Abstract: Hosts or end-systems residing at the edges of a network gather data about the traffic they transmit into and receive from the network. The network's routing protocol (typically a link-state protocol such as OSPF) is monitored and routing data or packets are used to recover the network's current status and topology. This data can be collected, fused, and maintained and a platform, preferably distributed, can be provided to query the data, thus enabling a variety of network management applications.

Abstract: Methods of querying a large number of endsystems are described in which metadata is replicated between endsystems. When a query is injected, an available endsystem receives a message relating to the query which identifies a range of endsystems for which that available endsystem is responsible. The available endsystem then generates completeness data for the range of endsystems based on data stored at the endsystem and this completeness data is transmitted to the sender of the message. The methods may be implemented using device-executable instructions which may be stored on device readable media.

Abstract: A method of optimizing code which invokes methods on a system across an interface is described. High level information relating to the system is accessed and this information is used in performing code transformations in order to optimize the code.

Abstract: An activity model is generated at a computer. The activity model may be generated by monitoring incoming and outgoing data in the computer. The collected data is analyzed to form a graph that describes and predicts what output is generated in response to received input. Later, a window of input and output data is collected from the computer. This collected window of data is used to query the activity model. The graph in the activity model is then used to give the probability that the collected window of data was collected from the computer used to generate the activity model. A high probability indicates that the computer is performing normally, while a low probability indicates that the computer may behaving erratically and there may be a problem with the computer.

Abstract: A method of optimizing code which invokes methods on a system across an interface is described. High level information relating to the system is accessed and this information is used in performing code transformations in order to optimize the code.

Abstract: An activity model is generated at a computer. The activity model may be generated by monitoring incoming and outgoing data in the computer. The collected data is analyzed to form a graph that describes and predicts what output is generated in response to received input. Later, a window of input and output data is collected from the computer. This collected window of data is used to query the activity model. The graph in the activity model is then used to give the probability that the collected window of data was collected from the computer used to generate the activity model. A high probability indicates that the computer is performing normally, while a low probability indicates that the computer may behaving erratically and there may be a problem with the computer.

Abstract: Activity models are maintained on a plurality of computers on a network. When a user or a particular activity model at a computer discovers an error, it may query its own activity model to determine a possible source of the error. If it is determined to not be the likely source of the error, the activity model queries the activity models of those computers on the network that it depends on. These activity models may then query the activity models of the computers that their particular host computer depends on and so forth. Ultimately the results of these activity model queries may be used to diagnose the likely source of the error and may be presented to the requesting user as a report.

Abstract: Methods of querying a large number of endsystems are described in which metadata is replicated between endsystems. When a query is injected, an available endsystem receives a message relating to the query which identifies a range of endsystems for which that available endsystem is responsible. The available endsystem then generates completeness data for the range of endsystems based on data stored at the endsystem and this completeness data is transmitted to the sender of the message. The methods may be implemented using device-executable instructions which may be stored on device readable media.

Abstract: Hosts or end-systems residing at the edges of a network gather data about the traffic they transmit into and receive from the network. The network's routing protocol (typically a link-state protocol such as OSPF) is monitored and routing data or packets are used to recover the network's current status and topology. This data can be collected, fused, and maintained and a platform, preferably distributed, can be provided to query the data, thus enabling a variety of network management applications.