Abstract: Systems, methods, and computer-readable media for static network policy analysis for a network. In one example, a system obtains a logical model based on configuration data stored in a controller on a software-defined network, the logical model including a declarative representation of respective configurations of objects in the software-defined network, the objects including one or more endpoint groups, bridge domains, contexts, or tenants. The system defines rules representing respective conditions of the objects according to a specification corresponding to the software-defined network, and determines whether the respective configuration of each of the objects in the logical model violates one or more of the rules associated with that object. When the respective configuration of an object in the logical model violates one or more of the rules, the system detects an error in the respective configuration associated with that object.

Abstract: Systems, methods, and computer-readable media for performing network assurance in a traditional network. In some examples, a system can collect respective sets of configurations programmed at network devices in a network and, based on the respective sets of configurations, determine a network-wide configuration of the network, the network-wide configuration including virtual local area networks (VLANs), access control lists (ACLs) associated with the VLANs, subnets, and/or a topology. Based on the network-wide configuration of the network, the system can compare the ACLs for each of the VLANs to yield a VLAN consistency check, compare respective configurations of the subnets to yield a subnet consistency check, and perform a topology consistency check based on the topology. Based on the VLAN consistency check, the subnet consistency check, and the topology consistency check, the system can determine whether the respective sets of configurations programmed at the network devices contain a configuration error.

Abstract: Systems, methods, and computer-readable media for identifying conflict rules between models of network intents. A first and second model of network intents are obtained, the models describing the operation and communication between one or more network devices in a network. A logical exclusive disjunction between the first and second models is calculated over the space of possible packet conditions and network actions defined by models, without enumerating all possible packet conditions and network actions. It is detected whether the models are in conflict with respect to at least a first network device. If the models are in conflict, it is determined whether a given rule of a plurality of rules associated with the first model is a conflict rule. The determining comprises calculating the intersection between the given rule and the logical exclusive disjunction, wherein the given rule is a conflict rule if the calculated intersection is non-zero.

Abstract: Systems, methods, and computer-readable media for configuring and verifying compliance requirements in a network.

Abstract: In some examples, a system creates a requirement including EPG selectors representing EPG pairs, a traffic selector, and a communication operator; determines that EPGs in distinct pairs are associated with different network contexts and, for each pair, which network context(s) contains associated policies; creates first data representing the pair, operator, and traffic selector; when only one network context contains the associated policies, creates second data representing a network model portion associated with the only network context and determines whether the first data is contained in the second data to yield a first check; when both network contexts contain the associated policies, also creates third data representing a network model portion associated with a second network context, and determines whether the first data is contained in the second and/or third data to yield a second check; and determines whether policies for the pairs comply with the requirement based on the checks.

Abstract: Systems, methods, and computer-readable media for assurance of rules in a network. An example method can include creating a compliance requirement including a first endpoint group (EPG) selector, a second EPG selector, a traffic selector, and a communication operator, the first and second EPG selectors representing sets of EPGs and the communication operator defining a communication condition for traffic associated with the first and second EPG selectors and the traffic selector. The method can include creating, for each distinct pair of EPGs, a first respective data structure representing the distinct pair of EPGs, the communication operator, and the traffic selector; creating a second respective data structure representing a logical model of the network; determining whether the first respective data structure is contained in the second respective data structure to yield a containment check; and determining whether policies on the network comply with the compliance requirement based on the containment check.

Abstract: Systems, methods, and computer-readable media for performing semantic analysis to identify shadowing events. One or more models of network intents, based at least in part on a priority-ordered listing of rules representing network intents, is received. Each rule comprises a Boolean function of one or more packet characteristics and network fabric conditions, and a corresponding network action. For each given rule of the priority-ordered listing of rules, partial and complete shadowing events are detected based on semantic analysis. The semantic analysis comprises calculating an inverse set that comprises the inverse of the set comprising all rules with a higher or equal priority to the given rule, and then calculating a shadowing parameter that comprises the intersection between the inverse set and the given rule. If the shadowing parameter is equal to zero, a complete shadowing event is detected.

