Patent Publication Number: US-11044170-B2

Title: Network migration assistant

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a Continuation of, and claims priority to, U.S. Non-Provisional patent application Ser. No. 15/790,412, filed Oct. 23, 2017, which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The subject matter of this disclosure relates in general to the field of computer networks, and more specifically for management of networked entities and resources. 
     BACKGROUND 
     A network administrator may be responsible for managing a large number of networked entities and resources distributed across one or more networks. These entities may be physical entities or logical entities. For example, the entities may include nodes, endpoints, machines, virtual machines, containers (an instance of container-based virtualization), tenants, endpoint groups, and applications. In addition to being different types, these entities may be grouped in various ways, located in different geographical locations, and/or serve different functions. The networked entities may be configured across one or more networks in many different ways and each configuration may have certain advantages and disadvantages with respect to performance, cost, etc. 
     In some cases, a network administrator may wish to alter the configuration of the networked entities by, for example, migrating one or more networked entities from one network to another. For example, some service providers provide one or more cloud services platforms that allow a network administrator to migrate networked entities to or from a cloud service platform. However, the decision to migrate networked entities from one network to another is a difficult one. Traditional approaches for managing large networks and determining whether and how to migrate certain entities require comprehensive knowledge on the part of highly specialized human operators because of the complexities of the networks, platforms, entities, and the interrelationships among the entities. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       In order to describe the manner in which the above-recited and other advantages and features of the disclosure can be obtained, a more particular description of the principles briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only embodiments of the disclosure and are not therefore to be considered to be limiting of its scope, the principles herein are described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
         FIG. 1  is a conceptual block diagram illustrating an example network migration system, in accordance with various embodiments of the subject technology; 
         FIG. 2  illustrates an example of a network environment, in accordance with an embodiment; 
         FIG. 3  illustrates an example of a network environment for migration, in accordance with an embodiment; 
         FIG. 4  shows an example process for assisting a network migration, in accordance with various embodiments of the subject technology; and 
         FIGS. 5A and 5B  illustrate examples of systems in accordance with some embodiments. 
     
    
    
     DESCRIPTION OF EXAMPLE EMBODIMENTS 
     The detailed description set forth below is intended as a description of various configurations of embodiments and is not intended to represent the only configurations in which the subject matter of this disclosure can be practiced. The appended drawings are incorporated herein and constitute a part of the detailed description. The detailed description includes specific details for the purpose of providing a more thorough understanding of the subject matter of this disclosure. However, it will be clear and apparent that the subject matter of this disclosure is not limited to the specific details set forth herein and may be practiced without these details. In some instances, structures and components are shown in block diagram form in order to avoid obscuring the concepts of the subject matter of this disclosure. 
     Overview 
     Additional features and advantages of the disclosure will be set forth in the description which follows, and in part will be obvious from the description, or can be learned by practice of the herein disclosed principles. The features and advantages of the disclosure can be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the disclosure will become more fully apparent from the following description and appended claims, or can be learned by the practice of the principles set forth herein. 
     Various aspects of the subject technology relate to assisting with the migration of networked entities. A system may be configured to collect operations data for a service from at least one endpoint host in a network, calculate at least one metric for the service based on the operations data, retrieve a migration configuration and platform data for a target platform, generate a predicted cost for the migration configuration based on the migration configuration, the at least one metric, and the platform data, and provide the predicted cost for the migration configuration to a user. 
     According to some embodiments, a system may be configured to store operations data for a first configuration of a first set of networked entities on at least one source platform, wherein the operations data are associated with a service hosted on the networked entities on the at least one source platform. The system may receive a second configuration for migrating the service from the at least one source platform to at least one destination platform, wherein the at least one destination platform is associated with platform data associated with a second set of networked entities. The system may further generate a predicted cost for the second configuration based on the operations data and the platform data for the at least one destination platform and provide the predicted cost for the migration configuration to a user. 
     EXAMPLE EMBODIMENTS 
     Various embodiments of the disclosure are discussed in detail below. While specific implementations are discussed, it should be understood that this is done for illustrative purposes only. A person skilled in the relevant art will recognize that other components and configurations may be used without departing from the spirit and scope of the disclosure. 
     Various embodiments of the subject technology relate to a system configured to assist a network administrator with the possible migration of networked entities from one network to another. The system may provide the network administrator with information, metrics, insights, candidate configurations, or other information that may help the network administrator determine whether to migrate one or more networked entities, how to migrate the one or more entities, predict changes in performance or cost associated with a migration configuration, and/or execute a migration. 
     A network administrator or a team of network administrators often manage a large number of networked entities. The entities may include applications, endpoint groups, tenants, virtual machines, or containers. Each of these networked entities has their own performance characteristics, resource requirements, and costs, which may all vary over time. There are also many options for hosting the various networked entities managed by the network administrators. For example, one or more networked entities may be hosted on one or more host platforms. These host platforms may include local machines, one or more machines in one or more enterprise networks, or cloud services platforms provided by third parties. 
     There are various considerations that network administrators should consider when deciding where to host networked entities. However, because of the complexity and lack of information on the various factors, some of the factors are not adequately considered when determining where to host or migrate networked entities. For example, the network administrators need to consider how a networked entity will perform on the host platform, the cost of hosting each networked entity on the host platform, and how the hosting configuration of the other networked entities will affect the networked entity. These considerations are often hard to predict, especially with respect to a large number of networked entities with a complex web of interoperability and interdependence. 
     Various embodiments of the subject technology address these and other technical problems by assisting network administrators by providing network administrators with guidance and information about various migration configurations and their associated costs. Aspects may relate to collecting operations data for networked entities and calculating various metrics for the networked entities based on the operations data. One or more migration configurations may be retrieved along with platform data for one or more host platforms. Using these inputs, a predicted cost for each migration configuration may be calculated and provided to a user. 
     Example embodiments described herein with reference to the accompanying figures provide an improvement to one or more aspects of existing methods and systems for optimizing performance of network migration systems and tools. Network migration plays an important role in the technological field of network management, internet/network security, datacenter technology, and other modern network related technologies that are rooted in computer technologies. Modern datacenter and network configurations are increasingly migrating either entirely or partially to cloud providers. Aspects of the subject technology reduce the time and computing resources (e.g., CPU, bandwidth, memory, etc.) needed to identify how a migration configuration affects the cost, performance, and/or computing resources needed by a data center or other network entity. 
