Patent Publication Number: US-11658872-B1

Title: Business policy management for self-driving network

Description:
This application is a continuation of U.S. patent application Ser. No. 17/385,009, filed 26 Jul. 2021, which is a continuation of U.S. patent application Ser. No. 16/831,607, filed 26 Mar. 2020, which claims the benefit of U.S. Provisional Patent Application No. 62/984,975, filed 4 Mar. 2020 and U.S. Provisional Patent Application No. 62/838,019, filed 24 Apr. 2019, the entire content of each application is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     This disclosure relates to computer networks, and more particularly, to management of network devices. 
     BACKGROUND 
     A computer network is a collection of interconnected computing devices that can exchange data and share resources. A variety of devices operate to facilitate communication between the computing devices. For example, a computer network may include routers, switches, gateways, firewalls, and a variety of other devices to provide and facilitate network communication. 
     These network devices typically include mechanisms, such as management interfaces, for locally or remotely configuring the devices. By interacting with the management interface, a client can perform configuration tasks as well as perform operational commands to collect and view operational data of the managed devices. For example, the clients may configure interface cards of the device, adjust parameters for supported network protocols, specify physical components within the device, modify routing information maintained by a router, access software modules and other resources residing on the device, and perform other configuration tasks. In addition, the clients may allow a user to view current operating parameters, system logs, information related to network connectivity, network activity or other status information from the devices as well as view and react to event information received from the devices. 
     Network configuration services may be performed by multiple distinct devices, such as routers with service cards and/or dedicated service devices. Such services include connectivity services such as layer three virtual private network (L3VPN), virtual private local area network service (VPLS), and peer-to-peer (P2P) services. Other services include network configuration services, such as Dot1q virtual local area network (VLAN) service. Network management systems (NMSs) and NMS devices, also referred to as controllers or controller devices, may support these services such that an administrator can easily create and manage these high-level network configuration services. 
     SUMMARY 
     In general, this disclosure describes techniques for managing network devices. A network management system (NMS) device, also referred to herein as a controller device, may configure business policies, or simply “policies.” In particular, user configuration of devices may be referred to as “intents.” Intents may be represented as intent models, which may be modeled using a data structure, for example, such as, but not limited to, a unified graph model. Intent data models may be represented as connected graphs, so that business policies can be implemented across intent models. For example, data models may be represented using connected graphs having vertices connected with has-edges and reference (ref) edges. Controller devices may model intent models as unified graph models, such that the intend models can be represented as connected. In this manner, business policies can be implemented across intent models. 
     User intents can be categorized as business intents or stateless intents. Business intents, or stateful intents, may be resolved based on the current state of a network. Business intents may include, for example, a data throughput. Stateless intents may be fully declarative ways of describing an intended network/compute/storage state, without concern for a current network state. Stateless intents may include, for example, a virtual private network (VPN) connection between two devices. Application workflows may translate business intents into stateless intents. Controller devices support user intents, such that an administrator can describe the intended state of the network. 
     In customer deployments, there may be thousands to millions of intents. When the intents are changed, the controller device typically deploys data in the network via transactions. In some cases, there may be concurrent changes across the devices, as multiple administrators may modify the intents in parallel. Changes to the intent model may include extending the unified graph model, allowing for extensibility of the intent model. 
     Techniques described herein may help to improve a performance of a network. For example, a controller device may be configured to determine, using an abstract function configured at a node of a plurality of nodes, a stateless intent for implementing a stateful intent. In this example, the controller device may generate low level configuration data for the plurality of network devices based on the stateless intent and interface, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. Determining a stateless intent for implementing a stateful intent for configuring network devices may effectively configure the network devices of the network faster than systems that do not determine a stateless intent for implementing a stateful intent. 
     In one example, a method includes: receiving, by a controller device that manages a plurality of network devices and for a data structure, an indication of a stateful intent, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes; determining, by the controller device, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent; generating, by the controller device, low level configuration data for the plurality of network devices based on the stateless intent; and interfacing, by the controller device, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. 
     In another example, a controller device that manages a plurality of network devices includes one or more processing units implemented in circuitry and configured to: receive, for a data structure, an indication of a stateful intent, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes; determine, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent; generate low level configuration data for the plurality of network devices based on the stateless intent; and interface with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. 
     In one example, a computer-readable storage medium has stored thereon instructions that, when executed, cause a processor of a controller device that manages a plurality of network devices to: receive, for a data structure, an indication of a stateful intent, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes; determine, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent; generate low level configuration data for the plurality of network devices based on the stateless intent; and interface with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. 
     In another example, a controller device that manages a plurality of network devices includes: means for receiving an indication of a stateful intent, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes; means for determining, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent; means for generating low level configuration data for the plurality of network devices based on the stateless intent; and means for interfacing with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. 
     The details of one or more examples are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a block diagram illustrating an example including elements of an enterprise network that are managed using a management device. 
         FIG.  2    is a block diagram illustrating an example set of components for the management device of  FIG.  1   . 
         FIG.  3    is a block diagram illustrating an example workflow to translate business policies into stateless intents. 
         FIG.  4    is a block diagram illustrating an example unified graph model. 
         FIG.  5    is a block diagram illustrating an example process for business intent translation. 
         FIG.  6    is a block diagram illustrating an example business policy analyzer for business intent assurance that may be implemented by the translation module of  FIG.  2   . 
         FIG.  7    is a block diagram illustrating an example graph model of cascaded intents. 
         FIG.  8    is a block diagram illustrating an example business policy analyzer for business intent assurance and conflict detection and correction that may be implemented by the translation module of  FIG.  2   . 
         FIG.  9    is a block diagram illustrating an example graph model for conflict detection. 
         FIG.  10    is a block diagram illustrating an example process for business intent conflict detection and correction for a self-driving network. 
         FIG.  11    is a block diagram illustrating an example business intent state manager that may be implemented by the translation module of  FIG.  2   . 
         FIG.  12    is a block diagram illustrating an example intent state. 
         FIG.  13    is a block diagram illustrating an example of time-based conditions. 
         FIG.  14    is a block diagram illustrating an example of a recurring condition. 
         FIG.  15    is a flowchart illustrating an example process for determining a stateless intent, according to techniques of this disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Techniques described herein may be used in self-driving controllers to support business policies. Some solutions may not provide extensibility of business policies, such as, business intents, and/or may not support end-to-end business policies. Such systems may not support generic modeling to support the business policies that support assurance for the business policies. User intents may include business intents (e.g., stateful intents) that can be resolved into stateless intents based on a current state of a network. Examples of business intents may include, but are not limited to, a bandwidth between devices. Examples of stateless intents may include, but are not limited to, a virtual private network (VPN) connection, a label-switched path (LSP) tunnel, or an optical connection. Stateless intents may include a fully declarative description of the intended network, compute, and/or storage state without a current state of the network. Techniques described herein provide an approach to translate from business intents to stateless intents to configure a network. 