Abstract: Systems, methods, and computer-readable media for identifying conflict rules between models of network intents. A first and second model of network intents are obtained, the models describing the operation and communication between one or more network devices in a network. A logical exclusive disjunction between the first and second models is calculated over the space of possible packet conditions and network actions defined by models, without enumerating all possible packet conditions and network actions. It is detected whether the models are in conflict with respect to at least a first network device. If the models are in conflict, it is determined whether a given rule of a plurality of rules associated with the first model is a conflict rule. The determining comprises calculating the intersection between the given rule and the logical exclusive disjunction, wherein the given rule is a conflict rule if the calculated intersection is non-zero.

Abstract: Systems, methods, and computer-readable media for receiving one or more models of network intents, comprising a plurality of contracts between providers and consumers, each contract containing entries with priority values. Each contract is flattened into a listing of rules and a new priority value is calculated. The listing of rules encodes the implementation of the contract between the providers and the consumers. Each entry is iterated over and added to a listing of entries if it is not already present. For each rule, the one or more entries associated with the contract from which the rule was flattened are identified, and for each given entry a flat rule comprising the combination of the rule and the entry is generated, wherein a flattened priority is calculated based at least in part on the priority value of the given one of given entry and the priority value of the rule.

Abstract: Systems, methods, and computer-readable media for fault code aggregation across application-centric dimensions. In an example embodiment, a system obtains respective fault codes corresponding to one or more network devices in a network and maps the one or more network devices and/or the respective fault codes to respective logical policy entities defined in a logical policy model of the network, to yield fault code mappings. The system aggregates the one or more of the fault code mappings along respective logical policy dimensions in the network to yield an aggregation of fault codes across respective logical policy dimensions and, based on the aggregation, presents, for each of the respective logical policy dimensions, one or more hardware-level errors along the respective logical policy dimension.

Abstract: Systems, methods, and computer-readable media for generating counterexamples for equivalence failures between models of network intents. A listing of conflict rules corresponding to an equivalence failure between at least first and seconds model of networks intents describing the operation and communication of network devices in a network is obtained. A logical exclusive disjunction between first conflict rules from the first model and corresponding second conflict rules from the second model is calculated. One or more counterexamples corresponding to the equivalence failure are generated based at least in part on the logical exclusive disjunction, such that a given counterexample comprises network and packet conditions that cause the first conflict rules to trigger a first action and cause the second conflict rules to trigger a second action that is different from the first action. Hot fields that are more likely to be associated with the equivalence failure are identified in the counterexample.

Abstract: Systems, methods, and computer-readable media for performing semantic analysis to identify shadowing events. One or more models of network intents, based at least in part on a priority-ordered listing of rules representing network intents, is received. Each rule comprises a Boolean function of one or more packet characteristics and network fabric conditions, and a corresponding network action. For each given rule of the priority-ordered listing of rules, partial and complete shadowing events are detected based on semantic analysis. The semantic analysis comprises calculating an inverse set that comprises the inverse of the set comprising all rules with a higher or equal priority to the given rule, and then calculating a shadowing parameter that comprises the intersection between the inverse set and the given rule. If the shadowing parameter is equal to zero, a complete shadowing event is detected.

Abstract: Systems, methods, and computer-readable media for intent specification checks. In one example, a system obtains, from one or more controllers in a software-defined network, a logical model of the software-defined network, the logical model including configurations of one or more objects in a hierarchical management information tree that defines manageable objects and object properties for the software-defined network. Based on the hierarchical management information tree, the system performs a policy analysis of configurations in the logical model and determines, based on the policy analysis, whether the configurations in the logical model contain one or more errors.

Abstract: Systems, methods, and computer-readable media for identifying conflict rules between models of network intents. A first and second model of network intents are obtained, the models describing the operation and communication between one or more network devices in a network. A logical exclusive disjunction between the first and second models is calculated over the space of possible packet conditions and network actions defined by models, without enumerating all possible packet conditions and network actions. It is detected whether the models are in conflict with respect to at least a first network device. If the models are in conflict, it is determined whether a given rule of a plurality of rules associated with the first model is a conflict rule. The determining comprises calculating the intersection between the given rule and the logical exclusive disjunction, wherein the given rule is a conflict rule if the calculated intersection is non-zero.