       FIG. 1  is a conceptual block diagram illustrating an example network migration system  100 , in accordance with various embodiments of the subject technology. The network migration system  100  can include a configuration manager  102 , sensor(s)  104 , a collector module  106 , a data mover module  108 , an analytics engine  110 , and a presentation module  112 . In  FIG. 1 , the analytics engine  110  is also shown in communication with out-of-band data sources  114 , third party data sources  116 , and a network controller  118 . 
     The configuration manager  102  can be used to provision and maintain the sensors  104 , including installing sensor software or firmware in various nodes of a network, configuring the sensors  104 , updating the sensor software or firmware, among other sensor management tasks. For example, the sensors  104  can be implemented as virtual partition images (e.g., virtual machine (VM) images or container images), and the configuration manager  102  can distribute the images to host machines. In general, a virtual partition can be an instance of a VM, container, sandbox, or other isolated software environment. The software environment can include an operating system and application software. For software running within a virtual partition, the virtual partition can appear to be, for example, one of many servers or one of many operating systems executed on a single physical server. The configuration manager  102  can instantiate a new virtual partition or migrate an existing partition to a different physical server. The configuration manager  102  can also be used to configure the new or migrated sensor. 
     The configuration manager  102  can monitor the health of the sensors  104 . For example, the configuration manager  102  can request for status updates and/or receive heartbeat messages, initiate performance tests, generate health checks, and perform other health monitoring tasks. In some embodiments, the configuration manager  102  can also authenticate the sensors  104 . For instance, the sensors  104  can be assigned a unique identifier, such as by using a one-way hash function of a sensor&#39;s basic input/out system (BIOS) universally unique identifier (UUID) and a secret key stored by the configuration image manager  102 . The UUID can be a large number that can be difficult for a malicious sensor or other device or component to guess. In some embodiments, the configuration manager  102  can keep the sensors  104  up to date by installing the latest versions of sensor software and/or applying patches. The configuration manager  102  can obtain these updates automatically from a local source or the Internet. 
     The sensors  104  can reside on various nodes of a network, such as a virtual partition (e.g., VM or container); a hypervisor or shared kernel managing one or more virtual partitions and/or physical servers, an application-specific integrated circuit (ASIC) of a switch, router, gateway, or other networking device, or a packet capture (pcap) appliance (e.g., a standalone packet monitor, a device connected to a network devices monitoring port, a device connected in series along a main trunk of a datacenter, or similar device), or other entity in a network. The sensors  104  can monitor network traffic between nodes, and send network traffic data and corresponding data (e.g., host data, process data, user data, etc.) to the collectors  108  for storage. For example, the sensors  104  can sniff packets being sent over its hosts&#39; physical or virtual network interface card (NIC), or individual processes can be configured to report network traffic and corresponding data to the sensors  104 . Incorporating the sensors  104  on multiple nodes and within multiple partitions of some nodes of the network can provide for robust capture of network traffic and corresponding data from each hop of data transmission. In some embodiments, each node of the network (e.g., VM, container, or other virtual partition, hypervisor, shared kernel, or physical server, ASIC, pcap, etc.) includes a respective sensor  104 . However, it should be understood that various software and hardware configurations can be used to implement the sensor network  104 . 
     As the sensors  104  capture communications and corresponding data, they can continuously send network traffic data to the collectors  108 . The network traffic data can include metadata relating to a packet, a collection of packets, a flow, a bidirectional flow, a group of flows, a session, or a network communication of another granularity. That is, the network traffic data can generally include any information describing communication on all layers of the Open Systems Interconnection (OSI) model. For example, the network traffic data can include source/destination MAC address, source/destination IP address, protocol, port number, etc. In some embodiments, the network traffic data can also include summaries of network activity or other network statistics such as number of packets, number of bytes, number of flows, bandwidth usage, response time, latency, packet loss, jitter, and other network statistics. 
     The sensors  104  can also determine additional data, included as part of gathered network traffic data, for each session, bidirectional flow, flow, packet, or other more granular or less granular network communication. The additional data can include host and/or endpoint information, virtual partition information, sensor information, process information, user information, tenant information, application information, network topology, application dependency mapping, cluster information, or other information corresponding to each flow. 
     In some embodiments, the sensors  104  can perform some preprocessing of the network traffic and corresponding data before sending the data to the collectors  108 . For example, the sensors  104  can remove extraneous or duplicative data or they can create summaries of the data (e.g., latency, number of packets per flow, number of bytes per flow, number of flows, etc.). In some embodiments, the sensors  104  can be configured to only capture certain types of network information and disregard the rest. In some embodiments, the sensors  104  can be configured to capture only a representative sample of packets (e.g., every 1,000th packet or other suitable sample rate) and corresponding data. 
     Since the sensors  104  can be located throughout the network, network traffic and corresponding data can be collected from multiple vantage points or multiple perspectives in the network to provide a more comprehensive view of network behavior. The capture of network traffic and corresponding data from multiple perspectives rather than just at a single sensor located in the data path or in communication with a component in the data path, allows the data to be correlated from the various data sources, which can be used as additional data points by the analytics engine  110 . Further, collecting network traffic and corresponding data from multiple points of view ensures more accurate data is captured. For example, a conventional sensor network can be limited to sensors running on external-facing network devices (e.g., routers, switches, network appliances, etc.) such that east-west traffic, including VM-to-VM or container-to-container traffic on a same host, may not be monitored. In addition, packets that are dropped before traversing a network device or packets containing errors cannot be accurately monitored by the conventional sensor network. The sensor network  104  of various embodiments substantially mitigates or eliminates these issues altogether by locating sensors at multiple points of potential failure. Moreover, the network migration system  100  can verify multiple instances of data for a flow (e.g., source endpoint flow data, network device flow data, and endpoint flow data) against one another. 
     In some embodiments, the network migration system  100  can assess a degree of accuracy of flow data sets from multiple sensors and utilize a flow data set from a single sensor determined to be the most accurate and/or complete. The degree of accuracy can be based on factors such as network topology (e.g., a sensor closer to the source can be more likely to be more accurate than a sensor closer to the destination), a state of a sensor or a node hosting the sensor (e.g., a compromised sensor/node can have less accurate flow data than an uncompromised sensor/node), or flow data volume (e.g., a sensor capturing a greater number of packets for a flow can be more accurate than a sensor capturing a smaller number of packets). 
     In some embodiments, the network migration system  100  can assemble the most accurate flow data set and corresponding data from multiple sensors. For instance, a first sensor along a data path can capture data for a first packet of a flow but can be missing data for a second packet of the flow while the situation is reversed for a second sensor along the data path. The network migration system  100  can assemble data for the flow from the first packet captured by the first sensor and the second packet captured by the second sensor. 