     Rather than configuring network devices with low level configuration data based only on stateless intents (e.g., a VPN connection, an LSP tunnel, etc.), techniques described herein may configure a controller device to determine a stateless intent using a stateful intent (e.g., a desired bandwidth between devices). For example, the controller device may determine a stateless intent for implementing the stateful intent using an abstract function. In this way, the controller device may be extended to support stateful intents, such as business policies. Extending a controller device to support stateful intents may effectively configure the network devices of the network faster than systems that do not determine a stateless intent for implementing a stateful intent. 
       FIG.  1    is a block diagram illustrating an example including elements of an enterprise network  2  that are managed using a controller device  10 . Managed elements  14 A- 14 G (collectively, “elements  14 ”) of an enterprise network  2  include network devices interconnected via communication links to form a communication topology in order to exchange resources and information. Elements  14  (also generally referred to as network devices or remote network devices) may include, for example, routers, switches, gateways, bridges, hubs, servers, firewalls or other intrusion detection systems (IDS) or intrusion prevention systems (IDP), computing devices, computing terminals, printers, other network devices, or a combination of such devices. While described in this disclosure as transmitting, conveying, or otherwise supporting logical packets, enterprise network  2  may transmit data according to any other discrete data unit defined by any other protocol, such as a cell defined by the asynchronous transfer mode (ATM) protocol, or a datagram defined by the user datagram protocol (UDP). Communication links interconnecting elements  14  may be physical links (e.g., optical, copper, and the like), wireless, or any combination thereof. 
     Enterprise network  2  is shown coupled to a public network  18  (e.g., the Internet) via a communication link. Public network  18  may include, for example, one or more client computing devices. Public network  18  may provide access to web servers, application servers, public databases, media servers, end-user devices, and other types of network resource devices and content. 
     Controller device  10  may be communicatively coupled to elements  14  via enterprise network  2 . Controller device  10 , in some examples, forms part of a device management system, although only one device of the device management system is illustrated for purpose of example in  FIG.  1   . Controller device  10  may be coupled either directly or indirectly to the various elements  14 . Once elements  14  are deployed and activated, administrators  12  may use controller device  10  (or multiple such management devices) to manage the network devices using a device management protocol. One example device protocol is the simple network management protocol (SNMP) that allows controller device  10  to traverse and modify management information bases (MIBs) that store configuration data within each of managed elements  14 . Further details of the SNMP protocol can be found in Harrington et al., RFC 3411, “An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks,” Network Working Group, the Internet Engineering Task Force draft, December 2002, available at http://tools.ietf.org/html/rfc3411, the entire contents of which are incorporated herein by reference. 
     Controller device  10 , also referred to as a network management system (NMS) or NMS device, and elements  14  may be centrally maintained by an information technology (IT) group of the enterprise. Administrators  12  may interact with controller device  10  to remotely monitor and configure elements  14 . For example, administrators  12  may receive alerts from controller device  10  regarding any of elements  14 , view configuration data of elements  14 , modify the configurations data of elements  14 , add new network devices to enterprise network  2 , remove existing network devices from enterprise network  2 , or otherwise manipulate the enterprise network  2  and network devices therein. Although described with respect to an enterprise network, the techniques of this disclosure are applicable to other network types, public and private, including local area networks (LANs), virtual LANs (VLANs), VPNs, and other network types. 
     In some examples, administrators  12  uses controller device  10  or a local workstation to interact directly with elements  14 , e.g., through telnet, secure shell (SSH), or other such communication sessions. That is, elements  14  generally provide interfaces for direct interaction, such as command line interfaces (CLIs), web-based interfaces, graphical user interfaces (GUIs), or the like, by which a user can interact with the devices to directly issue text-based commands. For example, these interfaces typically allow a user to interact directly with the device, e.g., through a telnet, secure shell (SSH), hypertext transfer protocol (HTTP), or other network session, to enter text in accordance with a defined syntax to submit commands to the managed element. In some examples, the user initiates an SSH session  15  with one of elements  14 , e.g., element  14 F, using controller device  10 , to directly configure element  14 F. In this manner, a user can provide commands in a format for execution directly to elements  14 . 
     Further, administrators  12  can also create scripts that can be submitted by controller device  10  to any or all of elements  14 . For example, in addition to a CLI interface, elements  14  also provide interfaces for receiving scripts that specify the commands in accordance with a scripting language. In a sense, the scripts may be output by controller device  10  to automatically invoke corresponding remote procedure calls (RPCs) on the managed elements  14 . The scripts may conform to, e.g., extensible markup language (XML) or another data description language. 
     Administrators  12  may use controller device  10  to configure elements  14  to specify certain operational characteristics that further the objectives of administrators  12 . For example, administrators  12  may specify for an element  14  a particular operational policy regarding security, device accessibility, traffic engineering, quality of service (QoS), network address translation (NAT), logical packet filtering, logical packet forwarding, rate limiting, or other policies. Controller device  10  uses one or more network management protocols designed for management of configuration data within managed network elements  14 , such as the SNMP protocol or the network configuration protocol (NETCONF) protocol or a derivative thereof, such as the Juniper™ Device Management Interface, to perform the configuration. In general, NETCONF provides mechanisms for configuring network devices and uses an extensible markup language (XML)-based data encoding for configuration data, which may include policy data. NETCONF is described in Enns, “NETCONF Configuration Protocol,” Network Working Group, RFC 4741, December 2006, available at tools.ietf.org/html/rfc4741. Controller device  10  may establish NETCONF sessions with one or more of elements  14 . 
     Controller device  10  may be configured to compare a new intent model to an existing (or old) intent model, determine differences between the new and existing intent models, and apply the translation functions to the differences between the new and old intent models. In particular, controller device  10  determines whether the new set of configuration data includes any additional configuration parameters relative to the old intent model, as well as whether the new set of configuration data modifies or omits any configuration parameters that were included in the old intent model. 
     The intent model may be expressed in Yang, which is described in Bjorklund, “Yang—A Data Modeling Language for the Network Configuration Protocol (NETCONF),” Internet Engineering Task Force, RFC 6020, October 2010, available at tools.ietf.org/html/rfc6020. In some examples, the intent model may be expressed in JavaScript Object Notation (JSON). Controller device  10  may include various translation functions for translating the intent model differences. These functions are configured accept the intent model (which may be expressed as structured input parameters, e.g., according to Yang or JSON). 
     Controller device  10  may use Yang modeling for intent. This data may contain relations across Yang entities, such as list items and containers. Conventionally, controller devices may not support configuration management functions in real time. As discussed in greater detail below, controller device  10  may convert a Yang data model into a database model and convert Yang validations into data validations. Techniques for managing network devices using a graph model for high level configuration data is described in “CONFIGURING AND MANAGING NETWORK DEVICES USING PROGRAM OVERLAY ON YANG-BASED GRAPH DATABASE,” U.S. patent application Ser. No. 15/462,465, filed Mar. 17, 2017, the entire contents of which are hereby incorporated by reference. 
     The low-level configuration data may conform to a command language supported by each of elements  14 . For instance, low-level configuration data for element  14 A may be in a first vender-specific language supported by element  14 A, low-level configuration data for element  14 B may be in a second vender-specific language supported by element  14 B and not supported by element  14 A, and so on. Controller device  10  may include various reactive mappers for translating the intent data model differences. These functions are configured accept the intent data model (which may be expressed as structured input parameters, e.g., according to YANG or YAML). The functions are also configured to output respective sets of low-level device configuration data changes, e.g., device configuration additions and removals. 
     Controller device  10  may represent an autonomic system that manages itself without human intervention. In some examples, controller device  10  may be configured to perform one or more of self-configuring, self-healing, self-optimizing, or self-protecting. Techniques described herein may take business intents as an input and controller device  10  may be configured to select resources, generate stateless intents corresponding to the business intents, and configure network  2 . 
