Abstract: It can be determined whether relative one way delay for data packets in a data stream exceeds a delay threshold. If so, then a delay congestion signal indicating that the relative one way delay exceeds the delay threshold can be generated. The delay congestion signal can be used in calculating an adaptive bandwidth estimate for the data stream. A packet loss rate congestion signal may also be used in calculating the bandwidth estimate. It can be determined whether a data stream of data packets is in a contention state. If the data stream is in the contention state, then an adaptive bandwidth estimate can be calculated for the data stream using a first bandwidth estimation technique. If the data stream is not in the contention state, then the bandwidth estimate for the data stream can be calculated using a second bandwidth estimation technique.

Abstract: Methods and systems for routing video in conferencing are disclosed. A device receives one or more data streams from a media source, where each data stream associated with a data stream identifier. A media source identifier is assigned to each data stream from the media source. The data stream identifiers are mapped to the media source identifiers. At least one of the data streams may be modified by replacing an associated data stream identifier with the media source identifier. The modified data streams are provided to a destination device. A request is received from a destination device for data streams associated with a media source identifier. One or more data stream identifiers are associated with the requested media source identifier. The one or more data streams may be associated with Application sharing/Desktop Sharing, a video quality, a video resolution, a video frame rate, or an audio quality.

Abstract: Embodiments of methods and systems for dominant speaker identification in video conferencing are described. In one embodiment, the computer-implemented method includes identifying one or more dominant speakers in a video conference. The method may also include generating a list of the one or more dominant speakers. Additionally, the method may include communicating the list of one or more dominant speakers to clients in a video conferencing system. In a further embodiment, the method includes communicating the list of the one or more dominant speakers to a client in response to the client joining the video conference.

Abstract: Methods and systems for routing video in conferencing are disclosed. A device receives one or more data streams from a media source, where each data stream associated with a data stream identifier. A media source identifier is assigned to each data stream from the media source. The data stream identifiers are mapped to the media source identifiers. At least one of the data streams may be modified by replacing an associated data stream identifier with the media source identifier. The modified data streams are provided to a destination device. A request is received from a destination device for data streams associated with a media source identifier. One or more data stream identifiers are associated with the requested media source identifier. The one or more data streams may be associated with Application sharing/Desktop Sharing, a video quality, a video resolution, a video frame rate, or an audio quality.

Abstract: A video conference cross-links at least a portion of the clients for point to point communication while still using a video conference server. The video conference server continues to manage some aspects of the video conference for the cross-linked clients and may be configured to perform audio/video processing for some of the clients in a video conference. For example, the video conference server may perform audio/video processing and routing of streams for clients that do not have the capabilities to perform the processing directly. Clients that are able to process their audio/video needs may directly connect to other clients through cross-links while still using the video conference server for management.

Abstract: Accordingly a method and interface allows an attribute data base used by an Information Manager to be quickly populated and accurately maintained. A single Bulk Attribute Retrieval Request triggers the primary storage device to collect object attribute information. The method allows for selective collection of objects and attributes by providing filters and attribute lists in the Requests. The Request may be used to provide an incremental scan with appropriate time stamp filtering. In addition, the size of the results can be controlled by the IM by eliminating attributes that are not of interest to the IM. The Request is advantageously issued over a FileMover interface, which is an HTTP connection, and encoded in XML, allowing the IM to easily customize the Request as desired.

Abstract: It can be determined whether relative one way delay for data packets in a data stream exceeds a delay threshold. If so, then a delay congestion signal indicating that the relative one way delay exceeds the delay threshold can be generated. The delay congestion signal can be used in calculating an adaptive bandwidth estimate for the data stream. A packet loss rate congestion signal may also be used in calculating the bandwidth estimate. It can be determined whether a data stream of data packets is in a contention state. If the data stream is in the contention state, then an adaptive bandwidth estimate can be calculated for the data stream using a first bandwidth estimation technique. If the data stream is not in the contention state, then the bandwidth estimate for the data stream can be calculated using a second bandwidth estimation technique.

Abstract: Tools and techniques for determining conditions of conferences include calculating a global conference parameter that represents a rate at which several different conferences are processed. The machine may also calculate individual conference parameters representing a duration of time spent in processing the conferences considered individually.

Abstract: A video conference cross-links at least a portion of the clients for point to point communication while still using a video conference server. The video conference server continues to manage some aspects of the video conference for the cross-linked clients and may be configured to perform audio/video processing for some of the clients in a video conference. For example, the video conference server may perform audio/video processing and routing of streams for clients that do not have the capabilities to perform the processing directly. Clients that are able to process their audio/video needs may directly connect to other clients through cross-links while still using the video conference server for management.

Abstract: Technologies are described herein for detecting and managing congestion on a shared network link. A determination is made whether the shared network link is congested based on loss rate and round-trip time (RTT) between a computer and a receiver operatively coupled by the shared network link. Upon determining that the shared network link is congested, a back-off operation is performed on the computer. The back-off operation may reduce an allocated bandwidth of the computer on the shared network link by transforming a higher allocated bandwidth into a lower allocated bandwidth.

Abstract: A storage object such as a virtual disk drive or a raw logical volume is contained in a UNIX compatible file so that the file containing the storage object can be exported using the NFS or CIFS protocol and shared among UNIX and MS Windows clients or servers. The storage object can be replicated and backed up using conventional file replication and backup facilities without disruption of client access to the storage object. For client access to data of the storage object, a software driver accesses the file containing the storage object. For example, a software driver called a virtual SCSI termination is used to access a file containing a virtual SCSI disk drive. Standard storage services use the SCSI over IP protocol to access the virtual SCSI termination. An IP replication or snapshot copy facility may access the file containing the virtual SCSI disk drive using a higher-level protocol.