     As discussed, the sensors  104  can send network traffic and corresponding data to the collectors  106 . In some embodiments, each sensor can be assigned to a primary collector and a secondary collector as part of a high availability scheme. If the primary collector fails or communications between the sensor and the primary collector are not otherwise possible, a sensor can send its network traffic and corresponding data to the secondary collector. In other embodiments, the sensors  104  are not assigned specific collectors but the network migration system  100  can determine an optimal collector for receiving the network traffic and corresponding data through a discovery process. In such embodiments, a sensor can change where it sends it network traffic and corresponding data if its environments changes, such as if a default collector fails or if the sensor is migrated to a new location and it would be optimal for the sensor to send its data to a different collector. For example, it can be preferable for the sensor to send its network traffic and corresponding data on a particular path and/or to a particular collector based on latency, shortest path, monetary cost (e.g., using private resources versus a public resources provided by a public cloud provider), error rate, or some combination of these factors. In other embodiments, a sensor can send different types of network traffic and corresponding data to different collectors. For example, the sensor can send first network traffic and corresponding data related to one type of process to one collector and second network traffic and corresponding data related to another type of process to another collector. 
     The collectors  106  can be any type of storage medium that can serve as a repository for the network traffic and corresponding data captured by the sensors  104 . In some embodiments, data storage for the collectors  106  is located in an in-memory database, such as dashDB from IBM®, although it should be appreciated that the data storage for the collectors  106  can be any software and/or hardware capable of providing rapid random access speeds typically used for analytics software. In various embodiments, the collectors  106  can utilize solid state drives, disk drives, magnetic tape drives, or a combination of the foregoing according to cost, responsiveness, and size requirements. Further, the collectors  106  can utilize various database structures such as a normalized relational database or a NoSQL database, among others. 
     In some embodiments, the collectors  106  can only serve as network storage for the network migration system  100 . In such embodiments, the network migration system  100  can include a data mover module  108  for retrieving data from the collectors  106  and making the data available to network clients, such as the components of the analytics engine  110 . In effect, the data mover module  108  can serve as a gateway for presenting network-attached storage to the network clients. In other embodiments, the collectors  106  can perform additional functions, such as organizing, summarizing, and preprocessing data. For example, the collectors  106  can tabulate how often packets of certain sizes or types are transmitted from different nodes of the network. The collectors  106  can also characterize the traffic flows going to and from various nodes. In some embodiments, the collectors  106  can match packets based on sequence numbers, thus identifying traffic flows and connection links. As it can be inefficient to retain all data indefinitely in certain circumstances, in some embodiments, the collectors  106  can periodically replace detailed network traffic data with consolidated summaries. In this manner, the collectors  106  can retain a complete dataset describing one period (e.g., the past minute or other suitable period of time), with a smaller dataset of another period (e.g., the previous 2-10 minutes or other suitable period of time), and progressively consolidate network traffic and corresponding data of other periods of time (e.g., day, week, month, year, etc.). In some embodiments, network traffic and corresponding data for a set of flows identified as normal or routine can be winnowed at an earlier period of time while a more complete data set can be retained for a lengthier period of time for another set of flows identified as anomalous or as an attack. 
     The analytics engine  110  can generate analytics using data collected by the sensors  104 . Analytics generated by the analytics engine  110  can include applicable analytics of nodes or a cluster of nodes operating in a network. For example, analytics generated by the analytics engine  110  can include one or a combination of information related to flows of data through nodes, detected attacks on a network or nodes of a network, applications at nodes or distributed across the nodes, application dependency mappings for applications at nodes, policies implemented at nodes, and actual policies enforced at nodes. 
     In some embodiments, the analytics engine  110  can be used to generate various metrics regarding one or more migration configurations for networked entities. The metrics may relate to a monetary cost, performance metrics, etc. For example, a migration configuration may assign a number of networked entities to one or more host platforms. Based on the information contained in the data lake  130 , the analytics engine may determine metrics associated with the placement of each of the networked entities in the migration configuration at the assigned host platform. 
     The analytics engine  110  can include a data lake  130 , an application dependency mapping (ADM) module  140 , and elastic processing engines  150 . The data lake  130  is a large-scale storage repository that provides massive storage for various types of data, enormous processing power, and the ability to handle nearly limitless concurrent tasks or jobs. In some embodiments, the data lake  130  is implemented using the Hadoop® Distributed File System (HDFS™) from Apache® Software Foundation of Forest Hill, Md. HDFS™ is a highly scalable and distributed file system that can scale to thousands of cluster nodes, millions of files, and petabytes of data. HDFS™ is optimized for batch processing where data locations are exposed to allow computations to take place where the data resides. HDFS™ provides a single namespace for an entire cluster to allow for data coherency in a write-once, read-many access model. That is, clients can only append to existing files in the node. In HDFS™, files are separated into blocks, which are typically 64 MB in size and are replicated in multiple data nodes. Clients access data directly from data nodes. 
     In some embodiments, the data mover  108  receives raw network traffic and corresponding data from the collectors  106  and distributes or pushes the data to the data lake  130 . The data lake  130  can also receive and store out-of-band data  114 , such as statuses on power levels, network availability, server performance, temperature conditions, cage door positions, and other data from internal sources, and third party data  116 , such as platform data for a host platform, security reports (e.g., provided by Cisco® Systems, Inc. of San Jose, Calif., Arbor Networks® of Burlington, Mass., Symantec® Corp. of Sunnyvale, Calif., Sophos® Group plc of Abingdon, England, Microsoft® Corp. of Seattle, Wash., Verizon® Communications, Inc. of New York, N.Y., among others), geolocation data, IP watch lists, Whois data, configuration management database (CMDB) or configuration management system (CMS) as a service, and other data from external sources. In other embodiments, the data lake  130  can instead fetch or pull raw traffic and corresponding data from the collectors  106  and relevant data from the out-of-band data sources  114  and the third party data sources  116 . In yet other embodiments, the functionality of the collectors  106 , the data mover  108 , the out-of-band data sources  114 , the third party data sources  116 , and the data lake  130  can be combined. Various combinations and configurations are possible as would be known to one of ordinary skill in the art. 