     In accordance with the techniques of the disclosure, controller device  10  may be configured to translate business intents to stateless intents to configure network  2 . For example, rather than configuring elements  14  with low level configuration data based only on stateless intents (e.g., a VPN connection, an LSP tunnel, etc.), techniques described herein may configure controller device  10  to determine a stateless intent using a stateful intent (e.g., a desired bandwidth between devices). For example, controller device  10  may determine a data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of elements  14  and the plurality of edges defining relationships between the plurality of nodes. In this example, controller device  10  may determine a stateless intent for implementing the stateful intent using an abstract function configured at a node of the plurality of nodes. In this way, controller device  10  may be extended to support stateful intents, such as business policies. Extending controller device  10  to support stateful intents may effectively configure elements  14  of network  2  faster than systems that do not determine a stateless intent for implementing a stateful intent. 
     For example, controller device  10  may represent a controller device configured to perform the method of receiving, for a data structure, an indication of a stateful intent, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes, determining, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent, generating low level configuration data for the plurality of network devices based on the stateless intent, and interfacing, by the controller device, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. 
     In some examples, controller device  10  may represent a controller device configured to perform a method for providing business intent assurance for a self-driving network, the method comprising: generating, a logical packet based on a stateless intent for implementing the stateful intent, injecting the logical packet into a data structure, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes, traversing the logical packet from a source node of the plurality of nodes that is indicated by the stateless intent towards a destination node of the plurality of nodes that is indicated by the stateless intent to generate first low level configuration data for the plurality of network devices, interfacing, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data, collecting aggregated metric information for the plurality of network devices after configuring the one or more of the plurality of network devices with the first low level configuration data, determining the stateless intent is not satisfied based on the aggregated metric information, in response to determining the stateless intent is not satisfied, traversing the logical packet from the source node towards the destination node to generate second low level configuration data for the plurality of network devices, and configuring one or more of the plurality of network devices with the second low level configuration data. 
     In some examples, controller device  10  may represent a controller device configured to perform a method for stateful intent conflict detection comprising: receiving, for a data structure, an indication of a first stateful intent and a second stateful intent, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes, determining, using an abstract function at a node of the data structure, the first stateless intent is in conflict with the second stateless intent, resolving the second stateless intent into a third stateless intent using the abstract function, generating low level configuration data for the plurality of network devices based on the first stateless intent and the third stateless intent, and interfacing, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. 
     In some examples, controller device  10  may represent a controller device configured to perform a method for generating stateless intents, the method comprising: receiving a condition for a policy to operate the plurality of network devices, generating, based on the condition, a stateful intent for a data structure, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes, determining, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent, and interfacing, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices using the stateful intent. 
       FIG.  2    is a block diagram illustrating an example set of components for controller device  10  of  FIG.  1   . In this example, controller device  10  includes a control unit  22 , a network interface  34 , and a user interface  36 . Network interface  34  represents an example interface that can communicatively couple network device  20  to an external device, e.g., one of elements  14  of  FIG.  1   . Network interface  34  may represent a wireless and/or wired interface, e.g., an Ethernet interface or a wireless radio configured to communicate according to a wireless standard, such as one or more of the IEEE 802.11 wireless networking protocols (such as 802.11 a/b/g/n or other such wireless protocols). Controller device  10  may include multiple network interfaces in various examples, although only one network interface is illustrated for purposes of example. 
     Control unit  22  represents any combination of hardware, software, and/or firmware for implementing the functionality attributed to control unit  22  and its constituent modules and elements. When control unit  22  includes software or firmware, control unit  22  further includes any necessary hardware for storing and executing the software or firmware, such as one or more processors or processing units. In general, a processing unit may include one or more microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components. Furthermore, a processing unit is generally implemented using fixed and/or programmable logic circuitry. 
     User interface  36  represents one or more interfaces by which a user, such as administrators  12  ( FIG.  1   ) interacts with controller device  10 , e.g., to provide input and receive output. For example, user interface  36  may represent one or more of a monitor, keyboard, mouse, touchscreen, touchpad, trackpad, speakers, camera, microphone, or the like. Furthermore, although in this example controller device  10  includes a user interface, it should be understood that administrators  12  need not directly interact with controller device  10 , but instead may access controller device  10  remotely, e.g., via network interface  34 . 
     In this example, control unit  22  includes user interface module  38 , network interface module  32 , and management module  24 . Control unit  22  may execute user interface module  38  to receive input from and/or provide output to user interface  36 . Control unit  22  may execute network interface module  32  to send and receive data (e.g., logical packets) via network interface  34 . User interface module  38 , network interface module  32 , and management module  24  may be implemented as respective hardware units, or in software or firmware, or a combination thereof. 
     Functionality of control unit  22  may be implemented as one or more processing units in fixed or programmable digital logic circuitry. Such digital logic circuitry may include one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combination of such components. When implemented as programmable logic circuitry, control unit  22  may further include one or more computer readable storage media storing hardware or firmware instructions to be executed by processing unit(s) of control unit  22 . 
     Control unit  22  may execute management module  24  to manage various network devices, e.g., elements  14  of  FIG.  1   . Management includes, for example, configuring the network devices according to instructions received from a user (e.g., administrators  12  of  FIG.  1   ) and providing the user with the ability to submit instructions to configure the network devices. In this example, management module  24  may include configuration module  26  and translation module  28 . 
     Management module  24  is configured to receive intent unified-graph-modeled configuration data for a set of managed network devices from a user, such as administrators  12 . The intent unified-graph-modeled configuration data may be referred to as an “intent model.” Over time, the user (e.g., administrators  12  of  FIG.  1   ) may update the configuration data, e.g., to add new services, remove existing services, or modify existing services performed by the managed devices. The intent model configuration data may be structured according to, e.g., Yang or JSON. The graph model may include a plurality of vertices connected by edges in a hierarchical fashion. In Yang, edges of graph models are represented though “leafref” elements. In the case of JSON, such edges may be represented with a “ref” edge. Similarly, parent to child vertex relations can be represented with a “has” edge. For example, a vertex for Element A refers to a vertex for Element B using a has-edge can be understood to mean, “Element A has Element B.” In some examples, management module  24  may provide the user with the ability to submit translation functions that translation module  28  executes to transform intent model configuration instructions to device-specific, configuration instructions. 
     Controller device  10  may include configuration database  40 . Configuration database  40  generally includes information describing managed network devices, e.g., elements  14 . For example, configuration database  40  may include information indicating device identifiers (such as a media access control (MAC) address and/or an interne protocol (IP) address), device type, device vendor, devices species (e.g., router, switch, bridge, hub, etc.), and/or other information. Configuration database  40  also stores current configuration information (e.g., intent model configuration information, or in some cases, both intent model configuration) for the managed devices (e.g., elements  14 ). 
     Configuration module  26  may determine an existing set of intent model configuration information for each service performed by the devices for which configuration is to be updated, e.g., by retrieving the existing set of intent model configuration information for each of the services from configuration database  40 . Configuration module  26  may compare the existing set of intent model configuration information to the newly received set of intent model configuration information, and determine differences between the existing and newly received sets of intent model configuration information. Configuration module  26  may pass the differences between the existing and newly received sets of intent model configuration information to translation module  28 , for translation into respective sets of configuration information. Configuration module  26  may update the existing intent model configuration information recorded in configuration database  40  based on the newly received set of intent model configuration information. 
