Abstract: Methods of factoring operating system functions into one or more groups of functions are described. Factorization permits operating systems that are not configured to support computing in an object-oriented environment to be used in an object oriented environment. This promotes distributed computing by enabling operating system resources to be instantiated and used across process and machine boundaries. In one embodiment, criteria are defined that govern how functions of an operating system are to be factored into one or more groups. Based on the defined criteria, the functions are factors into groups and groups of functions are then associated with programming objects that have data and methods, wherein the methods correspond to the operating system functions. Applications can call methods on the programming objects either directly or indirectly that, in turn, call operating system functions.

Abstract: A serverless distributed file system manages the storage of files and directories using one or more directory groups. The directories may be managed using Byzantine-fault-tolerant groups, whereas files are managed without using Byzantine-fault-tolerant groups. Additionally, the file system may employ a hierarchical namespace to store files. Furthermore, the directory group may employ a plurality of locks to control access to objects (e.g., files and directories) in each directory.

Abstract: Methods of factoring operating system functions into one or more groups of functions are described. Factorization permits operating systems that are not configured to support computing in an object-oriented environment to be used in an object oriented environment. This promotes distributed computing by enabling operating system resources to be instantiated and used across process and machine boundaries. In one embodiment, criteria are defined that govern how functions of an operating system are to be factored into one or more groups. Based on the defined criteria, the functions are factors into groups and groups of functions are when associated with programming objects that have data and methods, wherein the methods correspond to the operating system functions. Applications can call methods on the programming objects either directly or indirectly that, in turn, call operating system functions.

Abstract: The present invention leverages changes in the sensed strength of radio signals at different locations to determine a device's location. In one instance of the invention, inference procedures are used to process ambient commercial radio signals, to estimate a location or a probability distribution over the locations of a device. In an instance of the invention, learning and inference methods are applied to rank vector of signal strength vectors. Moving to such rank orderings leads to methods that bypass consideration of absolute signal strengths in location calculations. The invention facilitates approximations for locating a device by providing a method that does not require a substantial number of available ambient signal strengths while still providing useful location inferences in determining locations.

Abstract: The present invention employs approximate device locations determined from changes in the sensed strength of radio signals at different locations. In one instance of the invention, the approximate device locations are based on inference procedures that are used to process ambient commercial radio signals, to estimate a location or a probability distribution over the locations of a device. In another instance of the invention, approximate device locations derived from learning and inference methods that are applied to rank vector of signal strength vectors are utilized. Moving to such rank orderings leads to methods that bypass consideration of absolute signal strengths in location calculations. The invention utilizes approximations for a device location that is based on a method that does not require a substantial number of available ambient signal strengths while still providing useful location inferences in determining locations.

Abstract: The present invention leverages changes in the sensed strength of radio signals at different locations to determine a device's location. In one instance of the present invention, inference procedures are used to process ambient commercial radio signals, to estimate a location or a probability distribution over the locations of a device. In another instance of the present invention, a system utilizes learning and inference methods that are applied to rank vector of signal strength vectors. Moving to such rank orderings leads to systems that bypass consideration of absolute signal strengths in location calculations. The present invention facilitates approximations for locating a device by providing a system that does not require a substantial number of available ambient signal strengths while still providing useful location inferences in determining locations.

Abstract: Methods of factoring operating system functions into one or more groups of functions are described. Factorization permits operating systems that are not configured to support computing in an object-oriented environment to be used in an object oriented environment. This promotes distributed computing by enabling operating system resources to be instantiated and used across process and machine boundaries. In one embodiment, criteria are defined that govern how functions of an operating system are to be factored into one or more groups. Based on the defined criteria, the functions are factors into groups and groups of functions are then associated with programming objects that have data and methods, wherein the methods correspond to the operating system functions. Applications can call methods on the programming objects either directly or indirectly that, in turn, call operating system functions.

Abstract: Operating system functions are defined as objects that are collections of data and methods. The objects represent operating system resources. The resource objects can be instantiated and used across process and machine boundaries. Each object has an associated handle that is stored in its private state. When an application requests a resource, it is given a second handle or pseudo handle that corresponds with the handle in the object's private state. The second handle is valid across process and machine boundaries and all access to the object takes place through the second handle. This greatly facilitates remote computing. In preferred embodiments, the objects are COM objects and remote computing is facilitated through the use of Distributed COM (DCOM) techniques. Other embodiments of the invention provide legacy and versioning support by identifying each resource, rather than the overall operating system, with a unique identifier that can specified by an application.

Abstract: A file format for a serverless distributed file system is composed of two parts: a primary data stream and a metadata stream. The data stream contains a file that is divided into multiple blocks. Each block is encrypted using a hash of the block as the encryption key. The metadata stream contains a header, a structure for indexing the encrypted blocks in the primary data stream, and some user information. The indexing structure defines leaf nodes for each of the blocks. Each leaf node consists of an access value used for decryption of the associated block and a verification value used to verify the encrypted block independently of other blocks. In one implementation, the access value is formed by hashing the file block and encrypting the resultant hash value using a randomly generated key. The key is then encrypted using the user's key as the encryption key. The verification value is formed by hashing the associated encrypted block using a one-way hash function.

Abstract: A serverless distributed file system manages the storage of files and directories using one or more directory groups. The directories may be managed using Byzantine-fault-tolerant groups, whereas files are managed without using Byzantine-fault-tolerant groups. Additionally, the file system may employ a hierarchical namespace to store files. Furthermore, the directory group may employ a plurality of locks to control access to objects (e.g., files and directories) in each directory.