     Each component of the data lake  130  can perform certain processing of the raw network traffic data and/or other data (e.g., host data, process data, user data, out-of-band data or third party data) to transform the raw data to a form useable by the elastic processing engines  150 . In some embodiments, the data lake  130  can include repositories for flow attributes  132 , host and/or endpoint attributes  134 , process attributes  136 , and policy attributes  138 . In some embodiments, the data lake  130  can also include repositories for VM or container attributes, application attributes, tenant attributes, network topology, application dependency maps, cluster attributes, etc. 
     The flow attributes  132  relate to information about flows traversing the network. A flow is generally one or more packets sharing certain attributes that are sent within a network within a specified period of time. The flow attributes  132  can include packet header fields such as a source address (e.g., Internet Protocol (IP) address, Media Access Control (MAC) address, Domain Name System (DNS) name, or other network address), source port, destination address, destination port, protocol type, class of service, among other fields. The source address can correspond to a first endpoint (e.g., network device, physical server, virtual partition, etc.) of the network, and the destination address can correspond to a second endpoint, a multicast group, or a broadcast domain. The flow attributes  132  can also include aggregate packet data such as flow start time, flow end time, number of packets for a flow, number of bytes for a flow, the union of TCP flags for a flow, among other flow data. 
     The host and/or endpoint attributes  134  describe host and/or endpoint data for each flow, and can include host and/or endpoint name, network address, operating system, CPU usage, network usage, disk space, ports, logged users, scheduled jobs, open files, and information regarding files and/or directories stored on a host and/or endpoint (e.g., presence, absence, or modifications of log files, configuration files, device special files, or protected electronic information). As discussed, in some embodiments, the host and/or endpoints attributes  134  can also include the out-of-band data  114  regarding hosts such as power level, temperature, and physical location (e.g., room, row, rack, cage door position, etc.) or the third party data  116  such as whether a host and/or endpoint is on an IP watch list or otherwise associated with a security threat, Whois data, or geocoordinates. In some embodiments, the out-of-band data  114  and the third party data  116  can be associated by platform, process, user, flow, or other more granular or less granular network element or network communication. 
     The process attributes  136  relate to process data corresponding to each flow, and can include process name (e.g., bash, httpd, netstat, etc.), ID, parent process ID, path (e.g., /usr2/username/bin/, /usr/local/bin, /usr/bin, etc.), CPU utilization, memory utilization, memory address, scheduling information, nice value, flags, priority, status, start time, terminal type, CPU time taken by the process, the command that started the process, and information regarding a process owner (e.g., user name, ID, user&#39;s real name, e-mail address, user&#39;s groups, terminal information, login time, expiration date of login, idle time, and information regarding files and/or directories of the user). 
     The policy attributes  138  contain information relating to network policies. Policies establish whether a particular flow is allowed or denied by the network as well as a specific route by which a packet traverses the network. Policies can also be used to mark packets so that certain kinds of traffic receive differentiated service when used in combination with queuing techniques such as those based on priority, fairness, weighted fairness, token bucket, random early detection, round robin, among others. The policy attributes  138  can include policy statistics such as a number of times a policy was enforced or a number of times a policy was not enforced. The policy attributes  138  can also include associations with network traffic data. F or example, flows found to be non-conformant can be linked or tagged with corresponding policies to assist in the investigation of non-conformance. 
     The analytics engine  110  can include any number of engines  150 , including for example, a flow engine  152  for identifying flows (e.g., flow engine  152 ) or an attacks engine  154  for identify attacks to the network. In some embodiments, the analytics engine can include a separate distributed denial of service (DDoS) attack engine  155  for specifically detecting DDoS attacks. In other embodiments, a DDoS attack engine can be a component or a sub-engine of a general attacks engine. In some embodiments, the attacks engine  154  and/or the DDoS engine  155  can use machine learning techniques to identify security threats to a network. For example, the attacks engine  154  and/or the DDoS engine  155  can be provided with examples of network states corresponding to an attack and network states corresponding to normal operation. The attacks engine  154  and/or the DDoS engine  155  can then analyze network traffic data to recognize when the network is under attack. In some embodiments, the network can operate within a trusted environment for a time to establish a baseline for normal network operation for the attacks engine  154  and/or the DDoS. 
     The analytics engine  110  can further include a search engine  156 . The search engine  156  can be configured, for example to perform a structured search, an NLP (Natural Language Processing) search, or a visual search. Data can be provided to the engines from one or more processing components. 
     The analytics engine  110  can also include a policy engine  158  that manages network policy, including creating and/or importing policies, monitoring policy conformance and non-conformance, enforcing policy, simulating changes to policy or network elements affecting policy, among other policy-related tasks. 
     The ADM module  140  can determine dependencies of applications of the network. That is, particular patterns of traffic can correspond to an application, and the interconnectivity or dependencies of the application can be mapped to generate a graph for the application (i.e., an application dependency mapping). In this context, an application refers to a set of networking components that provides connectivity for a given set of workloads. For example, in a conventional three-tier architecture for a web application, first endpoints of the web tier, second endpoints of the application tier, and third endpoints of the data tier make up the web application. The ADM module  140  can receive input data from various repositories of the data lake  130  (e.g., the flow attributes  132 , the host and/or endpoint attributes  134 , the process attributes  136 , etc.). The ADM module  140  can analyze the input data to determine that there is first traffic flowing between external endpoints on port  80  of the first endpoints corresponding to Hypertext Transfer Protocol (HTTP) requests and responses. The input data can also indicate second traffic between first ports of the first endpoints and second ports of the second endpoints corresponding to application server requests and responses and third traffic flowing between third ports of the second endpoints and fourth ports of the third endpoints corresponding to database requests and responses. The ADM module  140  can define an ADM for the web application as a three-tier application including a first EPG comprising the first endpoints, a second EPG comprising the second endpoints, and a third EPG comprising the third endpoints. 
     The presentation module  116  can include an application programming interface (API) or command line interface (CLI)  160 , a security information and event management (SIEM) interface  162 , and a web front-end  164 . As the analytics engine  110  processes network traffic and corresponding data and generates analytics data, the analytics data may not be in a human-readable form or it can be too voluminous for a user to navigate. The presentation module  116  can take the analytics data generated by analytics engine  110  and further summarize, filter, and organize the analytics data as well as create intuitive presentations for the analytics data. 
     In some embodiments, the API or CLI  160  can be implemented using Hadoop® Hive from Apache® for the back end, and Java® Database Connectivity (JDBC) from Oracle® Corporation of Redwood Shores, Calif., as an API layer. Hive is a data warehouse infrastructure that provides data summarization and ad hoc querying. Hive provides a mechanism to query data using a variation of structured query language (SQL) that is called HiveQL. JDBC is an API for the programming language Java®, which defines how a client can access a database. 