     Translation module  28  may determine which of translation functions  30  to execute on the intent model configuration instructions based on the information of configuration database  40 . Translation module  28  may execute each of the determined translation functions of translation functions  30 , providing the intent model configuration instructions to the translation functions as input and receiving low level configuration instructions. For example, translation module  28  may be configured to generate low level configuration data for network  2  based on stateless intent. In this example, translation module  28  may be configured to interface, with one or more of network elements  14  to configure the one or more of the network elements  14  with the low level configuration data. 
     Some applications may model an intent model as a unified graph model. For instance, in some applications, management module  24  may represent the intent data model as connected, such that business policies can be implemented across intent models. For example, management module  24  may use a data model that is a unified graph, where vertices are connected as with has-edge and ref-edge. In some examples, management module  24  may use an application that includes an intent model as a topology graph. 
     Translation module  28  may be configured to realize business policies to network  2  and provide assurance of the policies. For example, translation module  28  may be configured to determine stateless intents to realize the business policy. Translation module  28  may be configured to select resources for stateless intents. In some instances, translation module  28  may be configured to perform business policy translation based on a network state (e.g., based on endpoints roles, services to be provisioned, etc.). Translation module  28  may configured to perform business intent translation based on current policies running in network  2 . 
     Translation module  28  may represent an autonomic system configured to perform one or more of self-configuring, self-healing, self-optimizing, or self-protecting. Techniques described herein may take business intents as an input and controller device  10  may be configured to select resources, generate stateless intents corresponding to the business intents, and configure network  2 . 
     Techniques described herein represent a complete network represented by a data structure, such as, for example, but not limited to, a unified graph model that includes stateless intents. Such techniques may represent data structure (e.g., the connected unified graph) as a state machine, where the “logical packet” determines the state. As used herein, a logical packet may be configured to traverse nodes of a data structure via one or more edges. The transitions in the model are determined by the logical packet includes location (e.g., vertex id) and “policy functions” in the data structure (e.g., unified graph). Techniques described herein may use policies or business intents as abstract functions that would be attached to vertices of the unified graph. Techniques described herein may construct a logical packet from business intents and transmit the logical packet through abstract functions in the unified graph. The abstract functions may either forward the logical packet to one or more new located logical packets or filter the logical packet. The abstract functions may, for example, be programmed by a human user. Techniques described herein modify the logical packet. As part of modifying the logical packet, techniques described herein may select the resources. This may allow extensibility as, select the resources may allow a controller device to write policies independently. 
     In accordance with the techniques of the disclosure, translation module  28  may be configured to translate business intents to stateless intents to configure network  2 . For example, rather than configuring elements  14  with low level configuration data based only on stateless intents (e.g., a VPN connection, an LSP tunnel, etc.), techniques described herein may configure translation module  28  to determine a stateless intent using a stateful intent (e.g., a desired bandwidth between devices). For example, translation module  28  may determine a data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of elements  14  and the plurality of edges defining relationships between the plurality of nodes. In this example, translation module  28  may determine a stateless intent for implementing the stateful intent using an abstract function configured at a node of the plurality of nodes. In this way, translation module  28  may be extended to support stateful intents, such as business policies. Extending translation module  28  to support stateful intents may effectively configure elements  14  of network  2  faster than systems that do not determine a stateless intent for implementing a stateful intent. 
     For example, controller device  10  may represent a controller device configured to perform the method of receiving, for a data structure, an indication of a stateful intent, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes, determining, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent, generating low level configuration data for the plurality of network devices based on the stateless intent, and interfacing, by the controller device, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. 
       FIG.  3    is a block diagram illustrating an example workflow to translate business policies into stateless intents. In the example of  FIG.  3   , translation module  28  may be configured to receive a business policy (e.g., a business or stateful intent) ( 342 ). Translation module  28  may be configured to translate the business policies to stateless intents ( 344 ) and resources for an element configuration model ( 346 ). For example, translation module  28  may use one or more abstract functions programmed by a human user to translate the business policies to stateless intents, which may be used to translate the resources for an element configuration model. 
     The example workflow of  FIG.  3    may help to determine the stateless intents to realize the business policy. Techniques described herein for determining the stateless intents described herein may include determining a stateless intent based on a current state of network  2  and policies of network  2 . Techniques described herein for determining the stateless intents described herein may include selecting resources for stateless intents. Techniques described herein for determining the stateless intents described herein may support an extension of new business polity models. 
     Controller device  10  may have multiple (e.g., 2, 3, 4, or more than 4) applications. For example, controller device  10  may be configured as a connectivity services controller (e.g., services provider connectivity services -VPNs). Controller device  10  may be configured as a wide area network (WAN) controller (e.g., provision LSPs). Controller device  10  may be configured as a software-drive WAN (SD-WAN) controller (e.g., core to customer network). Controller device  10  may be configured to manage security. 
     For example, after a customer (e.g., an administrator of administrators  12  of  FIG.  1   ) installs a connectivity service controller, when a WAN controller is installed, techniques described herein may extend the business intent model with WAN stateless intents. Moreover, techniques described herein may extend the business intent model with manage security stateless intents. Such techniques may augment business intent translation logic. However, some systems do not provide extensibility of the business policies, do not support end-to-end business policies, and do not support generic modeling to support business policies that supports assurance for business policies. 
       FIG.  4    is a block diagram illustrating an example unified graph model  400 . The example of  FIG.  4    may represent a data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes.  FIG.  4    illustrates an example stateless intent unified graph that includes a VPN intent, a LSP intent, and a Lambda intent. As used herein, Lambda may refer to a photonic switching or wavelength switching. For example, Lambda intent may refer to increasing or decreasing a bandwidth in an optical device. In this example, overall business intents may influence the intent logical packet forwarding (e.g., connectivity), filtering, and modifications. As part of business intent realization, translation module  28  may be configured to create and/or update stateless intents and/or resources for stateless intents. 
     In the example of  FIG.  4   , the business intent of  FIG.  4    is to provide 30 Megabits per second (Mbps) of VPN connectivity between site B (e.g., a source node) and site C (e.g., a destination node). Translation module  28  may be configured to receive a stateful intent for a Layer 3 (L3) VPN (“L3vpn”) and a transport mechanism between site B and site C that provides the 30 Mbps of bandwidth. For example, translation module  28  may traverse a logical packet  402  from site B to site C to provide the business intent of providing 30 Mbps of VPN connectivity between site B and site C. As shown, when logical packet  402  reaches device D2, translation module  28  may apply instructions of abstract function F2 that generate RSVP LSP  414  and VPN  416  between site B and site A and generate a dependent logical packet  404  that traverses RSVP LSP  414  and VPN  416  to device D1, in response to logical packet  402 . When logical packet  404  reaches device D1, translation module  28  may apply instructions of abstract function F1 that generate RSVP LSP  418  and VPN  420  between site A and site C, in response to logical packet  404 . 
     Additionally, when logical packet  402  reaches device D2, translation module  28  may apply instructions of abstract function F3 that generate RSVP LSP  420  and VPN  422  between site B and site C. To generate the stateless optical intent, translation module  28  may be configured to provision a new 10G lambda  424  between cite B and cite C on the optical network. In this way, translation module  28  may be configured to provide 30 Mbps of VPN connectivity between site B and site C without user interaction. While realizing the stateful intents, translation module  28  may be configured to determine existing stateless intents across endpoints and the state. 
     Example properties of logical packet  402  are included in the following table. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 example properties 
               