Abstract: Tools and techniques for application-specific heap management are described herein. The tools may provide machine-readable storage media containing machine-readable instructions for profiling an application to facilitate managing heap memory associated with the application, and for managing requests from the application to allocate or deallocate from the heap memory based on the profiling. The tools may also receive requests from the application to allocate buffers, and may determine whether an instance-level memory pool, which is associated with a portion of the application, contains enough free buffers to satisfy the request. Finally, the tools may receive requests from the application to deallocate buffers, and in response to the request, may deallocate the requested buffers into the instance-level memory pool. The tools may also determine whether the instance-level memory pool contains a number of free buffers that exceeds a threshold.

Abstract: A method and apparatus for performing incremental file system checks is described which uses file system information to identify changes that have occurred to a file system between checkpoints. The set of changes can be represented by bitmaps and data structures which may be used by file system check utilities to identify potential errors and to remedy these errors if appropriate. Verifying only file system changes greatly reduces the processing overhead associated with typical backup and recovery mechanisms.

Abstract: A write interface in a file server provides permission management for concurrent access to data blocks of a file, ensures correct use and update of indirect blocks in a tree of the file, preallocates file blocks when the file is extended, solves access conflicts for concurrent reads and writes to the same block, and permits the use of pipelined processors. For example, a write operation includes obtaining a per file allocation mutex (mutually exclusive lock), preallocating a metadata block, releasing the allocation mutex, issuing an asynchronous write request for writing to the file, waiting for the asynchronous write request to complete, obtaining the allocation mutex, committing the preallocated metadata block, and releasing the allocation mutex. Since no locks are held during the writing of data to the on-disk storage and this data write takes the majority of the time, the method enhances concurrency while maintaining data integrity.

Abstract: To avoid the need for storing a tree quota identifier attribute for every file in a quota tree, a tree quota identifier is included in the file handle returned by the file server to a client in response to a directory lookup request. The file server discovers that the file is in a quota tree when searching along a path specified by the file pathname and finding a directory having a tree quota identifier. The file server responds to a client request for changing the storage resources used by the file by inspecting the file handle and upon finding the tree quota identifier in the file handle, using the tree quota identifier to index a tree quota database to find usage and limits for the tree quota. The file server checks the limits against any increase in the storage resources for the file, and updates the usage.

Abstract: Consistency errors may arise during replication of diverse data storage objects from servers in a data network. For preventing consistency errors, a server is programmed for responding to a request for a report of whether or not the server can replicate the dataset without causing a consistency error. Such a report is useful for replicating a consistency group of objects from more than one server. Preparation for replication can be begun at each of the servers, and if any of the servers fail to report that replication can be done without causing a consistency error, the preparation can be aborted so that write access by applications will not be disrupted while the potential problem is diagnosed and eliminated.

Abstract: Technologies are described herein for detecting and managing congestion on a shared network link. A determination is made whether the shared network link is congested based on loss rate and round-trip time (RTT) between a computer and a receiver operatively coupled by the shared network link. Upon determining that the shared network link is congested, a back-off operation is performed on the computer. The back-off operation may reduce an allocated bandwidth of the computer on the shared network link by transforming a higher allocated bandwidth into a lower allocated bandwidth.

Abstract: Architecture employs custom routing tables that facilitate sub-conferences for the main conference session. Sub-conferences in a Voice over IP (VoIP) or Audio/Video over IP (A/VoIP) conference can be created with overlapping sets of sources contributing to overlapping sets of sinks. The custom routing table architecture allows the subdividing of the main routing table into smaller virtual subtables and the configuration of the subtables individually using different corresponding rulesets. These subtables are referred to as groups or conference groups. Each group has a ruleset which defines the routes between sources and sinks of the group. Each source or sink can belong to two or more groups. Thus, the subtables can overlap. Groups and the corresponding rulesets together provide a new way to customize the overall routing configurations in the conference.

Abstract: Read-only and read-write snapshot copies of a production file in a Unix-based file system are organized as a version set of file inodes and shared file blocks. Version pointers and branch pointers link the inodes. Initially the production file can have all its blocks preallocated or it can be a sparse file having only an inode and its last data block. A protocol is provided for creating read-only and read-write snapshots, deleting snapshots, restoring the production file with a specified snapshot, refreshing a specified snapshot, and naming the snapshots. Block pointers are marked with a flag indicating whether or not the pointed-to block is owned by the parent inode. A non-owner marking is inherited by all of the block's descendants. The block ownership controls the copying of indirect blocks when writing to the production file, and also controls deallocation and passing of blocks when deleting a read-only snapshot.

Abstract: Tools and techniques for application-specific heap management are described herein. The tools may provide machine-readable storage media containing machine-readable instructions for profiling an application to facilitate managing heap memory associated with the application, and for managing requests from the application to allocate or deallocate from the heap memory based on the profiling. The tools may also receive requests from the application to allocate buffers, and may determine whether an instance-level memory pool, which is associated with a portion of the application, contains enough free buffers to satisfy the request. Finally, the tools may receive requests from the application to deallocate buffers, and in response to the request, may deallocate the requested buffers into the instance-level memory pool. The tools may also determine whether the instance-level memory pool contains a number of free buffers that exceeds a threshold.