     In some embodiments, the SIEM interface  162  can be implemented using Hadoop® Kafka for the back end, and software provided by Splunk®, Inc. of San Francisco, Calif. as the SIEM platform. Kafka is a distributed messaging system that is partitioned and replicated. Kafka uses the concept of topics. Topics are feeds of messages in specific categories. In some embodiments, Kafka can take raw packet captures and telemetry information from the data mover  108  as input, and output messages to a SIEM platform, such as Splunk®. The Splunk® platform is utilized for searching, monitoring, and analyzing machine-generated data. 
     In some embodiments, the web front-end  164  can be implemented using software provided by MongoDB®, Inc. of New York, N.Y. and Hadoop® ElasticSearch from Apache® for the back-end, and Ruby on Rails™ as the web application framework. MongoDB® is a document-oriented NoSQL database based on documents in the form of JavaScript® Object Notation (JSON) with dynamic schemas. ElasticSearch is a scalable and real-time search and analytics engine that provides domain-specific language (DSL) full querying based on JSON. Ruby on Rails™ is model-view-controller (MVC) framework that provides default structures for a database, a web service, and web pages. Ruby on Rails™ relies on web standards such as JSON or extensible markup language (XML) for data transfer, and hypertext markup language (HTML), cascading style sheets, (CSS), and JavaScript® for display and user interfacing. 
     Although  FIG. 1  illustrates an example configuration of the various components of a network migration system, those of skill in the art will understand that the components of the network migration system  100  or any system described herein can be configured in a number of different ways and can include any other type and number of components. For example, the sensors  104 , the collectors  106 , the data mover  108 , and the data lake  130  can belong to one hardware and/or software module or multiple separate modules. Other modules can also be combined into fewer components and/or further divided into more components. 
       FIG. 2  illustrates an example of a network environment  200 , in accordance with an embodiment. In some embodiments, a network migration system, such as the network migration system  100  of  FIG. 1 , can be implemented in the network environment  200 . It should be understood that, for the network environment  200  and any environment discussed herein, there can be additional or fewer nodes, devices, links, networks, or components in similar or alternative configurations. Embodiments with different numbers and/or types of clients, networks, nodes, cloud components, servers, software components, devices, virtual or physical resources, configurations, topologies, services, appliances, deployments, or network devices are also contemplated herein. Further, the network environment  200  can include any number or type of resources, which can be accessed and utilized by clients or tenants. The illustrations and examples provided herein are for clarity and simplicity. 
     The network environment  200  can include a network fabric  202 , a Layer 2 (L2) network  204 , a Layer 3 (L3) network  206 , and servers  208   a ,  208   b ,  208   c ,  208   d , and  208   e  (collectively,  208 ). The network fabric  202  can include spine switches  210   a ,  210   b ,  210   c , and  210   d  (collectively, “ 210 ”) and leaf switches  212   a ,  212   b ,  212   c ,  212   d , and  212   e  (collectively, “ 212 ”). The spine switches  210  can connect to the leaf switches  212  in the network fabric  202 . The leaf switches  212  can include access ports (or non-fabric ports) and fabric ports. The fabric ports can provide uplinks to the spine switches  210 , while the access ports can provide connectivity to endpoints (e.g., the servers  208 ), internal networks (e.g., the L2 network  204 ), or external networks (e.g., the L3 network  206 ). 
     The leaf switches  212  can reside at the edge of the network fabric  202 , and can thus represent the physical network edge. For instance, in some embodiments, the leaf switches  212   d  and  212   e  operate as border leaf switches in communication with edge devices  214  located in the external network  206 . The border leaf switches  212   d  and  212   e  can be used to connect any type of external network device, service (e.g., firewall, deep packet inspector, traffic monitor, load balancer, etc.), or network (e.g., the L3 network  206 ) to the fabric  202 . 
     Although the network fabric  202  is illustrated and described herein as an example leaf-spine architecture, one of ordinary skill in the art will readily recognize that various embodiments can be implemented based on any network topology, including any datacenter or cloud network fabric. Indeed, other architectures, designs, infrastructures, and variations are contemplated herein. For example, the principles disclosed herein are applicable to topologies including three-tier (including core, aggregation, and access levels), fat tree, mesh, bus, hub and spoke, etc. Thus, in some embodiments, the leaf switches  212  can be top-of-rack switches configured according to a top-of-rack architecture. In other embodiments, the leaf switches  212  can be aggregation switches in any particular topology, such as end-of-row or middle-of-row topologies. In some embodiments, the leaf switches  212  can also be implemented using aggregation switches. 
     Moreover, the topology illustrated in  FIG. 2  and described herein is readily scalable and can accommodate a large number of components, as well as more complicated arrangements and configurations. For example, the network can include any number of fabrics  202 , which can be geographically dispersed or located in the same geographic area. Thus, network nodes can be used in any suitable network topology, which can include any number of servers, virtual machines or containers, switches, routers, appliances, controllers, gateways, or other nodes interconnected to form a large and complex network. Nodes can be coupled to other nodes or networks through one or more interfaces employing any suitable wired or wireless connection, which provides a viable pathway for electronic communications. 
     Network communications in the network fabric  202  can flow through the leaf switches  212 . In some embodiments, the leaf switches  212  can provide endpoints (e.g., the servers  208 ), internal networks (e.g., the L2 network  204 ), or external networks (e.g., the L3 network  206 ) access to the network fabric  202 , and can connect the leaf switches  212  to each other. In some embodiments, the leaf switches  212  can connect endpoint groups (EPGs) to the network fabric  202 , internal networks (e.g., the L2 network  204 ), and/or any external networks (e.g., the L3 network  206 ). EPGs are groupings of applications, or application components, and tiers for implementing forwarding and policy logic. EPGs can allow for separation of network policy, security, and forwarding from addressing by using logical application boundaries. EPGs can be used in the network environment  200  for mapping applications in the network. For example, EPGs can comprise a grouping of endpoints in the network indicating connectivity and policy for applications. 
     As discussed, the servers  208  can connect to the network fabric  202  via the leaf switches  212 . For example, the servers  208   a  and  208   b  can connect directly to the leaf switches  212   a  and  212   b , which can connect the servers  208   a  and  208   b  to the network fabric  202  and/or any of the other leaf switches. The servers  208   c  and  208   d  can connect to the leaf switches  212   b  and  212   c  via the L2 network  204 . The servers  208   c  and  208   d  and the L2 network  204  make up a local area network (LAN). LANs can connect nodes over dedicated private communications links located in the same general physical location, such as a building or campus. 