            
           
           
               
               
               
            
               
                   
                 Field 
                 Description 
               
               
                   
                   
               
               
                   
                 Action 
                 Action of the logical packet. Based on 
               
               
                   
                   
                 business intent, action may be created. 
               
               
                   
                   
                 Allowed values are: 
               
               
                   
                   
                 connect 
               
               
                   
                   
                 Allow 
               
               
                   
                   
                 Block 
               
               
                   
                   
                 . . . 
               
               
                   
                 Source 
                 Source point in the unified intent model. It 
               
               
                   
                   
                 also can contain the selection criteria to pick 
               
               
                   
                   
                 up the source resource. 
               
               
                   
                 Destination 
                 Destination point in the unified intent model. 
               
               
                   
                   
                 It also can contain the selection criteria to pick 
               
               
                   
                   
                 up the destination resource. 
               
               
                   
                 QOS 
                 Quality of the service field. This field would 
               
               
                   
                   
                 be populated based on Action. Applicable in 
               
               
                   
                   
                 case of “Connectivity” action. 
               
               
                   
                 Properties 
                 Json with key, value pairs. Populated by the 
               
               
                   
                   
                 policy functions attached to the vertices in 
               
               
                   
                   
                 Unified Intent model. 
               
               
                   
                   
               
            
           
         
       
     
     A logical packet may be extended based on new policies supported. The properties field may include a key and a value pair that can have additional fields based on new policies. 
     Translation module  28  may be configured to use resource roles through labels. For example, translation module  28  may use a unified graph model that includes a stateless intent applied on network elements such as devices, interfaces, and other network elements. In some examples, the unified graph model may include a role for every network element. For instance, the unified graph model may include roles such as, but not limited to, a core device, an edge device, a hub device, and other roles. 
     Translation module  28  may be configured for action to intent mapping. For example, translation module  28  may be configured to use overall business intents to influence intent logical packet forwarding (e.g., connectivity), filtering, modifications. In some examples, action to intent mapping may be signified with an action field in a simulated logical packet. The action to intent mapping may be maintained in translation module  28  for a given action and/or intent based on a role. For example, to support connectivity, translation module  28  may be configured to use action to intent mapping with Layer-2 VPN services (12vpn) and/or Ethernet VPN (EVPN). In this example, translation module  28  may use action to intent mapping EVPN for core devices as illustrated in the following table, which may be customized based on a customer environment. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Example Action to Intent Mapping 
               
            
           
           
               
               
               
               
            
               
                   
                 Action 
                 Role 
                 Intent 
               
               
                   
                   
               
               
                   
                 Connectivity 
                 Datacenter edge 
                 EVPN 
               
               
                   
                   
                 Edge 
                 L3VPN 
               
               
                   
                   
                 L2 Network 
                 VLAN 
               
               
                   
                 Allow 
                 Edge 
                 Firewall 
               
               
                   
                 Modify 
                 Edge 
                 NAT 
               
               
                   
                   
               
            
           
         
       
