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Data Learning Engine API Overview


The Data Learning Engine (DLE) API enables access to the network analytics data collection functions of the DLE component of Juniper Networks Cloud Analytics Engine. DLE acts as an independent network entity to gather available analytics data about devices in the network, and analyzes, normalizes, and stores it in a consistent way.

Using the DLE RESTful APIs, you can access the following DLE capabilities to request network analysis data collection and receive collected data:

  • Application Flow Path Tracing:

    Set up end-to-end and per-hop network tracing and analytics data collection for both underlay and overlay application flow paths.

    DLE communicates with Cloud Analytics Engine Compute Agent (CA) components in the network to generate probes that emulate application traffic and collect flow data traces from the network devices in the flow path.

    Using the DLE flow path APIs, you can:

    • Get information about available CA components and choose which application flows to trace.

    • Request to start or stop application flow data trace collection, including encapsulated flows for underlay-overlay correlation.

    • Retrieve collected flow path trace data from DLE, including summary or detailed probe and hop data, and per-interface transmit and receive statistics.

  • Data Subscription Service:

    (Starting in Junos OS Release 14.1X53-D30) Subscribe to and automatically receive bulk flow path analytics data that DLE collects from network devices.

    DLE supports a flow path analytics data subscription service that publishes network analytics data to subscribed clients as it is collected, enabling clients to consume that data in real-time and avoid the overhead of periodic polling. You can configure DLE to enable or disable the subscription service by setting property (enabled) or false (disabled) in the DLE configuration file /opt/cae/dle/conf/ When subscribing, the client must be prepared to receive streamed UDP data that DLE publishes to the receiver port specified in the subscription request.

    Using the DLE data subscription APIs, you can:

    • Subscribe to and receive streamed CA flow path data collected by DLE for all currently active flows.

    • Unsubscribe and stop receiving streamed flow path data from DLE.

  • High-frequency Network Traffic Analysis (NTA) Statistics Sampling:

    Request NTA packet-based traffic sampling data collected by DLE.

    For network devices managed by Juniper Networks Network Director, you can enable NTA data monitoring as described in Configuring Network Traffic Analysis in the Network Director documentation. Network devices stream the NTA data to DLE, and DLE processes and stores the samples as application or conversation flow statistics.

    Using the DLE NTA APIs, you can:

    • Retrieve cumulative and top NTA application and conversation sample results from DLE based on specified options.

See Data Learning Engine RESTful API Quick Reference for a complete list of DLE RESTful APIs with quick reference links to their usage details.

In the general context of the analytics data that can be retrieved using DLE APIs:

  • A flow is represented by an N-tuple identifying the devices for which data is being collected.

    Specifically, this is the following 5-tuple:

    { source IP address, destination IP address, transport protocol, application source port, application destination port }

  • A tunnel represents an encapsulation type. The DLE API supports the VXLAN encapsulation type.

    A tunnel or encapsulated flow is minimally identified by its assigned VXLAN network identifier (vnid), VTEP source IP address, and VTEP destination IP address.

  • An NTA application is identified by the pair of values transport protocol and application port number.

  • An NTA conversation represents unidirectional information exchanged between two hosts. Bidirectional traffic is treated as two different conversations, one for each direction between the hosts. An NTA conversation is identified by the pair of values source IP address and destination IP address.

  • DLE reports only TCP and UDP Layer 3 traffic.


The default HTTP port for DLE is 8282, which can be changed using the DLE configuration file /opt/cae/dle/conf/