     The WAN  206  can connect to the leaf switches  212   d  or  212   e  via the L3 network  206 . WANs can connect geographically dispersed nodes over long-distance communications links, such as common carrier telephone lines, optical light paths, synchronous optical networks (SONET), or synchronous digital hierarchy (SDH) links. LANs and WANs can include L2 and/or L3 networks and endpoints. 
     The Internet is an example of a WAN that connects disparate networks throughout the world, providing global communication between nodes on various networks. The nodes typically communicate over the network by exchanging discrete frames or packets of data according to predefined protocols, such as the Transmission Control Protocol/Internet Protocol (TCP/IP). In this context, a protocol can refer to a set of rules defining how the nodes interact with each other. Computer networks can be further interconnected by an intermediate network node, such as a router, to extend the effective size of each network. The endpoints  208  can include any communication device or component, such as a computer, server, blade, hypervisor, virtual machine, container, process (e.g., running on a virtual machine), switch, router, gateway, host, device, external network, etc. 
     In some embodiments, the network environment  200  also includes a network controller running on the host  208   a . The network controller is implemented using the Application Policy Infrastructure Controller (APIC™) from Cisco®. The APIC™ provides a centralized point of automation and management, policy programming, application deployment, and health monitoring for the fabric  202 . In some embodiments, the APIC™ is operated as a replicated synchronized clustered controller. In other embodiments, other configurations or software-defined networking (SDN) platforms can be utilized for managing the fabric  202 . 
     In some embodiments, a physical server  208  can have instantiated thereon a hypervisor  216  for creating and running one or more virtual switches (not shown) and one or more virtual machines  218 , as shown for the host  208   b . In other embodiments, physical servers can run a shared kernel for hosting containers. In yet other embodiments, the physical server  208  can run other software for supporting other virtual partitioning approaches. Networks in accordance with various embodiments can include any number of physical servers hosting any number of virtual machines, containers, or other virtual partitions. Hosts can also comprise blade/physical servers without virtual machines, containers, or other virtual partitions, such as the servers  208   a ,  208   c ,  208   d , and  208   e.    
     The network environment  200  can also integrate a network migration system, such as the network migration system  100  shown in  FIG. 1 . For example, the network migration system of  FIG. 2  includes sensors  220   a ,  220   b ,  220   c , and  220   d  (collectively, “ 220 ”), collectors  222 , and an analytics engine, such as the analytics engine  110  of  FIG. 1 , executing on the server  208   e . The analytics engine  208   e  can receive and process network traffic data collected by the collectors  222  and detected by the sensors  220  placed on nodes located throughout the network environment  200 . Although the analytics engine  208   e  is shown to be a standalone network appliance in  FIG. 2 , it will be appreciated that the analytics engine  208   e  can also be implemented as a virtual partition (e.g., VM or container) that can be distributed onto a host or cluster of hosts, software as a service (SaaS), or other suitable method of distribution. In some embodiments, the sensors  220  run on the leaf switches  212  (e.g., the sensor  220   a ), the hosts  208  (e.g., the sensor  220   b ), the hypervisor  216  (e.g., the sensor  220   c ), and the VMs  218  (e.g., the sensor  220   d ). In other embodiments, the sensors  220  can also run on the spine switches  210 , virtual switches, service appliances (e.g., firewall, deep packet inspector, traffic monitor, load balancer, etc.) and in between network elements. In some embodiments, sensors  220  can be located at each (or nearly every) network component to capture granular packet statistics and data at each hop of data transmission. In other embodiments, the sensors  220  may not be installed in all components or portions of the network (e.g., shared hosting environment in which customers have exclusive control of some virtual machines). 
     As shown in  FIG. 2 , a host can include multiple sensors  220  running on the host (e.g., the host sensor  220   b ) and various components of the host (e.g., the hypervisor sensor  220   c  and the VM sensor  220   d ) so that all (or substantially all) packets traversing the network environment  200  can be monitored. For example, if one of the VMs  218  running on the host  208   b  receives a first packet from the WAN  206 , the first packet can pass through the border leaf switch  212   d , the spine switch  210   b , the leaf switch  212   b , the host  208   b , the hypervisor  216 , and the VM. Since all or nearly all of these components contain a respective sensor, the first packet will likely be identified and reported to one of the collectors  222 . As another example, if a second packet is transmitted from one of the VMs  218  running on the host  208   b  to the host  208   d , sensors installed along the data path, such as at the VM  218 , the hypervisor  216 , the host  208   b , the leaf switch  212   b , and the host  208   d  will likely result in capture of metadata from the second packet. 
     The network migration system  100  shown in  FIG. 1  can be used to gather network traffic data and generate analytics for networked entities. Specifically, the network migration system  100  can gather network traffic data and generate analytics for networked entities within one or more networks or host platforms. Although  FIG. 2  illustrates one network environment  200 , in some embodiments, a network migration system may communicate with multiple network environments (e.g., other host platforms) and/or multiple network fabrics. 
     In some cases, a network administrator may wish to migrate applications, services, or other networked entities from one host platform to another. Migration may allow for reduce costs, increased performance, improved scalability, or other advantages. 
       FIG. 3  illustrates an example of a network environment  300  for migration, in accordance with an embodiment. The network environment  300  includes a first host platform  302  and a second host platform  304  for illustrative purposes with the understanding that additional host platforms are also contemplated. The first host platform  302  may be, for example, an enterprise network while the second host platform  304  may be a cloud services platform provided by a third party. 
     The network administrator may contemplate a migration configuration for migrating application  314 , currently hosted on one or more machines  312  or virtual machines (VMs) of the first host platform  302 , to one or more machines  320  or host machines of the second host platform  304 . Although  FIG. 3  illustrates application  314  being hosted by a single machine  312  or virtual machine, in some cases, the application may be hosted by multiple machines or VMs on a source host platform and can be migrated to multiple machines or VMs on a destination host platform. Furthermore, the machines/VMs on the source host platform may have different specifications and capabilities from the machines/VMs on the destination host platform. 
     According to various embodiments of the subject technology, the migration of the application  314  from the source host platform to the destination host platform is not a mere cloning of a machine on the source host platform onto a machine on the destination host platform. In many cases, each machine (or VM) may host multiple applications or services or parts of multiple applications or services. 
