An automated analysis system identifies the presence of malicious P-code or N-code programs in a manner that limits the possibility of the malicious code infecting a target computer. The target computer system initializes an analytical virtual P-code engine (AVPE). As initialized, the AVPE comprises software simulating the functionality of a P-code or intermediate language engine as well as machine language facilities simulating the P-code library routines that allow the execution of N-code programs. The AVPE executes a target program so that the target program does not interact with the target computer. The AVPE analyzes the behavior of the target program to identify occurrence of malicious code behavior and to indicate in a behavior pattern the occurrence of malicious code behavior. The AVPE is terminated at the end of the analysis process, thereby removing from the computer system the copy of the target program that was contained within the AVPE.

Computer immune system and method for detecting unwanted code in a P-code or partially compiled native-code program executing within a virtual machine

An analytical virtual machine (AVM) analyzes computer code using a software processor including a register that stores behavior flags indicative of behaviors identified by virtually executing the code within the virtual machine. The AVM includes a sequencer that stores the sequence in which behavior flags are set in the behavior flags register. The AVM analyzes machine performance by emulating execution of the code being analyzed on a fully virtual machine and records the observed behavior. When emulation and analysis are complete, the AVM returns the behavior flags register and sequencer to the real machine and terminates.

Analytical virtual machine

A personal media broadcasting system enables video distribution over a computer network and allows a user to view and control media sources over a computer network from a remote location. A personal broadcaster receives an input from one or more types of media sources, digitizes and compresses the content, and streams the compressed media over a computer network to a media player running on any of a wide range of client devices for viewing the media. The system may allow the user to issue control commands (e.g., “channel up”) from the media player to the broadcaster, causing the source device to execute the commands. The broadcaster and the media player may employ several techniques for buffering, transmitting, and viewing the content to improve the user's experience.

Personal media broadcasting system with output buffer

Aspects of the present disclosure relate to the sharing of synchronization information corresponding to content among devices in a communication network. An originating device collects synchronization information related to the presentation of content to a user via the originating device. The synchronization information is defined according to reference points related to the presentation of the content to the user via the originating device, including a current state of the presentation of the content and/or additional information obtained during the presentation of the content. Based on detection of a synchronization event, the originating device transmits the collected synchronization information, resulting in the receipt of the synchronization information by one or more receiving devices. Thereafter, the presentation of the content to the user on one of the receiving devices can incorporate the synchronization information collected and transmitted by the originating device.

Synchronization of digital content

Providing a user with assurance that a computer is secure based on a vulnerability assessment completed by a browser-compatible scanner operating on the computer. If the scanner finds a vulnerability, the scanner can inform the user that the machine is or may be compromised, or repair the vulnerability. For example, the scanner may be able to repair the vulnerability of the workstation. In the alternative, the scanner can provide the scan results to a network server. If the vulnerability assessment shows that the workstation is compromised, or if the possibility of remote compromise is high, the network server can decline to provide network services to the workstation.

Vulnerability assessment and authentication of a computer by a local scanner

A system and method for synchronizing digital media playback at multiple digital media playback devices interconnected on a network is provided. A digital media playback device comprising a processor, a synchronization component, a timekeeper component and a digital media source performs synchronization processes to arrange for other players to begin playback at a predetermined position and time in the digital media signal. Synchronization is accomplished by processes which approximate the arrival time of a packet containing audio and/or video digital content across the network and instruct the playback devices as to when playback is to begin, and at what point in the streaming media content signal to begin playback. One method uses a time-stamp packet on the network to synchronize all players. Other methods utilize reiterative processes to narrow approximations of packet arrival time at each playback device.

Method and system for synchronization of digital media playback

A method for protecting a computer operating system from unexpected errors write-protects certain critical system components, thereby preventing corruption by application programs, and handles otherwise fatal program errors and infinite loops outside of the context of a malfunctioning program, permitting the program to be reactivated.

System and method for computer operating system protection

A file system for data file storage on a block storage device includes signature information embedded within each block allocated to a data file. Such signature information includes a file identification number, a sequence number within the file, and optional file type information. The signature information is used to reconstruct files on the block storage device in the event of damage to data files or critical system areas on the device. The directory structure for the file system is maintained as a self-contained flat database, stored as a B-tree for expedited searching, including full hierarchical pathnames for each directory entry, thereby enhancing the ability to recover files in a low level of the directory hierarchy when a middle level has been damaged.

Recoverable computer file system with a signature area containing file integrity information located in the storage blocks

A system and method for managing scarce computer system memory resources has three aspects. A first aspect allows large data structures to be replaced by a pointer that causes an intentional fault to occur. The fault is trapped, and the invention interposes the required data. A second aspect associates data structures with both the task and the module that own the structure. The structure can be eliminated from memory when both the owning task and the owning module have terminated. A third aspect utilizes swapping techniques to maintain multiple local data areas for multiple tasks. In conjunctions the three aspects of the invention provide improved resource availability and substantially unimpaired system performance

Computer resource management system

The invention provides a method for reducing the memory requirements and CPU cycle consumption of an executing program in a suspended state suspends the program by intercepting the entry points of the program. The contents of the memory occupied by the program and its data objects are then discarded or compressed, wherein the compressed data is stored at another region in the memory. The memory region containing the uncompressed data is then designated as free memory.

Jonathan A. Daub

Papers

Method and system for synchronization of digital media playback

System and method for computer operating system protection

Recoverable computer file system with a signature area containing file integrity information located in the storage blocks

Computer resource management system

Method for reducing the memory requirements for an application program executing in a multi-tasking environment