     
     For example, in response receiving a connectivity action of logical packet  402  and a label for device D2 indicating that device D2 is a datacenter edge, translation module  28  may be configured to apply Table 2 to map an intent of connectivity action to an EVPN. 
       FIG.  5    is a block diagram illustrating an example process for business intent translation. In the example of  FIG.  5   , a user may add or update a business policy ( 502 ). For example, a user (e.g., an administrator of administrators  12  of  FIG.  1   ) may provide an input indicating a business intent of providing 30 Mbps of VPN connectivity between site B and site C of  FIG.  4   . When the business intent is received by translation module  28 , translation module  28  may be configured to create a logical packet based on the business intent ( 504 ) and inject the logical packet to the source node of the connected graph ( 506 ). For example, translation module  28  may generate logical packet  402  and inject the logical packet to device D2. There may be labels for the network elements. For example, device D2 may have a label of “datacenter edge.” Based on an action of the logical packet, translation module  28  may be configured to pick the corresponding policy using a role ( 508 ). For example, translation module  28  may be configured to select EVPN using Table 2 in response to determining D2 has a label of “datacenter edge” and logical packet  402  indicating an action of “connectivity.” There may be many ways to achieve business intent. To support connectivity, translation module  28  may be configured to use 12vpn/EVPN. But for core devices, translation module  28  may be configured to use EVPN. 
     Once the policy is picked, translation module  28  may be configured to trigger the business function attached to the intent ( 510 ). For example, translation module  28  may be configured to pass the logical packet through the EVPN abstract function F2 and/or F3. Translation module  28  may be configured to identify intent values based on the logical packet content ( 512 ). For example, translation module may perform a function that checks the bandwidth parameter and identifies the EVPN policy object to achieve the business intent. 
     Translation module  28  may be configured to get (e.g., receive, determine, etc.) newly located logical packets ( 518 ) and output the logical packet that would be located to the next endpoint. Translation module  28  may be configured to check if there is any dependent intent ( 514 ) and update the logical packet action ( 546 ) and inject. For example, translation module  28  may be configured to generate logical packet  404  and output logical packet  404  to device D1 according to instructions of EVPN abstract function F2 and logical packet  402 . After steps  516  and  518 , the process of  FIG.  5    will proceed to step  506 . For instance, translation module  28  may be configured to determine a dependent packet using the abstract function and the packet and inject the dependent packet towards a next node of a data structure. 
     The following changes may support new use cases. In some examples, translation module  28  may be configured to use stateless intent models. Translation module  28  may be configured to use business policy functions. Translation module  28  may be configured to extend a logical packet with actions. In this way, translation module  28  may be configured to support business intents without modifying the existing business intent translation logic. 
     Techniques described herein may provide one or more of the following. Translation module  28  may be configured to determine the stateless intents to realize the business policy. For example, translation module  28  may be configured to determine the stateless intents based on the current state of the network and policies in network  2 . Translation module  28  may be configured to select the resources for the stateless intents. In some examples, translation module  28  may be configured to support extension of new business policy models. 
     The techniques described herein may be used in SDN controllers, orchestration systems, network management systems, or other systems. Such techniques may help to solve business policy support. 
       FIG.  6    is a block diagram illustrating an example business policy analyzer for business intent assurance that may be implemented by translation module  28  of  FIG.  2   . Techniques described herein may be used in self-driving controllers to support business policies. Some solutions may not provide extensibility of the business policies. Some solutions do not support end-to-end business policies. Moreover, in some systems there is no generic modeling to support business policies that supports assurance for the business policies. 
     Based on business intent realization, translation module  28  may be configured to derive network modeling. Translation module  28  may be configured to register for resource monitoring for the selected resources from analytics module. In the example of  FIG.  6   , translation module  28  may include a business policy module  601 , a stateless intent module  603 , and an analytics node  605 . 
     Business policy module  601  may be configured to generate unified graph  606  and to inject logical packets into unified graph  606  for business intent assurance. As shown, business policy module  601  may include business policy analyzer  602  and assurance module  604 . Business policy analyzer  602  may be configured to inject logical packets into unified graph  606  to generate a stateless intent from a business intent. Assurance module  604  may be configured to inject logical packets into unified graph  606  to recreate a logical packet to ensure that the business intent is satisfied even in cases of cascaded intents or a degradation of network  2 . 
     Stateless intent module  603  may be configured to translate one or more stateless intents into element configuration information. Intent layer  608  may be configured to receive stateless intents from business policy analyzer  602 . For example, business policy analyzer  602  may determine a business policy based on input by a human user, generate one or more stateless intents for the business policy, and output the one or more stateless intents to intent layer  608 . Intent translator  612  may be configured to translate from one or more stateless intents into element configuration information. Element configuration service  614  may be configured to push the element configuration information to devices (e.g., elements of network  2 ) using intent database  610  and/or configuration database  616 . Configuration database  616  may store element configuration element. For example, intent database  610  may include one or more preprogrammed abstraction functions (e.g., F1, F2, F3, etc.). In this example, intent translator  612  may generate the one or more stateless intents using the process described in  FIG.  5   . 
     Analytics node  605  generates analytical information for assurance module  604 . As shown, analytics node  605  may include telemetry aggregation  620 , element telemetry collection  622 , and telemetry database  624 . Telemetry aggregation  620  may aggregate analytic information stored in telemetry database  624  to determine whether a business intent is satisfied after applying configuration information to elements of network  2 . For example, telemetry aggregation  620  may be configured to determine aggregated metric information. In this example, telemetry aggregation  620  may be configured to determine whether network  2  provides a bandwidth between site A and site B that is specified by a business policy. 
     Telemetry collection  622  may be configured to generate telemetry information for individual elements (e.g., elements  14 ) of network  2 . 
     In the example of  FIG.  6   , assurance module  604  may inject a logical packet previously injected by business policy analyzer  602  when analytics node  605  generates analytical information (e.g., aggregated metric information) indicating a resource degraded event has occurred. For example, while a business policy may specify a bandwidth of  30  Mbps between site A and site B, degradation at one or more of elements  14  may provide a bandwidth of only 15 Mbps. In this example, analytics node  605  would output an indication to assurance module  604  that a degradation event has occurred and assurance module  604  may inject a logical packet specifying a bandwidth of 30 Mbps between site A and site B. 
     Telemetry aggregation  620  may be configured to determine telemetry information at two or more of network elements  14 , store the telemetry information at telemetry database  624 , and generate the aggravated telemetry information using the telemetry information stored at telemetry database  624 . 
     In this way, assurance module  604  would cause stateless intent module  603  to configure elements  14  to provide the bandwidth of 30 Mbps between site A and site B to provide business policy assurance. Techniques for business intent assurance may permit auto generation of assurance logic for business intents. Such techniques may provide an approach for the assurance for the multi layered intents. Translation module  28  may be configured to support extension for the new business policy models. 
     In some examples, translation module  28  of  FIG.  6    may represent a controller device configured to perform a method for providing business intent assurance for a self-driving network, the method comprising: generating, a logical packet based on a stateless intent for implementing the stateful intent, injecting the logical packet into a data structure, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes, traversing the logical packet from a source node of the plurality of nodes that is indicated by the stateless intent towards a destination node of the plurality of nodes that is indicated by the stateless intent to generate first low level configuration data for the plurality of network devices, interfacing, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data, collecting aggregated metric information for the plurality of network devices after configuring the one or more of the plurality of network devices with the first low level configuration data, determining the stateless intent is not satisfied based on the aggregated metric information, in response to determining the stateless intent is not satisfied, traversing the logical packet from the source node towards the destination node to generate second low level configuration data for the plurality of network devices, and configuring one or more of the plurality of network devices with the second low level configuration data. While the example of  FIG.  6    generates a unified graph, translation module  28  may be configured to generate other types of data structures. 
       FIG.  7    is a block diagram illustrating an example graph model of connectivity intents. In case of cascaded intents, translation module  28  may be configured to apply business intent assurance across layers. For connectivity intents, translation module  28  may be configured to apply business intent assurance as shown in  FIG.  7   . While the example of  FIG.  7    shows a unified graph, translation module  28  may be configured to generate other types of data structures. 
     In the example of  FIG.  7   , element telemetry collection  622  generates metrics  742  for VPN  702 , metrics  744  for LSP 2  704 , and metrics  746  for Lambda  706  which are stored at telemetry database  624 . Telemetry aggregation  620  generates aggregated metrics  740  using metrics  742 , metrics  744 , and metrics  746 . As shown, aggregated metrics  740  indicates that Border Gateway Protocol (BGP) count is less than 1000 minimum latency. In this way, translation module  28  may be configured to derive the network modeling across layers. The various layer for the given example are: D2-VPN-D3, D2-LSP-D3, and D2-optical-Lamda-Optical2-lambda-D3. Any combination of metrics  740 - 746  may represent examples of aggregated metric information. 
     When the resource degraded event comes from analytics node  605 , assurance module  604  may be configured to derive the impacted paths in unified graph  606 . Assurance module  604  may be configured recreate the logical packet and select the resources and call various stateless intents. 
     Assurance module  604  may be configured to perform resource selection. Resource selection may be considered an optimization problem, where a business policy analyzer may select optimized resources based on logical packet query. For example, assurance module  604  may be configured to derive decision variables, objectives, constraints, or other information. 