     As a result of the complexities of the various factors associated with migrating applications or services from one host platform to another host platform, network administrators are often unaware of the impact of a migration configuration with regards to cost and performance. Even in cases where an estimate for the cost and performance is provided, the estimates are often highly inaccurate and misleading. Embodiments of the subject technology leverage the network migration system  100  shown in  FIG. 1  to provide more accurate estimates of the costs and performance associated with a migration configuration. 
       FIG. 4  shows an example process  400  for assisting a network migration, in accordance with various embodiments of the subject technology. It should be understood that, for any process discussed herein, there can be additional, fewer, or alternative steps performed in similar or alternative orders, or in parallel, within the scope of the various embodiments unless otherwise stated. The process  400  can be performed by a network migration system or similar system. 
     At operation  405 , the system collects operations data for a service from at one or more sensors. The sensors may be deployed on endpoints or other nodes in one or more networks and eventually provided to an analytics engine for processing (e.g., via collectors and a data mover as illustrated in  FIG. 1 ). A service may be any logical construct configured to serve a function in the networking environment. In some cases more than one service may operate on a single physical machine in the networking environment. The service may be in the form of, for example, an application or portion of an application hosted on one or more endpoints managed by a network administrator, an endpoint group configured to serve a function, etc. In some embodiments, the sensors can perform some preprocessing of the network traffic and corresponding data before sending the data to the collectors. In other embodiments, the data may be processed at the collectors, data mover, and/or the analytics engine. 
     The collected operations data associated with one or more services in a network environment may include data flows (e.g., network traffic) between services, an amount of processor time needed by each service, an amount of memory needed for each service, an amount of storage/disk space needed for each service, a number (or listing) of host entities that the service runs on, identifiers or specifications for each host entity that the service runs on, or other computing resources needed for each service. The data flow information may be for one or more periods of time and include an amount of data transferred by a service, an amount of data received by the service, an amount of data transferred from the service to another specified service. The collected operations data may be stored in a database in one or more records keyed to an identifier (e.g., a name or ID) for each service. 
     At operation  410 , one or more metrics for the service is calculated based on the collected operations data. The metrics may include average values, max/min values, trends, or other metrics for collected operations data. The metrics may be based on the operation data for a service running on a particular host (e.g., an endpoint machine) and/or the service running across all hosts in the network environment. 
     At operations  415 , the system may also retrieve a migration configuration and platform data for a target platform. The platform data may be retrieved from a third party via the network (e.g. a system associated with the target platform) and may include data associated with the target platform. For example, the platform data may include one or more physical locations where the target platform is located, pricing information for the target platform, target platform features and options, hardware and/or software specifications for host entities (e.g., endpoint machines, virtual machines, containers, etc.), or platform options. The pricing information may include flat fees, fees based on usage, fees based on features used, or a combination of various fees. 
     The migration configuration may be received from a network administrator. For example, the system may provide a user interface accessible via the network for a network administrator to alter a current configuration of networked entities and/or generate a migration configuration for the networked entities and submit the migration configuration to the system. According to other embodiments, the system may generate the migration configuration based on the collected operations data, metrics generated based on the operations data, the platform data, or other information. For example, the network administrator may provide additional preferences or constraints based on which one or more migration configurations may be generated. 
     At operation  420 , the system generates a predicted cost for the migration configuration based on the migration configuration, the at least one generated metric, and the platform data. For example, the migration configuration may specify that a service (e.g., a web application) is to be migrated from a source platform (e.g., an enterprise network) to a destination platform (e.g., a cloud provider platform). The system may calculate, based on the operations data and the migration configuration, the amount of resourced needed at on the destination platform and determine, based on the platform data (e.g., hardware and/or software specifications for the destination platform) for the destination platform, how to effectively provision those resources on the destination platform. 
     Based on the provisioning and the pricing information for the destination platform, the system may calculate a predicted cost for the migration configuration. The predicted cost may include the cost of migrating the service from the source platform to the destination platform as well as operational costs of hosting the service on the destination platform over time. For example, the metrics calculated based on the received operations data may include an average amount of data transmitted to and from the service to be migrated for a billing period. Based on this information (and other such information), the system may calculate a predicted cost for the service to be migrated to the destination platform. According to some embodiments, the cost may also include a cost of power, compute/network resources, or other factors of an on-premise data-center. 
     In conventional systems, an accurate calculation of the cost of a migration is difficult to calculate because there was no access to this type of operations data. According to various embodiments of the subject technology, a more accurate calculation of the cost of migration can be obtained because the system is able to collect information regarding how much data is transmitted to and from a service. Because multiple services may reside on a single host entity, conventional systems were not able to accurately detect and collect this information. For example, embodiments of the subject technology are able to track data transmitted to and from one service (e.g., a web application) on a host entity to another service (e.g., a backend database application) residing on the same host entity. This data flow would not occur in the network and thus would not be visible to some implementations. However, the sensors discussed with respect to the embodiments of the subject technology are able to detect and monitor data flows such as these. 
     At operation  425 , the system may provide the predicted cost for the migration configuration to the network administrator. For example, the system may provide a user interface accessible via the network for the network administrator view the predicted cost and other information relating to the migration configuration. For example, the system may also calculate a cost for a second configuration, generate a comparison between the cost of the first configuration and the second configuration, and provide the comparison to the user. The second configuration can be, for example, a current or existing configuration on the source platform or another configuration option. In some embodiments, the actual cost of operation of the current or existing configuration may be compared to the predicted cost for the migration configuration. The system may also provide a recommended configuration for a migration based on the predicted costs and comparisons of the costs. 
     In some cases, the migration of one or more services from an initial configuration to a second configuration may affect the performance of the services in ways that can be hard to predict. For example, moving services that may be collocated on the same host machine or in the same geographical location to another location of a destination host platform may introduce latency into the operations of the services. This increased latency may further cause additional operational effects (e.g., increased timeout events, etc.). In other cases, performance may be improved based on, for example, increased capabilities of the destination platform and/or moving services closer to other services that interact with the migrated services in order to reduce latency. 
     According to some embodiments, the system may further calculate one or more performance metrics based on the operations data, generated metrics, and the platform data. The performance metrics for the source platform and/or the existing configuration may be compared to the performance metrics for the destination platform and/or the migration configuration. The performance metrics and/or the comparison may be provided to a network administrator. Furthermore, the performance metrics and/or the comparison may be used to select a recommended migration configuration. This information may be valuable for resource planning and setting performance expectations. 
