Abstract: A distributed network system includes a distributed server system and a plurality of client devices that are communicatively coupled to the distributed server system. The distributed server system includes multiple servers, each server including a set of client devices registered with the server. Through client re-registration, a client device can move its registration from one server to another server. Through server-side data replication, an object registration request submitted by a client device to a first server is forwarded to a second server without having the client device submitting the same request to the second server.

Abstract: Technologies, systems, and methods for ordered message delivery that avoid message races or crisscrosses between communicating nodes. For example, if Node A sends message 3 towards Node B and, shortly thereafter, Node B sends message X to Node A, Node A would like to know whether or not message X reflects Node B's state after receiving message 3. If Node B received message 3 prior to sending message X, then proper state may be maintained between the nodes. But if messages 3 and X crisscrossed, or if message 3 was never properly received by Node B, then the state between the nodes may be corrupt. Technologies, systems, and methods are provided to avoid such corruption.

Abstract: Clients may subscribe to resources for the purpose of receiving notifications of changes in the resource (e.g., a file is added to a shared folder). Storing subscriptions within persistent storage provides data security in the event of a service failure, at the cost of high latency in accessing subscription data. An efficient method for tracking a resource is provided herein. A subscription service creates subscriptions and monitors resources for a client. Upon a subscribed resource change, a notification service stores a notification of the change into a queue associated with the client. Efficient resource tracking is achieved because notification and subscription data is stored in low latency soft memory. The notification service is configured to detect a failure in the notification service and/or subscription service. In the event a service fails, the client provides a recovery mechanism by resubscribing to resources the client is interested in.

Abstract: Technologies, systems, and methods for ordered message delivery that avoid message races or crisscrosses between communicating nodes. For example, if Node A sends message 3 towards Node B and, shortly thereafter, Node B sends message X to Node A, Node A would like to know whether or not message X reflects Node B's state after receiving message 3. If Node B received message 3 prior to sending message X, then proper state may be maintained between the nodes. But if messages 3 and X crisscrossed, or if message 3 was never properly received by Node B, then the state between the nodes may be corrupt. Technologies, systems, and methods are provided to avoid such corruption.

Abstract: The application discloses a resource assignment system including recovery notification procedures or methods to notify an application or node of potentially lost resources. The recovery notification procedures or calls are invoked in response to a recovery notification registration function. In response to recovery notification registration, a recovery notification or call is generated to report lost resources.

Abstract: Systems and methods for secure file writes after a catastrophic event are allowed over an unauthenticated channel in a serverless distributed file system if an authenticator accompanies the secure file writes. The authenticator can be a power-of-attorney certificate with time limitations, a vector of message authenticated code, or a single message authenticator with secured with a secret shared among members of the serverless distributed file system. The serverless distributed file system includes at least 3f+1 participating computer members, with f representing a number of faults tolerable by the system. The group requires at least one authenticator for file creation and file uploads. Any changes to files stored among the members can be made over an unauthenticated channel if the file changes are secured by the authenticator and the group is able to verify the authenticator.

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 are described for using collaboration of neighboring wireless devices to enable location of disconnected wireless devices and rogue wireless access points. A central server computes the locations of the neighboring clients and uses those locations to estimate the location of a disconnected client. These techniques may take advantage of the beaconing and probing mechanisms of IEEE 802.11 to ensure that connected clients do not pay unnecessary overheads for detecting disconnected clients. Methods are also described for detecting and locating rogue devices by collaboratively collecting information from neighboring devices and comparing the information to a database.

Abstract: An invention is disclosed whereby a wireless network node, equipped with two or more radio transceivers statically tuned to non-interfering frequency channels, can make decisions regarding which channel to use when communicating with a neighboring wireless node. A multi-radio unification protocol implemented in a wireless node coordinates the use of multiple wireless network interface cards and provides a virtual layer that hides the multiple physical network interfaces from higher layers of a node's network protocol stack. The invention is applicable to wireless networks generally, including those in which some nodes do not have multiple radios or do not recognize the multi-radio unification protocol. The invention makes possible simultaneous transmissions using available channels, thereby reducing interference and delay while increasing the overall capacity of the network.

Abstract: Systems and methods are provided to determine execution errors in distributed computing environments. In an illustrative implementation, a computing environment comprises a test amplification engine and at least one instruction set to instruct the test amplification engine to process data representative of a request to perform a test for one or more execution errors in an distributed computing environment according to a selected execution error testing paradigm dependent on identifying critical sources of non-determinism for execution within the exemplary distributed computing environment. In an illustrative operation, a participating distributed computing environment operator (e.g.

