media file system for conmmunicating information between a multi-media client and a network storage device over a network. The file system includes a cluster that comprises one cluster manager and at least one file manager with each network storage device. The cluster manager is located on a client, includes an admission controller for controlling the admission of a request from a client for a file operation upon a selected file. A network bandwidth request from the admission controller is responded to by a network status determiner included in the cluster manager. The network status determiner determines the available network bandwidth. Each file manager is located on one of the clients. The file managers manage file maintenance procedures of corresponding files located on the network storage device. Each file manager includes a disk status determiner for determining the available disk bandwidth. The disk status determiner responds to a request from the admission controller.

Multimedia file systems using file managers located on clients for managing network attached storage devices

A process is presented for supporting simultaneous disk read and write requests in a video server environment. Read requests are the result of movie viewing, while write requests are the result of video clip editing or movie authoring procedures. Due to real-time demands of movie viewing, read requests have to be fulfilled within certain deadlines, otherwise they are considered lost. Since the data to be written into disk is stored in main memory buffers, write requests can be postponed until critical read requests are processed. However, write requests still have to be proceeded within reasonable delays and without the possibility of indefinite postponement. This is due to the physical constraint of the limited size of the main memory write buffers. The new process schedules both read and write requests appropriately, to minimize the amount of disk reads that do not meet their presentation deadlines, and to avoid indefinite postponement and large buffer sizes in the case of disk writes.

Video server scheduling for simultaneous read-write requests

Multi-media servers provide clients with streaming data requiring soft real-time guarantee and static data requiring a large amount of storage space. The servers use a pull-mode protocol to communicate with clients through a real-time network. Separate data and control channels enhance the soft real-time capability of the server. The data channel conforms to open standard protocol. A switched data link layer for the control channel permits separate intrahost control messages that may be multicast and broadcast. The distributed file system selects a specific data block size based upon the compression technique employed to enhance soft real-time guarantee. A hierarchal data structure combined with merging empty data blocks minimizes disk fragmentation. Data blocks are striped across multiple disks to improve disk utilization. A local buffer and a queue for both read and write requests provides support for simultaneous read and write data streams.

Inexpensive, scalable and open-architecture media server

A transport system allows delivery of MPEG video streams from a network server to a media client while avoiding network delays associated with transition between files contained in these streams. A buffering system, a transport controller, and a counter allow buffering and interim delivery of MPEG stream data. The transport controller can either deliver MPEG stream data directly to the media client, or route data through the buffering system. The buffering system includes a population buffer for storage of interim MPEG stream data, and a transport buffer for temporary storage of MPEG stream data during continuous delivery. During transitional delivery, the transport controller delivers interim data to the media client until the requested file is available and uses the counter to select the proper start location in the requested file.

Algorithm for fast forward and fast rewind of MPEG streams

A single queue is utilized for scheduling of prioritized requests having specific deadlines in which to be serviced. New requests are initially inserted into the single queue based upon optimal SCAN order. Once the new request is inserted, the deadlines of all the requests in the queue are checked in order to insure each request deadline is met. In the event a deadline violation is identified, the queue is reorganized by identifying the lowest priority request currently to be processed prior to the request with the deadline violation. If more than one request with the lowest priority exists, the lowest priority request with the greatest deadline slack is selected. Ultimately, the selected request is moved to the tail of the queue, or removed from the queue and considered lost if its deadline is violated with a queue tail placement. This process is repeated until the queue is in a state with no deadline violations.

Real time scheduling of prioritized disk requests

The distributed multimedia server employs modular server elements that connect with client systems through a high bandwidth network. The server elements are connected in interleaved fashion with the switching elements and the data representing different media selections are arranged in stripe groups distributed across the server elements. The server can be as small as a single server element or grown incrementally, as needed, by connecting additional server elements to the system. Multiple copies of hot media selections are stored across the distributed architecture within different stripe groups to minimize bottlenecks within the storage subsystem.

Seamless scalable distributed media server

The disk scheduling system supports the processing of simultaneous storage device read and write requests in a video server environment, thereby supporting both video-on-demand and non-linear editing applications. Read requests are the result of movie viewing, while write requests are the result of video clip editing or movie authoring procedures. Due to real-time demands of movie viewing, read requests have to be fulfilled within certain deadlines, otherwise they are considered lost. Since the data to be written into the storage device is stored in main memory buffers (or write buffers), write requests can be postponed until critical read requests are processed. However, write requests still have to be proceeded within reasonable delays and without the possibility of indefinite postponement. This is due to the physical constraint of the limited size of the main memory buffers. The new process treats both read and write requests in a homogenous manner in order to ensure that the deadlines are met and avoids indefinite postponement and large buffer sized in the case of storage device writes utilizing a single queue of requests.

Simultaneous processing of read and write requests using optimized

A data organization scheme for movies stored on a video server. The method utilizes the available bandwidth and space in the I/O system to avoid the data contention in the ATM. Basically, parts of the hot movies are replicated on the server unit. Most of the requests to the hot movie are directed to this unit. But if the server unit can not deliver the required video object within the required time limit (because of the large queue length) the video object is transported from the other server units through the ATM network. All the requests that are fulfilled locally by the server unit will not go through the network. Thus, the traffic through the ATM decreases on the expense of increasing the disk utilization.

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Monmouth Junction, NJ, United States of America

Ibrahim Mostafa Kamel