       FIG. 5A  and  FIG. 5B  illustrate systems in accordance with various embodiments. The more appropriate system will be apparent to those of ordinary skill in the art when practicing the various embodiments. Persons of ordinary skill in the art will also readily appreciate that other systems are possible. 
       FIG. 5A  illustrates an example architecture for a conventional bus computing system  500  wherein the components of the system are in electrical communication with each other using a bus  505 . The computing system  500  can include a processing unit (CPU or processor)  510  and a system bus  505  that may couple various system components including the system memory  515 , such as read only memory (ROM) in a storage device  520  and random access memory (RAM)  525 , to the processor  510 . The computing system  500  can include a cache  512  of high-speed memory connected directly with, in close proximity to, or integrated as part of the processor  510 . The computing system  500  can copy data from the memory  515  and/or the storage device  530  to the cache  512  for quick access by the processor  510 . In this way, the cache  512  can provide a performance boost that avoids processor delays while waiting for data. These and other modules can control or be configured to control the processor  510  to perform various actions. Other system memory  515  may be available for use as well. The memory  515  can include multiple different types of memory with different performance characteristics. The processor  510  can include any general purpose processor and a hardware module or software module, such as module  1   532 , module  2   534 , and module  3   536  stored in storage device  530 , configured to control the processor  510  as well as a special-purpose processor where software instructions are incorporated into the actual processor design. The processor  510  may essentially be a completely self-contained computing system, containing multiple cores or processors, a bus, memory controller, cache, etc. A multi-core processor may be symmetric or asymmetric. 
     To enable user interaction with the computing system  500 , an input device  545  can represent any number of input mechanisms, such as a microphone for speech, a touch-protected screen for gesture or graphical input, keyboard, mouse, motion input, speech and so forth. An output device  535  can also be one or more of a number of output mechanisms known to those of skill in the art. In some instances, multimodal systems can enable a user to provide multiple types of input to communicate with the computing system  500 . The communications interface  540  can govern and manage the user input and system output. There may be no restriction on operating on any particular hardware arrangement and therefore the basic features here may easily be substituted for improved hardware or firmware arrangements as they are developed. 
     Storage device  530  can be a non-volatile memory and can be a hard disk or other types of computer readable media which can store data that are accessible by a computer, such as magnetic cassettes, flash memory cards, solid state memory devices, digital versatile disks, cartridges, random access memories (RAMs)  525 , read only memory (ROM)  520 , and hybrids thereof. 
     The storage device  530  can include software modules  532 ,  534 ,  536  for controlling the processor  510 . Other hardware or software modules are contemplated. The storage device  530  can be connected to the system bus  505 . In one aspect, a hardware module that performs a particular function can include the software component stored in a computer-readable medium in connection with the necessary hardware components, such as the processor  510 , bus  505 , output device  535 , and so forth, to carry out the function. 
       FIG. 5B  illustrates an example architecture for a conventional chipset computing system  550  that can be used in accordance with an embodiment. The computing system  550  can include a processor  555 , representative of any number of physically and/or logically distinct resources capable of executing software, firmware, and hardware configured to perform identified computations. The processor  555  can communicate with a chipset  560  that can control input to and output from the processor  555 . In this example, the chipset  560  can output information to an output device  565 , such as a display, and can read and write information to storage device  570 , which can include magnetic media, and solid state media, for example. The chipset  560  can also read data from and write data to RAM  575 . A bridge  580  for interfacing with a variety of user interface components  585  can be provided for interfacing with the chipset  560 . The user interface components  585  can include a keyboard, a microphone, touch detection and processing circuitry, a pointing device, such as a mouse, and so on. Inputs to the computing system  550  can come from any of a variety of sources, machine generated and/or human generated. 
     The chipset  560  can also interface with one or more communication interfaces  590  that can have different physical interfaces. The communication interfaces  590  can include interfaces for wired and wireless LANs, for broadband wireless networks, as well as personal area networks. Some applications of the methods for generating, displaying, and using the GUI disclosed herein can include receiving ordered datasets over the physical interface or be generated by the machine itself by processor  555  analyzing data stored in the storage device  570  or the RAM  575 . Further, the computing system  500  can receive inputs from a user via the user interface components  585  and execute appropriate functions, such as browsing functions by interpreting these inputs using the processor  555 . 
     It will be appreciated that computing systems  500  and  550  can have more than one processor  510  and  555 , respectively, or be part of a group or cluster of computing devices networked together to provide greater processing capability. 
     For clarity of explanation, in some instances the various embodiments may be presented as including individual functional blocks including functional blocks comprising devices, device components, steps or routines in a method embodied in software, or combinations of hardware and software. 
     In some embodiments the computer-readable storage devices, mediums, and memories can include a cable or wireless signal containing a bit stream and the like. However, when mentioned, non-transitory computer-readable storage media expressly exclude media such as energy, carrier signals, electromagnetic waves, and signals per se. 
     Methods according to the above-described examples can be implemented using computer-executable instructions that are stored or otherwise available from computer readable media. Such instructions can comprise, for example, instructions and data which cause or otherwise configure a general purpose computer, special purpose computer, or special purpose processing device to perform a certain function or group of functions. Portions of computer resources used can be accessible over a network. The computer executable instructions may be, for example, binaries, intermediate format instructions such as assembly language, firmware, or source code. Examples of computer-readable media that may be used to store instructions, information used, and/or information created during methods according to described examples include magnetic or optical disks, flash memory, USB devices provided with non-volatile memory, networked storage devices, and so on. 
     Devices implementing methods according to these disclosures can comprise hardware, firmware and/or software, and can take any of a variety of form factors. Typical examples of such form factors include laptops, smart phones, small form factor personal computers, personal digital assistants, rackmount devices, standalone devices, and so on. Functionality described herein also can be embodied in peripherals or add-in cards. Such functionality can also be implemented on a circuit board among different chips or different processes executing in a single device, by way of further example. 
     The instructions, media for conveying such instructions, computing resources for executing them, and other structures for supporting such computing resources are means for providing the functions described in these disclosures. 
     Although a variety of examples and other information was used to explain aspects within the scope of the appended claims, no limitation of the claims should be implied based on particular features or arrangements in such examples, as one of ordinary skill would be able to use these examples to derive a wide variety of implementations. Further and although some subject matter may have been described in language specific to examples of structural features and/or method steps, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to these described features or acts. For example, such functionality can be distributed differently or performed in components other than those identified herein. Rather, the described features and steps are disclosed as examples of components of systems and methods within the scope of the appended claims.