     Assurance module  604  may be configured with an interface with analytics module  605 . In this way, assurance module  604  may be configured to enable monitoring for properties on resources, listen for the metrics from analytics node  605 , configure events on analytics node  605  for thresholds, and/or listen for the threshold crossing events and run stateless intent module  603 . 
     Techniques described herein may allow for an approach to assurance for the business intents, auto generation of the assurance logic for business intents, provide an approach for the assurance for the multi layered intents. In some examples, translation module  28  may be configured to support extension for the new business policy models. Techniques described herein for business intent assurance may be used in SDN controllers, orchestration systems, network management systems, and/or other systems. In this way, techniques described herein for business intent assurance may help to provide business policy support. 
       FIG.  8    is a block diagram illustrating an example business policy analyzer for business intent assurance and conflict detection and correction that may be implemented by the translation module of  FIG.  2   . In the example of  FIG.  8   , translation module  28  includes a stateless intent module  603  and an analytics node  605  as described in  FIG.  6   . Similar to business policy module  601 , business policy module  801  includes unified graph  606  and assurance module  604 . 
     However, business policy module  801  includes business policy analyzer and conflicts detection and correction  802  (or simply “analyzer with conflict correction  802 ”). Similar to business policy analyzer  602 , analyzer with conflict correction  802  may be configured to inject logical packets into unified graph  606  to generate a stateless intent from a business intent. Moreover, analyzer with conflict correction  802  may be configured to detect the conflict and resolve a conflict as part of realization when new a business intent is being realized. For example, analyzer with conflict correction  802  may be configured to determine, using an abstract function at a node of a data structure, a first stateless intent is in conflict with the second stateless intent. In this example, analyzer with conflict correction  802  may be configured to resolve the second stateless intent into a third stateless intent using the abstract function. The abstract functions may, for example, be programmed by a human user. 
     Analyzer with conflict correction  802  may generate a mapping from affected network elements of network elements  2  to the impacted business intents and provide remediation. In some examples, translation module  28  of  FIG.  8    may represent a controller device configured to perform a method for stateful intent conflict detection comprising: receiving, for a data structure, an indication of a first stateful intent and a second stateful intent, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes, determining, using an abstract function at a node of the data structure, the first stateless intent is in conflict with the second stateless intent, resolving the second stateless intent into a third stateless intent using the abstract function, generating low level configuration data for the plurality of network devices based on the first stateless intent and the third stateless intent, and interfacing, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data. 
       FIG.  9    is a block diagram illustrating an example graph model for conflict detection. As shown, the graph model of  FIG.  9    may include paths across vertices along with actions and properties. The actions may include connect, allow, block, modify, and other actions. 
     In the example of  FIG.  9   , analyzer with conflict correction  802  injects a logical packet  902  to Customer-Premise Equipment (CPE)  912  with a first business intent. In this example, the first business intent of logical packet  902  includes an action to allow a file transfer protocol (FTP) connection from department 1  914  (“DEP1”) to department 2  916  (“DEP2”), the corresponding network model is “Network model : CPE1-Allow {protocol: FTP , endpoints:*}” 
     In this example, logical packet  902  further includes a second business intent, which includes an action to allow FTP from Department 1  912  to Department 2  914  for Address1, the corresponding network mode may be “Network model : CPE1-Allow {protocol: FTP , endpoints:Address1}.” Moreover, logical packet  902  further includes a third business intent, which includes an action to apply static NAT for Adress1 in Site A  916 , the corresponding network mode may be “Network model : CPE1-Modify {from: Address1, to : Address 2}.” 
     In the example of  FIG.  9   , analyzer with conflict correction  802  applies the second business intent, the network model will be:CPE1-Allow { protocol: FTP, endpoints:Address1}. After applying the second business intent, analyzer with conflict correction  802  applies the third business intent. In this example, abstract function  920  takes logical packet  902  for applying a static NAT from the third business intent and checks if logical packet  902  is impacting any network flow. In this case, the third business intent of logical packet  902  conflicts with the second business intent of logical packet  902 . As such, analyzer with conflict correction  802  may modify the second business intent corresponding firewall (FW) policy and the output may be to forward a policy with updated rule and output a NAT policy. 
     Analyzer with conflict correction  802  may be configured to get the action from logical packet  902  using function  920 . If the action from logical packet  902  is to modify, analyzer with conflict correction  802  may check if the unified model  900  is impacted, get the business intent impacted with the current business intent, and call a resolve module with the logical packet and network model. If a user input is used to resolve, analyzer with conflict correction  802  may return the conflicted business intents and solution. 
     Analyzer with conflict correction  802  may be configured to perform a conflict resolve algorithm as follows. Analyzer with conflict correction  802  may get a logical packet and conflicted network model. If the conflict is resolved, by updating the conflicted network model, analyzer with conflict correction  802  may update the policy. If analyzer with conflict correction  802  is not able to resolve the conflict, analyzer with conflict correction  802  may generate the suggested solutions in terms of logical packet and generate the updated business intents and show to a user. For example, analyzer with conflict correction  802  may be configured to output a notification indicating an unresolved conflict has occurred in response to determining, using the abstract function, the stateless intent is in conflict with another stateless intent and cannot be resolved. 
       FIG.  10    is a block diagram illustrating an example process for business intent conflict detection and correction for a self-driving network. In some examples, analyzer with conflict correction  802  may be configured to detect conflicts across business intents in translation and correct conflicts. In this way, analyzer with conflict correction  802  may be configured to detect the conflicts across business intents. When the intents are conflicting, analyzer with conflict correction  802  may be configured to automatically resolve the conflict and provide solution. Analyzer with conflict correction  802  may be configured to support an extension for the business policy models. 
     Techniques for business intent conflict detection and correction may be used in self-driving controllers to support business policies. Some solutions do not provide extensibility of the business policies. Some solutions do not support conflicts detection handling, if the end point groups are not overlapping. Some solutions do not provide the auto correction. The challenge with some solutions is the performance. There can be thousands of business intents across hierarchal groups. In such systems, the system may check all the intents which can be conflicting, as the analysis need to be done across all intents. 
     When the business intent is realized, analyzer with conflict correction  802  may be configured to build a network model. Business functions may be attached to the vertices aware of the existing model. When new business intent is being realized, analyzer with conflict correction  802  may detect the conflict and resolve the conflict as part of realization. 
     As shown in  FIG.  10   , analyzer with conflict correction  802  may receive a user submission of business intent changes ( 1002 ). Analyzer with conflict correction  802  may construct a logical packet and inject the logical packet to a graph ( 1004 ). Analyzer with conflict correction  802  may apply an abstract function (e.g. F1, F2, F3, etc.) that determines if a conflict with the network model exists ( 1006 ). In response to no conflict (“No” of step  1006 ), analyzer with conflict correction  802  computes an updated policy ( 1010 ). 
     In response, however, to a conflict, analyzer with conflict correction  802  determines whether the conflict can be resolved ( 1008 ). In response to determining that the conflict may be resolved (“Yes” of step  808 ), analyzer with conflict correction  802  resolves the conflict and computes an updated policy ( 1010 ). In response, however, to determining that the conflict may be not resolved (“No” of step  1008 ), analyzer with conflict correction  802  gets the conflicted policy, generates a recommendation, and notifies an application on failure ( 1012 ). 
       FIG.  10    illustrates an approach to detect the conflicts across business intents. When the intents are conflicting, analyzer with conflict correction  802  may automatically resolve the conflict and provide the solution. Analyzer with conflict correction  802  may support extension for the new business policy models. Such techniques for detecting conflicts may be used in all SDN controllers, orchestration systems, network management systems, or other systems. This may help to provide business policy support. 
     Some solutions do not provide generic state management for the policies. Such systems may suffer from state explosion. For example, as the business intent results in many endpoints, the state may be maintained for every endpoint. Some solutions allow a developer to define groups that make all the endpoints belong to same group would be part of same state. This may not work in all scenarios, where every element in business policy lead to its unique state. 
       FIG.  11    is a block diagram illustrating an example process for business intent state management. In the example of  FIG.  11   , translation module  28  includes stateless intent module  603  and analytics node  605  as described in  FIG.  6   . Similar to business policy module  801 , business policy module  1101  includes analyzer with conflict correction  802 , unified graph  606 , and assurance module  604 . However, business policy module  1101  further includes business intent state machine  1120 . 
     Business intent state machine  1120  may be configured to work with analytics node  605  to run state management. For example, rather than individually programing a business intent between each endpoints of network  2 , a human user may program a single intent specifying a condition and business intent state machine  1120  automatically generates a business intent between each endpoints of network  2  in response to events from analytics node  605 . For instance, business intent state machine  1120  may check if there is a state that exists in any of the models with same endpoint group, derive a state and/or a policy from the model, and add the transition events between states. In this way, techniques for business intent state management may allow the plug ability of business intents, allow an approach to generate the states from business intent model, and allow an approach to manage the state for the business polices without “state explosion.” Such techniques may be used in SDN controllers, orchestration systems, network management systems, or other systems. This may help to solve business policy support. 
