Abstract: Methods and apparatus for data distribution among servers in a grouped server system. Each server in the group includes a device manager which is responsible for brokering devices to services. A service communicates to a device manager on the same server through an inter-process communication mechanism. A desktop unit, having persistent connections with a single device manager, switches to a peer (other device managers in the group) when the desktop unit is reset or when a device manager fails. At least one device is connected to the desktop unit. When the desktop unit is connected to the new device manager, ownership of the devices may change. The new device manager notifies its peers of any device status changes.

Abstract: The present invention provides a method for devices to be remotely accessed over a network. A remote device drive is coupled to a bus device driver at a network client. The remote device driver communicates to a remote bus proxy to a driver service in the server domain. A device manager provides responsibility for discovering services on network clients, enabling driver services to use the devices, notifying other driver services of the availability of devices, notifying clients of the permission to use a device by a service, and tracking connected devices.

Abstract: A pseudo device driver is provided for use by an operation system in a virtual desktop computing environment. The driver has two ports, a master port that is opened by the driver application and a slave port accessed by a program. The two ports provide the functionality necessary for supporting the remote device on the terminal. When a program accesses a device coupled to the terminal, the program opens the pseudo device driver's slave port and proceeds as if the device were coupled to a local bus.

Abstract: A method and apparatus for providing distributed clip-list management. In an embodiment, an application maintains a local clip-list that identifies those portions of a remote frame buffer that are unambiguously associated with the given application, as well as those portions of the remote frame buffer which are disputed between the given application and one or more other applications. Applications may enforce a dispute policy with respect to writing image data to disputed regions of the frame buffer. Applications are able to write to the frame buffer asynchronously, without the use of a frame buffer lock. A clip manager maintains a global clip-list, and responds to messages from the applications by updating the global clip-list and informing those other applications of relevant changes to their own respective local clip-lists.

Abstract: A method and apparatus of supporting an audio protocol in a network environment. Audio processing and hardware requirements associated with a receiver are minimized by specifying a single audio protocol for transmission of audio data between transmitters on a network and the receiver. The protocol specifies a sampling rate, bit resolution and quantization scheme which allow for high sound quality and further minimize the complexity of the receiver. Transmitters are equipped with drivers to provide for conversion of audio data into the designated protocol as needed. Aspects of the designated protocol are provided to compensate for problems associated with transmitting audio streams over a network. The designated protocol specifies a format for interleaving audio samples within data packets to minimize errors which are the result of consecutive missing audio data samples due to packet loss. The receiver may further compensate for missing audio data samples through interpolation.

Abstract: A method and apparatus for adaptably providing data to a virtual desktop system is described. The computational service provider is configured to prepare and transmit one or more data streams through a viable interconnection fabric to multiple HIDs. The data stream is configured by the computational service provider to adaptably meet the performance needs of the HID receiving the data stream. This enables multiple HIDs to receive variants of the same data stream that may differ in quantity, quality, and/or data format. In one embodiment of the invention, a decode module prepares data for transport by separating decoded data into individual processes. Before a HID may connect to a process the HID is authenticated. The processes are further adjusted by a resource optimization module to take into account the characteristics of each HID requesting access.

Abstract: A method and apparatus for adaptably providing data to a virtual desktop system is described. The computational service provider is configured to prepare and transmit one or more data streams through a viable interconnection fabric to multiple HIDs. The data stream is configured by the computational service provider to adaptably meet the performance needs of the HID receiving the data stream. This enables multiple HIDs to receive variants of the same data stream that may differ in quantity, quality, and/or data format. In one embodiment of the invention, a decode module prepares data for transport by separating decoded data into individual processes. Before a HID may connect to a process the HID is authenticated. The processes are further adjusted by a resource optimization module to take into account the characteristics of each HID requesting access.

Abstract: Authentication and session management can be used with a system architecture that partitions functionality between a human interface device (HID) and a computational service provider such as a server. An authentication manager executing on a server interacts with the HID to validate the user when the user connects to the system via the HID. A session manager executing on a server manages services running on computers providing computational services on behalf of the user. The session manager notifies each service in a session that the user is attached to the system using a given HID. A service can direct display output to the HID while the user is attached to the system. When a user detaches from the system, each of the service's executing for the user is notified via the authentication manager and the session manager. Upon notification that the user is detached from the system, a service can continue to execute while stopping its display to the HID.

Abstract: A method and apparatus for controlling the number of users that attempt to concurrently utilize a peripheral device in a network. In a network many users share various peripheral devices such as microphones, cameras, speakers, etc. In one or more embodiments of the invention, to prohibit the concurrent use of a peripheral device by multiple users, a locking mechanism is utilized. The locking mechanism allows a first user that requests access to a peripheral device to maintain an exclusive lock on that device. Once the first user has concluded using the peripheral device, the lock is released to permit another user to access the device. The locking mechanism is controlled by two protocols: the request and the grant protocols. These protocols establish the rules for exclusive access to network peripheral devices using a locking mechanism. A request includes parameters associated with the particular device, and a return address for the requesting terminal or program.

Abstract: The invention provides a method and apparatus for management of communications over media of finite bandwidth. One embodiment of the invention allows management of communications comprising a plurality of data streams from a plurality of sources. One embodiment of the invention effectively quantifies and controls data streams comprising data transferred at either regular or irregular data rates. One embodiment of the invention provides for estimation of data rate needs, measurement and analysis of current and historical data rate parameters, dynamic allocation of available bandwidth, and supports cooperation between data sources and destinations in the management processes.

Abstract: The invention is directed to an error correction scheme used in a computer system where data is provided from a service to a terminal. The data is dynamically changing, and the user is interested more in a final or current state of the data than in intermediate states. Data is provided in a stream of blocks with sequential “sequence” numbers associated with each block. The invention assumes that the data provider transmits data blocks in order of sequence. The terminal tracks the sequence numbers of incoming blocks. When the terminal finds that one or more blocks have been skipped or are missing, the terminal sends a request to the central source for update data. Unlike prior art systems, which request that the missing block or blocks be re-sent, the present invention requests that the information contained in the missing command be provided, for example the current data at the display area associated with the missing block.

Abstract: Authentication and session management can be used with a system architecture that partitions functionality between a human interface device (HID) and a computational service provider such as a server. An authentication manager executing on a server interacts with the HID to validate the user when the user connects to the system via the HID. A session manager executing on a server manages services running on computers providing computational services on behalf of the user. The session manager notifies each service in a session that the user is attached to the system using a given HID. A service can direct display output to the HID while the user is attached to the system. When a user detaches from the system, each of the service's executing for the user is notified via the authentication manager and the session manager. Upon notification that the user is detached from the system, a service can continue to execute while stopping its display to the HID.

Abstract: The present invention is a media interface unit that couples media input (e.g. cameras, microphones) to a network and can receive media input from a network and provide it to playback devices (e.g. monitors, speakers). The interface unit eliminates the need for a computer system when transmitting and receiving media data to and from the internet and other networks. The unit comprises analog audio and video inputs and outputs on one side, and a computer communications network interface on the other side. By coupling sources/sinks of audio/video to one side and by coupling the other side to a network, it is possible to send and receive audio and video data as though the digital communications network were the same as the cables typically used to transport analog audio and video. The invention functions as a multi-media network appliance.