Abstract: Anti jamming system comprising a tunable negative jamming signal feedback loop for feedback suppression of a received jamming signal, including an receiver receiving an jamming signal followed by a replica jamming signal generator for generating an replica jamming signal. The receiver comprising a zero IF PLL receiver having a synchronous demodulator and a phase detector, signal inputs thereof being coupled to said input means and carrier inputs coupled to in-phase and phase quadrature oscillator outputs, respectively, of a local voltage controlled oscillator (VCO), said VCO receiving a tuning control signal for tuning the zero IF PLL receiver at the carrier frequency of the jamming signal. The VCO is included in a phase locked loop (PLL) comprising subsequent to the VCO, said phase detector and a loop filter.

Abstract: Anti jamming system comprising a tunable negative jamming signal feedback loop for feedback suppression of a received jamming signal, including a receiver receiving an jamming signal followed by a jamming signal replica generator for generating an replica jamming signal. The receiver comprising a zero IF PLL jamming signal receiver having a synchronous demodulator and a phase detector, signal inputs thereof being coupled to said input means and carrier inputs coupled to in-phase and phase quadrature oscillator outputs, respectively, of a local voltage controlled oscillator (VCO), said VCO receiving a tuning control signal for tuning the zero IF PLL jamming signal receiver at the carrier frequency of the jamming signal. The VCO is included in a phase locked loop (PLL) comprising subsequent to the VCO, said phase detector and a loop filter.

Abstract: A method and/or system is configured to improve the results of an auto-detection of network devices based on the causes of detection failures in preceding runs of the auto-detection process. As each device that is believed to be in the network is found to be undiscovered, the identification of the device and information regarding the cause(s) of non-discovery are stored. Prior to the next auto-detection run, one or more of the discovery parameters are modified, based on the causes associated with the undiscovered devices. The extent to which the discovery parameters are modified is preferably based on the apparent stability of the network, or upon the detection of changes to the network.

Abstract: Data representing application deployment attributes, network topology, and network performance attributes based on a reduced set of element attributes is utilized to simulate application deployment. The data may be received from a user directly, a program that models a network topology or application behavior, and a wizard that implies the data based on an interview process. The simulation may be based on application deployment attributes including application traffic pattern, application message sizes, network topology, and network performance attributes. The element attributes may be determined from a lookup table of element operating characteristics that may contain element maximum and minimum boundary operating values utilized to interpolate other operating conditions.

Abstract: An interactive virtualization management system provides an assessment of proposed or existing virtualization schemes. A Virtual Technology Overhead Profile (VTOP) is created for each of a variety of configurations of host computer systems and virtualization technologies by measuring the overhead experienced under a variety of conditions. The multi-variate overhead profile corresponding to each target configuration being evaluated is used by the virtualization management system to determine the overhead that is to be expected on the target system, based on the particular set of conditions at the target system. Based on these overhead estimates, and the parameters of the jobs assigned to each virtual machine on each target system, the resultant overall performance of the target system for meeting the performance criteria of each of the jobs in each virtual machine is determined, and over-committed virtual machines and computer systems are identified.

Abstract: Simulation models of media access control and physical layer characteristics facilitate the simulation/emulation of a variety of phenomena that affect transmissions via a wireless media. Such phenomena include media access contention delays, packet drops, and retransmissions that are generally dependent upon changes in transmitter/receiver locations. Each wireless environment is characterized by a model of the communication channel that characterizes transmission effects based on the number of competing transmitters in the environment, which is dynamically determined based on the location of each node in the environment. Additionally, the location of nodes is used to simulate the effects of ‘hidden nodes’, nodes that are unknown to a transmitting node but can interfere with the reception of transmissions at a receiving node. Each device/node model in the wireless environment preferably accesses the same model of the communication channel, thereby minimizing the amount of detail required at each device model.

Abstract: An access discovery method and system discovers and stores the proper access protocol for each device on a network. The discovery process includes progressively sequencing through state transitions until a successful access protocol sequence is determined, and an access script corresponding to this sequence is stored for subsequent access to the device. Preferably, the protocol-discovery algorithm is modeled as a state table that includes a start state and two possible terminal states: success and failure. A state machine executes the state table until a terminal state is reached; if the terminal state is a failure, the system backtracks to attempt an alternative sequence. The process continues until the success state is reached or until all possible sequences are executed without success. An exemplary state model is provided that has been shown to be effective for modeling network devices from a variety of vendor devices.

Abstract: A metric tuning technique optimizes the maximum link utilization of a set of links incrementally. Changes to the metric are constrained to be metric increases to divert routes from select links, thereby minimizing the number of changes required to achieve the optimization by avoiding the potential cascade of changes caused by attracting routes to a link. An interactive user interface is provided to allow a user to specify limits and constraints, and to select the sets of links to be addressed, including, for example, only the links that exceed a given link utilization threshold, the links having the highest link utilizations, the links having the highest failure effect, and so on. This incremental optimization technique is also used to optimize network resiliency by minimizing the network degradation caused by the failure of one or more links.

Abstract: A method for remapping a Media Access Control (MAC) address mapped to a virtual IP address. The method includes examining an activity data file to identify the virtual IP address mapped to the MAC address and remapping the identified MAC address to an IP address. The virtual IP address may be identified utilizing a criteria, such as by determining that the virtual IP address may have two or more mapped MAC addresses. Other criteria may also be suitably employed. A portion of the IP address may be automatically generated. A user may be queried to confirm the generated portion of the IP address. The portion of the IP address may be determined based on prior user entrance of an IP address. The portion of the IP address may be predetermined by a user assigning a naming convention.

