Abstract: A method of provisioning a network may include receiving a mapping solution for one or more virtual optical network (VON) requests including virtual nodes and virtual links. The mapping solution may include one mapping pattern for each VON request and each mapping pattern may include an ordered list of physical nodes. The method may also include formulating inequality constraint equations based on physical links that are shared by multiple virtual links. The method may also include formulating range constraint equations for each virtual link based on a physical link for each virtual link with a lowest number of optical transmission slots such that each virtual link occupy a same optical transmission slot across all physical links that are traversed by the virtual link. The inequality and range constraint equations may be solved with satisfiability modulo theories to obtain a slot assignment solution.

Abstract: A method of provisioning an optical network may include receiving one or more virtual optical network (VON) requests. Each VON request may include one or more virtual nodes and one or more virtual links. The virtual nodes may have one or more candidate nodes corresponding to a physical optical network. The method may also include identifying mapping patterns for VON requests by iteratively assigning each virtual node to one of their candidate nodes for each combination of candidate nodes and assigning each virtual link to corresponding physical links. The method may also include formulating a first set of constraint equations based on mapping patterns for the VON requests and formulating a second set of constraint equations based on physical optical network constraints. The first and second set of constraint equations may be solved by satisfiability modulo theories to obtain a mapping solution.

Abstract: According to an aspect of an embodiment, a method may include determining event sequences of an event-driven software application. The method may further include determining, for each event sequence, a distance with respect to each of one or more target conditions of the event-driven software application. The event sequence distance may indicate a degree to which execution of its corresponding event sequence satisfies a corresponding target condition. The method may also include prioritizing execution of the plurality of event sequences based on the event sequence distances. Further, the method may include exploring, according to the prioritization of execution, an event space that includes one or more of the event sequences and a dependent event that corresponds to the one or more target conditions.

Abstract: A method of mapping virtual optical networks (VONs) to a physical network that includes physical links that connect physical nodes. The method includes reading physical network information, VON demands, and technology constraints of the physical network. The method includes determining whether an iteration parameter violates an iterative condition that determines whether to continue processing the VON demands. If not, the method includes determining whether there are unprocessed subgroups of the VON demands. In response to there being unprocessed subgroups, the method includes selecting a subgroup of the VONs. The method includes computing feasible mapping patterns for the subgroup of the VONs. The method includes finding a size of a largest subset of the subgroup that has a feasible mapping and slot assignment solution. The method includes finding a mapping solution of the subset that has a feasible slot assignment and a slot assignment of the mapping solution.

Abstract: A method of mapping virtual optical networks (VONs) to a physical network that includes physical links that connect physical nodes. The method includes reading physical network information, VON demands, and technology constraints of the physical network. The method includes determining whether an iteration parameter violates an iterative condition that determines whether to continue processing the VON demands. If not, the method includes determining whether there are unprocessed subgroups of the VON demands. In response to there being unprocessed subgroups, the method includes selecting a subgroup of the VONs. The method includes computing feasible mapping patterns for the subgroup of the VONs. The method includes finding a size of a largest subset of the subgroup that has a feasible mapping and slot assignment solution. The method includes finding a mapping solution of the subset that has a feasible slot assignment and a slot assignment of the mapping solution.

Abstract: Virtual optical network (VON) provisioning using implicit encoding of mapping constraints may include evaluating mapping choices to exclude certain mapping patterns before evaluating the mapping patterns. For each virtual node in a VON request, candidate physical nodes may be assigned and evaluated for compliance with constraints associated with the VON request. The constraints may be expanded to allow for various selection criteria for the VON request. Multiple VON requests may be simultaneously evaluated to find optimal solutions for the physical network.

Abstract: A satisfiability checking system may include a single instruction, multiple data (SIMD) machine configured to execute multiple threads in parallel. The multiple threads may be divided among multiple blocks. The SIMD machine may be further configured to perform satisfiability checking of a formula including multiple parts. The satisfiability checking may include assigning one or more of the parts to one or more threads of the multiple threads of a first block of the multiple blocks. The satisfiability checking may further include processing the assigned one or more parts in the first block such that first results are calculated based on a first proposition. The satisfiability checking may further include synchronizing the results among the one or more threads of the first block.

Abstract: Methods and systems for symbolic execution of software under test include the use of parametric states to losslessly represent a group of concrete execution states. Mathematical abstractions may represent differences between execution states and may define a parametric constraint for a parametric state. The parametric states may be usable for symbolic execution to reduce an amount of memory resources consumed and/or reduce a computational load during symbolic execution. Using parametric states, a larger state space and more program behaviors may be testable using symbolic execution.

Abstract: In one embodiment, a method may include symbolically executing application code on a first framework. The method may also include creating a first model based on the symbolic execution of the first framework. The method may additionally include symbolically executing the application code on a second framework. The method may further include creating a second model based on the symbolic execution of the first framework. The method may also include determining one or more parameters associated with the first framework based on the first model. The method may additionally include determining one or more parameters associated with the second framework based on the second model. The method may also include selecting one of the first framework and the second framework as a desired framework for execution of the application code based on a comparison of the one or more parameters associated with the first framework and the one or more parameters associated with the second framework.

Abstract: A method of provisioning an optical network may include receiving one or more virtual optical network (VON) requests. Each VON request may include one or more virtual nodes and one or more virtual links. The virtual nodes may have one or more candidate nodes corresponding to a physical optical network. The method may also include identifying mapping patterns for VON requests by iteratively assigning each virtual node to one of their candidate nodes for each combination of candidate nodes and assigning each virtual link to corresponding physical links. The method may also include formulating a first set of constraint equations based on mapping patterns for the VON requests and formulating a second set of constraint equations based on physical optical network constraints. The first and second set of constraint equations may be solved by satisfiability modulo theories to obtain a mapping solution.