Abstract: A file that has been encrypted using a symmetric key and that has a corresponding access control entry with the symmetric key encrypted using the public key of a public/private key pair can be accessed. An encrypted key cache is also accessed to determine whether an access control entry to symmetric key mapping exists in the cache for the access control entry corresponding to the file. If such a mapping exists in the cache, then the mapped-to symmetric key is obtained form the cache, otherwise the encrypted symmetric key is decrypted using the private key of the public/private key pair. The encrypted key cache itself can also be encrypted and stored as an encrypted file.

Abstract: Technologies, systems, and methods for ordered message delivery that avoid message races or crisscrosses between communicating nodes. For example, if Node A sends message 3 towards Node B and, shortly thereafter, Node B sends message X to Node A, Node A would like to know whether or not message X reflects Node B's state after receiving message 3. If Node B received message 3 prior to sending message X, then proper state may be maintained between the nodes. But if messages 3 and X crisscrossed, or if message 3 was never properly received by Node B, then the state between the nodes may be corrupt. Technologies, systems, and methods are provided to avoid such corruption.

Abstract: Technologies, systems, and methods for ordered message delivery that avoid message races or crisscrosses between communicating nodes. For example, if Node A sends message 3 towards Node B and, shortly thereafter, Node B sends message X to Node A, Node A would like to know whether or not message X reflects Node B's state after receiving message 3. If Node B received message 3 prior to sending message X, then proper state may be maintained between the nodes. But if messages 3 and X crisscrossed, or if message 3 was never properly received by Node B, then the state between the nodes may be corrupt. Technologies, systems, and methods are provided to avoid such corruption.

Abstract: The claimed subject matter provides systems and methods that effectuates inter-datacenter resource interchange. The system can include devices that receive a resource request from a client component, forward the resource request to a management component that returns a cluster identity associated with a remote datacenter, the resource request and the cluster identity combined and dispatched to the remote datacenter via an inter-cluster gateway component for subsequent fulfillment by a remote server associated the remote datacenter.

Abstract: Technologies, systems, and methods for ordered message delivery that avoid message races or crisscrosses between communicating nodes. For example, if Node A sends message 3 towards Node B and, shortly thereafter, Node B sends message X to Node A, Node A would like to know whether or not message X reflects Node B's state after receiving message 3. If Node B received message 3 prior to sending message X, then proper state may be maintained between the nodes. But if messages 3 and X crisscrossed, or if message 3 was never properly received by Node B, then the state between the nodes may be corrupt. Technologies, systems, and methods are provided to avoid such corruption.

Abstract: An exclusive encryption system is established using multiple computing devices. The exclusive encryption system allows for the exclusion of certain plaintext (e.g., by one of the computing devices) and ciphertext (e.g., by another of the computing devices) while at the same time maintaining the privacy created by the encryption (e.g., so the other computing device cannot see the plaintext). The exclusive encryption system may be implemented as part of a serverless distributed file system with directory entries (e.g., file names or folder names) being the plaintext, or alternatively as part of other systems.

Abstract: Systems and methods are described for using client conduits to enable bootstrapping and fault diagnosis of disconnected wireless clients. Client conduits are used to enable disconnected clients to diagnose their problems with the help of nearby clients. This technique may take advantage of the beaconing and probing mechanisms of IEEE 802.11 to ensure that connected clients do not pay unnecessary overheads for detecting disconnected clients. Methods are also described for detecting rogue devices disguising as disconnected clients.

Abstract: Clients may subscribe to resources for the purpose of receiving notifications of changes in the resource (e.g., a file is added to a shared folder). Storing subscriptions within persistent storage provides data security in the event of a service failure, at the cost of high latency in accessing subscription data. An efficient method for tracking a resource is provided herein. A subscription service creates subscriptions and monitors resources for a client. Upon a subscribed resource change, a notification service stores a notification of the change into a queue associated with the client. Efficient resource tracking is achieved because notification and subscription data is stored in low latency soft memory. The notification service is configured to detect a failure in the notification service and/or subscription service. In the event a service fails, the client provides a recovery mechanism by resubscribing to resources the client is interested in.

Abstract: An exclusive encryption system is established using multiple computing devices. The exclusive encryption system allows for the exclusion of certain plaintext (e.g., by one of the computing devices) and ciphertext (e.g., by another of the computing devices) while at the same time maintaining the privacy created by the encryption (e.g., so the other computing device cannot see the plaintext). The exclusive encryption system may be implemented as part of a serverless distributed file system with directory entries (e.g., file names or folder names) being the plaintext, or alternatively as part of other systems.

Abstract: A data access architecture is provided that includes a mapping architecture for mapping data as may be used by an application to data as persisted in a database. The mapping architecture makes use of two types of mapping views—a query view that helps in translating queries and an update view that helps in translating updates. Incremental view maintenance can be used to translate data between the application and database.