Abstract: Systems, methods, and computer-readable media for performing network assurance in a traditional network. In some examples, a system can collect respective sets of configurations programmed at network devices in a network and, based on the respective sets of configurations, determine a network-wide configuration of the network, the network-wide configuration including virtual local area networks (VLANs), access control lists (ACLs) associated with the VLANs, subnets, and/or a topology. Based on the network-wide configuration of the network, the system can compare the ACLs for each of the VLANs to yield a VLAN consistency check, compare respective configurations of the subnets to yield a subnet consistency check, and perform a topology consistency check based on the topology. Based on the VLAN consistency check, the subnet consistency check, and the topology consistency check, the system can determine whether the respective sets of configurations programmed at the network devices contain a configuration error.

Abstract: Systems, methods, and computer-readable media for identifying intra-priority class shadowed rules. A network intent model that is based at least in part on a priority-ordered listing of rules representing network intents is received, wherein each rule comprises a Boolean function of one or more packet characteristics and a corresponding network action. Each rule is sorted into a priority class, and for each priority class, it is determined whether each of its constituent rules are intra-priority class shadowed, wherein an intra-priority class shadowed rule can be constructed from the set comprising the remaining rules of the given priority class, and a non intra-priority class shadowed rule cannot be constructed from the set comprising the remaining rules of the given priority class.

Abstract: Systems, methods, and computer-readable media for assurance of quality-of-service configurations in a network. In some examples, a system obtains a logical model of a software-defined network, the logical model including rules specified for the software-defined network, the logical model being based on a schema defining manageable objects and object properties for the software-defined network. The system also obtains, for each node in the software-defined network, a respective hardware model, the respective hardware model including rules rendered at the node based on a respective node-specific representation of the logical model. Based on the logical model and the respective hardware model, the system can perform an equivalency check between the rules in the logical model and the rules in the respective hardware model to determine whether the logical model and the respective hardware model contain configuration inconsistencies.

Abstract: Systems, methods, and computer-readable media for static network policy analysis for a network. In one example, a system obtains a logical model based on configuration data stored in a controller on a software-defined network, the logical model including a declarative representation of respective configurations of objects in the software-defined network, the objects including one or more endpoint groups, bridge domains, contexts, or tenants. The system defines rules representing respective conditions of the objects according to a specification corresponding to the software-defined network, and determines whether the respective configuration of each of the objects in the logical model violates one or more of the rules associated with that object. When the respective configuration of an object in the logical model violates one or more of the rules, the system detects an error in the respective configuration associated with that object.

Abstract: In some examples, a system obtains a network logical model and, for each node in a network, a node-level logical, concrete, and hardware model. The system identifies a service function chain, and determines a respective set of service function chain rules. For each node, the system determines whether the respective set of service function chain rules is correctly captured in the node-level logical model and/or concrete model to yield a node containment check result. Based on a comparison of policy actions in the concrete model, hardware model, and at least one of the node-level logical model or network logical model, the system determines whether the respective set of service function chain rules is correctly rendered on each node to yield a node rendering check result. Based on the node containment check result and node rendering check result, the system determines whether the service function chain is correctly configured.

Abstract: Static random access memory (SRAM) circuits are used in most digital integrated circuits to store data. To handle multiple memory users, an efficient dual port six transistor (6T) SRAM memory cell is proposed. The dual port 6T SRAM cell uses independent word lines and bit lines such that the true side and the false side of the SRAM cell may be accessed independently. Single-ended reads allow the two independent word lines and bit lines to handle two reads in a single cycle using spatial domain multiplexing. Writes can be handled faster that read operations such that two writes can be handled in a single cycle using time division multiplexing. To further improve the operation of the dual port 6T SRAM cell a number of algorithmic techniques are used to improve the operation of the memory system.