Abstract: A user interface to a network simulator facilitates the use of application layer parameters and application layer logic. The user interface is configured to allow the user to define the input in a graphic form, or a text/programming form, or a combination of both. Preferably, the user interface provides common graphic forms for both inputting the data to the simulator as well as for displaying the resultant data from the simulator, thereby easing the progression from the analysis of output from one simulation to the generation of new input for a subsequent simulation.

Abstract: A scalable comparison structure and methodology is provided that is suitable for comparing select data content in hundreds or thousands of files in an efficient manner. Section delimiters are defined to identify the sections of the files within which the select data content is located, and sets of unique sections are identified based on the select data content within the section. Thereafter, comparisons and reports are based on these unique content sections. If multiple files include a common set of data, a single unique content section is used to represent these multiple files. File groups are optionally defined, and different sets of select data content can be compared based on these file groups. The result of the comparison is presented in multiple hierarchical forms, including an identification of which files are different from each other, and an identification of the differences among the unique content segments.

Abstract: The physical connection corresponding to IP tunnels in a network are found by tracing through the device configuration and routing tables at the routers in the network to determine the outbound interface associated with each tunnel endpoint, and then inferring a likely return interface associated with the opposite tunnel endpoint. Having determined the physical devices at the source and destination of each tunnel, the physical path between these source and destination devices is traced from the source toward the destination until the path is terminated at the destination device, or at an interface to an external network. If the path ends at an external network, the path is traced from the destination device toward the source device until a corresponding interface to the external network is reached.

Abstract: The present system includes a system, method and device for inferring connectivity between unconnected network segments. In operation, unconnected network segments are identified. Configuration data related to the unconnected network segments may be examined to facilitate inferring configuration data for an external network connected between the unconnected network segments. The inferred configuration data may be rendered, such as exported or visualized. The inferred configuration data may be related to a communication protocol and/or may be related to network bandwidth. The examined configuration data may be captured directly from one or more of the unconnected network segments and/or may be retrieved from a configuration data file, such as a network configuration model.

Abstract: A spacecraft architecture and accompanying standard allows for the creation of a spacecraft using an assortment of modules that comply with the standard. The standard preferably includes both mechanical and electrical compatibility criteria. To assure physical/mechanical compatibility, the structure of each module is constrained to be compatible with any other compatible module. To minimize the interference among modules, the extent of each module in select dimensions is also constrained. To assure functional compatibility, a common communication format is used to interface with each module, and each public-function module is configured to respond to requests for function capabilities that it can provide to other functions. Each module is preferably designed to provide structural support to the assemblage of modules, and an anchor module is provided or defined for supporting the entire assemblage and coupling the assemblage to other structures, such as a launch vehicle.

Abstract: Network survivability is quantified in such a way that failure cases can be compared and ranked against each other in terms of the severity of their impact on the various performance measures associated with the network. The degradation in network performance caused by each failure is quantified based on user-defined sets of thresholds of degradation severity for each performance measure. Each failure is simulated using a model of the network, and a degradation vector is determined for each simulated failure. A comparison function is defined to map the degradation vectors into an ordered set, and this ordered set is used to create an ordered list of network failures, in order of the network degradation caused by each failure.

Abstract: A simulator simulates routing system protocols to build routing tables corresponding to a modeled network, and a comparator compares the routing tables in the actual network to these simulator-created routing tables. Because the modeled system represents a fault-free version of the actual system, and assuming that the modeled routing system protocols are representative of the algorithms used in the actual routers, these simulator-produced routing tables will represent the ‘ideal’ routing tables that should be present in the routers of the actual network. By querying each router in the actual network for its routing table and comparing each routing table to the corresponding simulator-produced routing table, any differences from the ‘ideal’ can be identified.

Abstract: Systems and methods are disclosed for testing a processor having at least a first interface. In one embodiment, the method includes configuring, at the processor, a second interface, such that the configured second interface has one or more quality of service parameters representative of the first interface; sending one or more packets through the configured second interface, the one or more packets being representative of another packet received at the first interface; and determining, based on the one or more packets, one or more performance parameters corresponding to the first interface under test.

Abstract: Traffic flow between each pair of nodes in a network are determined based on loads measured at each link and based on gravity measures associated with each node. The gravity measures correspond to a relative likelihood of the node being a source or a sink of traffic, and may be assigned based on ‘soft’ characteristics associated with each node, such as the demographics of the region in which the node is located, prior sinking and sourcing statistics, and so on. Because the assigned gravities are relatively subjective, the gravity measures are used to generate an objective function for solving a system of linear equations, rather than as criteria that must be satisfied in the solution. The measured link loads are allocated among the traffic flows between nodes to at least a given allocation efficiency criteria by solving a system of linear equations with an objective of minimizing a difference between the assigned gravities and the resultant gravities corresponding to the determined flows.

Abstract: A network is partitioned into a set of independent partitions, and the topology of each partition is determined, then merged to form a topology of the entire network. Preferably, the partitioning is hierarchical, wherein the network is partitioned to form individual VLAN partitions, and each of the VLAN partitions is further partitioned based on the nodes that are simply connected to each port of one or more selected root switches within the VLAN partition. Simple connections to each port are efficiently determined based on an aggregate address forwarding table associated with each node. Ancillary information, such as spanning tree or CDP data, may be used to facilitate efficient partitioning and/or to validate inferences that are made with incomplete information.

Abstract: A system and method optimizes the information flow regarding node location across a network by controlling the propagation of this information based on distance from the node. Location servers that are near to a node receive detailed information regarding the node's location; location servers that are farther from the node receive less detailed information. In like manner, periodic updates are provided less frequently to distant location servers, and preferably also based on the velocity of a mobile node, or on a priority associated with the mobile node. The location information provided in a message addressed to a node can be minimal when the message is transmitted, and additional detail can be added to this location information by routing nodes as the message is routed closer to its destination, based on information provided by the location servers.