Abstract: A method of provisioning a network may include receiving a mapping solution for one or more virtual optical network (VON) requests including virtual nodes and virtual links. The mapping solution may include one mapping pattern for each VON request and each mapping pattern may include an ordered list of physical nodes. The method may also include formulating inequality constraint equations based on physical links that are shared by multiple virtual links. The method may also include formulating range constraint equations for each virtual link based on a physical link for each virtual link with a lowest number of optical transmission slots such that each virtual link occupy a same optical transmission slot across all physical links that are traversed by the virtual link. The inequality and range constraint equations may be solved with satisfiability modulo theories to obtain a slot assignment solution.

Abstract: According to an aspect of an embodiment, a method may include determining event sequences of an event-driven software application. The method may further include determining, for each event sequence, a distance with respect to each of one or more target conditions of the event-driven software application. The event sequence distance may indicate a degree to which execution of its corresponding event sequence satisfies a corresponding target condition. The method may also include prioritizing execution of the plurality of event sequences based on the event sequence distances. Further, the method may include exploring, according to the prioritization of execution, an event space that includes one or more of the event sequences and a dependent event that corresponds to the one or more target conditions.

Abstract: Virtual optical network (VON) provisioning using implicit encoding of mapping constraints may include evaluating mapping choices to exclude certain mapping patterns before evaluating the mapping patterns. For each virtual node in a VON request, candidate physical nodes may be assigned and evaluated for compliance with constraints associated with the VON request. The constraints may be expanded to allow for various selection criteria for the VON request. Multiple VON requests may be simultaneously evaluated to find optimal solutions for the physical network.

Abstract: Systems and methods are disclosed to determine “don't care” variables in programming code. The method comprises obtaining an SMT formula having a plurality of SMT variables from programming code; obtaining a simplified SMT formula from the SMT formula, the simplified SMT formula includes a plurality of simplified SMT variables; obtaining an SAT formula from the simplified SMT formula, the SAT formula includes a plurality of SAT variables; determining which of the plurality of the SMT variables are “don't care” variables from the simplified SMT formula; and determining which of the plurality of the SMT variables are “don't care” variables from the simplified SAT formula.

Abstract: A method may include determining sequence-execution constraints that constrain execution orders of a plurality of events of an event-driven software application. The method may also include determining sequence-position constraints that constrain positions of the plurality of events in one or more possible event sequences of the plurality of events. Further, the method may include determining event-relation constraints that each indicates a relationship between an event input and an event output of each of the plurality of events. Moreover, the method may include forming a constraint set that enumerates the one or more possible event sequences and that includes the sequence-execution constraints, the sequence-position constraints, and the event-relation constraints. In addition, the method may include encoding control flow information of the one or more possible event sequences into the constraint set.

Abstract: Methods and systems for symbolic execution of software under test include the use of parametric states to losslessly represent a group of concrete execution states. Mathematical abstractions may represent differences between execution states and may define a parametric constraint for a parametric state. The parametric states may be usable for symbolic execution to reduce an amount of memory resources consumed and/or reduce a computational load during symbolic execution. Using parametric states, a larger state space and more program behaviors may be testable using symbolic execution.

Abstract: A method of testing software may include generating a symbolic value for a return value of a software function of a software program during mixed symbolic and abstraction execution (“mixed execution”) of the software program. Additionally, the mixed execution may maintain symbolic values, abstract values, and constraints of one or more variables of the software function. The method may also include deriving, during the mixed execution, an abstraction for the symbolic value. The abstraction may constrain the symbolic value and may be derived based on the return value of the paths that satisfy the abstraction. Further, the method may include exploring, during the mixed execution, the one or more paths of the software function that correspond to the return value based on the symbolic value, as constrained by the abstraction, such that a number of the one or more paths explored during the symbolic execution is constrained by the abstraction.

Abstract: A method includes, by one or more computing devices, determining instructions for a computing device to be evaluated, creating a first symbolic test driver including one or more of the instructions to be evaluated and a designation of a symbolic variable corresponding to a portion of the instructions, symbolically executing the instructions with respect to the symbolic variable, determining a test case from the results of the symbolic execution including one or more commands to execute the instructions with a given value for the symbolic variable, determining one or more calls to an object-oriented-programming component in the commands, creating a new symbolic test driver including the calls based on the determined calls, and subsequently symbolically executing the new symbolic test driver.

Abstract: A method includes, by one or more computing devices, determining JavaScript statements to be evaluated, parsing the JavaScript statements, translating the JavaScript statements into Java bytecodes and JavaScript-specific instructions, executing the Java bytecodes in a Java execution engine, calling a JavaScript run-time engine from the Java execution engine, handling one or more semantic operations associated with the JavaScript-specific instructions through use of the JavaScript run-time engine, and providing return values to the Java execution engine. The statements are configured for execution on a computing device. The set of Java bytecodes and JavaScript-specific instructions is configured to conduct symbolic execution of one or more portions of the JavaScript statements. The symbolic execution is configured to evaluate the JavaScript statements.

Abstract: A method of testing software may include accessing first software that includes multiple execution paths and concretely executing the first software using a test case associated with second software to traverse at least a first execution path of the execution paths. The method may also include capturing concrete execution results produced from concretely executing the first software to record the first execution path and symbolically executing the first software using a symbolic input based on the recorded first execution path.