     For example, business intent state machine  1120  may be configured to generate, based on the condition, a stateful intent for a data structure. In some examples, the condition is a time-based condition. For instance, business intent state machine  1120  may be configured to determine the time-based condition is satisfied and generate the stateful intent in response to determining the time-based condition is satisfied. In some examples, the condition is a recurring condition. For instance, business intent state machine  1120  may be configured to determine the recurring condition is satisfied and generate the stateful intent in response to determining the time-based condition is satisfied. 
     Business intent state machine  1120  may allow translation module  28  to manage the state of the business intent based on a model. Business intent state machine  1120  may determine the state trigger based on (a) conditions recurring or scheduled or (b) an event in network  2 . Business intent state machine  1120  may automatically update the state model based on the business policy model. Business intent state machine  1120  may support extensibility of the business intents. Business intent state machine  1120  may register for event changes to an analytics module for events. In this way, business intent state machine  1120  may allow plug ability of the business intents. Techniques for business intent state management may generate the states from business intent model and provide an approach to manage the state for the business polices without “state explosion.” As such, the techniques may be used in self-driving controllers to support business policies. 
     In some examples, translation module  28  of  FIG.  11    may represent a controller device configured to perform a method for generating stateless intents, the method comprising: receiving a condition for a policy to operate the plurality of network devices, generating, based on the condition, a stateful intent for a data structure, the data structure including a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of the plurality of network devices and the plurality of edges defining relationships between the plurality of nodes, determining, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent, and interfacing, with one or more of the plurality of network devices to configure the one or more of the plurality of network devices using the stateful intent. 
       FIG.  12    is a block diagram illustrating an example intent state. For example, intent  1202  may include subject  1204 , action  1206 , constraint  1208 , and condition  1210 . Subject  1204  may include end point group  1212 . Action  1206  may include block  1214  and allow  1216 . Constraint  1208  may include exclude  1218  and include  1220 . Condition  1210  may include condition types recurring  1222  and scheduled  1224 . Business intents may include the conditions. The conditions may be time based scheduled or recurring. 
       FIG.  13    is a block diagram illustrating an example of a time-based condition. In the example of  FIG.  13   , first state  1302  is when there is no match with no policy and second state  1304  is when there is a match with a policy to connect between site A and site B. For example, business intent state machine  1120  may generate a business intent specifying 10 Mbps connecting site A and site B when analytics node  605  determines an event specified by a human user for the business intent is satisfied (e.g., the timer is between 9 AM to 6PM). In this example, analyzer with conflict correction  802  may inject a logical packet indicating the business intent specified by business intent state machine  1120  to allow management of the state of network  2  for business polices without “state explosion.” 
       FIG.  14    is a block diagram illustrating an example of a recurring condition. Business intents can include the conditions based on events. In the example of  FIG.  14   , first state  1402  is when not infected with a policy of allow and second state  1404  is when infected with a policy of drop. For example, business intent state machine  1120  may generate a business intent to drop logical packets when an event specified by a human user for the business intent is satisfied (e.g., a department is infected). Business intent state machine  1120  may expand the state diagram when new intent models are defined. For example, when infected, but the address is from a first office, business intent state machine  1120  may have dedicated policy. In this example, business intent state machine  1120  may cause analyzer with conflict correction  802  to inject a logical packet indicating the business intent specified by business intent state machine  1120  to allow management of the state of network  2  for business polices without “state explosion.” 
     In some examples, business intent state machine  1120  may include an interface with analytics node  605  to enable the monitoring for the required properties on resources, to configure the events on analytics node  605  for thresholds, and to listen for the threshold crossing events and run the state management. In this way, translation module  28  may address state explosion such that there can many endpoints resolved from the business intent, every endpoint can result its own state, and a system should maintain one record for every state. A group may have a reference to one among the state and a violated endpoint may be referring to a state of the endpoint. 
       FIG.  15    is a flowchart illustrating an example process for determining a stateless intent for implementing the stateful intent, according to techniques of this disclosure.  FIG.  15    is discussed with respect to  FIGS.  1 - 14    for example purposes only. Controller device  10  may receive an indication of a stateful intent ( 1502 ). The data structure may include a plurality of nodes and a plurality of edges, each node of the plurality of nodes being representative of a respective network device of a plurality of network devices (e.g., elements  14  of  FIG.  1   ) and the plurality of edges defining relationships between the plurality of nodes. In some examples, the data structure is a unified graph model. The stateful intent may, for example, indicate a bandwidth between two network devices of the plurality of network devices. In some examples, the stateful intent may indicate one or more of a virtual private network connection between two network devices of the plurality of network devices, a labeled switch path between the two network devices of the plurality of network devices, an optical path between the two network devices of the plurality of network devices, or another stateful intent. 
     Controller device  10  may determine, using an abstract function configured at a node of the plurality of nodes, a stateless intent for implementing the stateful intent ( 1504 ). The stateful intent may be preprogrammed by a human user. For example, controller device  10  may generate a logical packet based on the stateful intent, inject the logical packet into the data structure and traverse the logical packet along the plurality of nodes. In some examples, traversing the logical packet comprises applying the abstract function to the logical packet when the logical packet traverses the node. 
     To determine the stateless intent, controller device  10  may determine a role assigned to the node and determine the stateless intent based on the role assigned to the node. For instance, controller device  10  may determine that a node is assigned as a core device and may determine the stateless intent based on the node being assigned as a core device. In some examples, controller device  10  may generate the logical packet to indicate an action. Examples of action may include one or more of connect, allow, block, or another action. For example, controller device  10  may be configured to select EVPN using Table 2 in response to determining a node (e.g., D2) has a label of “datacenter edge” and a logical packet indicating an action of “connectivity.” A role may include one or more of a datacenter edge device, an edge device, a layer 2 (L2) network device, or another role. Controller device  10  may generate the logical packet to indicate a source node of the plurality of nodes and a destination node of the plurality of nodes. In some examples, controller device  10  may generate the logical packet to indicate a quality of service (e.g., a bandwidth, latency, etc.). 
     To determine the stateless intent, controller device  10  may determine a dependent logical packet using an abstract function and a logical packet and inject the dependent logical packet towards a next node of the data structure representative of a next network device of the plurality of network devices. As shown in the example of  FIG.  4   , controller device  10  may apply instructions of abstract function F2 that generate RSVP LSP  414  and VPN  416  between site B and site A and generate a dependent logical packet  404  that traverses RSVP LSP  414  and VPN  416  to device D1, in response to logical packet  402 . When logical packet  404  reaches device D1, translation module  28  may apply instructions of abstract function F1 that generate RSVP LSP  418  and VPN  420  between site A and site C, in response to logical packet  404 . 
     Controller device  10  may generate low level configuration data for the plurality of network devices based on the stateless intent ( 1506 ). For example, controller  10  may generate, based on the stateless intent, low-level configuration data for element  14 A in a first vender-specific language supported by element  14 A and low-level configuration data for element  14 B in a second vender-specific language supported by element  14 B and not supported by element  14 A. Controller device  10  may interface with one or more of the plurality of network devices to configure the one or more of the plurality of network devices with the low level configuration data (e.g., device-level) ( 1508 ). For example, controller device  10  may apply the low-level configuration data for element  14 A to element  14 A and apply the low-level configuration data for element  14 B to element  14 B. 
     The techniques described in this disclosure may be implemented, at least in part, in hardware, software, firmware or any combination thereof. For example, various aspects of the described techniques may be implemented within one or more processors, including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combination of such components. The term “processor” or “processing circuitry” may generally refer to any of the foregoing logic circuitry, alone or in combination with other logic circuitry, or any other equivalent circuitry. A control unit comprising hardware may also perform one or more of the techniques of this disclosure. 
     Such hardware, software, and firmware may be implemented within the same device or within separate devices to support the various operations and functions described in this disclosure. In addition, any of the described units, modules or components may be implemented together or separately as discrete but interoperable logic devices. Depiction of different features as modules or units is intended to highlight different functional aspects and does not necessarily imply that such modules or units must be realized by separate hardware or software components. Rather, functionality associated with one or more modules or units may be performed by separate hardware or software components, or integrated within common or separate hardware or software components. 
     The techniques described in this disclosure may also be embodied or encoded in a computer-readable medium, such as a computer-readable storage medium, containing instructions. Instructions embedded or encoded in a computer-readable medium may cause a programmable processor, or other processor, to perform the method, e.g., when the instructions are executed. Computer-readable media may include non-transitory computer-readable storage media and transient communication media. Computer readable storage media, which is tangible and non-transitory, may include random access memory (RAM), read only memory (ROM), programmable read only memory (PROM), erasable programmable read only memory (EPROM), electronically erasable programmable read only memory (EEPROM), flash memory, a hard disk, a CD-ROM, a floppy disk, a cassette, magnetic media, optical media, or other computer-readable storage media. It should be understood that the term “computer-readable storage media” refers to physical storage media, and not signals, carrier waves, or other transient media. 
     Various examples have been described. These and other examples are within the scope of the following claims.