vOLT Service

The vOLT Service is responsible for configuring and managing access networks (OLT and ONU devices and the associated PON network) and does so by leveraging VOLTHA.

Models

Below is a diagram describing the models that comprise this service, followed by a brief description of them. For a full reference on these models, please take a look at their xProto representation.

ER Diagram

  • VOLTService. Contains information that the synchronizer needs to access VOLTHA and ONOS-VOLTHA
    • voltha_url, voltha_port. Hostname and port of VOLTHA endpoint.
    • voltha_user, voltha_pass. Username and password for VOLTHA.
    • onos_voltha_url, onos_voltha_port. Hostname and port of ONOS associated with VOLTHA.
    • onos_voltha_user, onos_voltha_pass. Username and password for ONOS.
  • vOLTServiceInstance. Extends ServiceInstance, and holds the OLT subscriber-related state for the service chain.
    • description. Description of the service instance.
    • onu_device. Relation to an ONUDevice object.
  • OLTDevice. Represents an OLT Device. Contains the information needed to pre-provision and activate the OLT.
    • volt_service. Relation to the VOLTService that owns this OLT.
    • name. Name of device.
    • device_type. Type of device, defaults to openolt.
    • host, port. Hostname and port of OLT.
    • mac_address. MAC Address of OLT.
    • serial_number. Serial number of OLT.
    • device_id. VOLTHA device id.
    • admin_state.
    • oper_status.
    • of_id. Openflow ID.
    • dp_id. Datapath ID.
    • uplink. Uplink port.
    • driver. Driver, defaults to voltha.
    • switch_datapath_id, switch_port. Identifies the switch the OLT is attached to.
    • outer_tpid. Outer VLAN id field EtherType.
    • nas_id. Authentication ID (propagated to the free-radius server via sadis)
  • ONUDevice. Represents an ONU Device.
    • pon_port. Relation to a PONPort that connects this ONU to an OLT.
    • serial_number. Serial number of the ONU.
    • vendor. Vendor of the ONU.
    • device_type. Device type, defaults to asfvolt16_olt.
    • device_id. VOLTHA device id.
    • admin_state.
    • oper_status.
    • connect_status.
  • NNIPort, PONPort, PONONUPort, UNIPort. These represent various ports attached to OLTs and ONUs.

Example Tosca

These are examples are taken from the olt-service repository. See the samples folder for additional examples.

Create an OLT

tosca_definitions_version: tosca_simple_yaml_1_0
imports:
  - custom_types/oltdevice.yaml
  - custom_types/voltservice.yaml
description: Create a simulated OLT Device in VOLTHA
topology_template:
  node_templates:

    service#volt:
      type: tosca.nodes.VOLTService
      properties:
        name: volt
        must-exist: true

    device#olt:
      type: tosca.nodes.OLTDevice
      properties:
        name: test_olt
        device_type: ponsim
        host: 172.17.0.1
        port: 50060
        switch_datapath_id: of:0000000000000001
        switch_port: "1"
        outer_tpid: "0x8100"
        dp_id: of:0000000ce2314000
        uplink: "129"
      requirements:
        - volt_service:
            node: service#volt
            relationship: tosca.relationships.BelongsToOne

Add a PONPort and ONUDevice to an OLT

tosca_definitions_version: tosca_simple_yaml_1_0
imports:
  - custom_types/oltdevice.yaml
  - custom_types/onudevice.yaml
  - custom_types/ponport.yaml
  - custom_types/voltservice.yaml
  - custom_types/uniport.yaml
description: Create a simulated OLT Device in VOLTHA
topology_template:
  node_templates:

    device#olt:
      type: tosca.nodes.OLTDevice
      properties:
        name: test_olt
        must-exist: true

    pon_port:
      type: tosca.nodes.PONPort
      properties:
        name: test_pon_port_1
        port_no: 2
      requirements:
        - olt_device:
            node: device#olt
            relationship: tosca.relationships.BelongsToOne

    device#onu:
      type: tosca.nodes.ONUDevice
      properties:
        serial_number: BRCM1234
        vendor: Broadcom
      requirements:
        - pon_port:
            node: pon_port
            relationship: tosca.relationships.BelongsToOne

    uni_port:
      type: tosca.nodes.UNIPort
      properties:
        name: test_uni_port_1
        port_no: 2
      requirements:
        - onu_device:
            node: device#onu
            relationship: tosca.relationships.BelongsToOne

Integration with other Services

The western neighbor of the vOLT Service is typically the R-CORD Service, which handles subscriber-related state. The vOLT Service may pull subscriber related information, such as VLAN tags, ONU serial numbers, etc., from that service.

The eastern neighbor of the vOLT Service is typically the Fabric Crossconnect Service, which programs the aggregation switch to connect OLT traffic to the Internet. When a VOLTServiceInstance is created, the vOLT Service will create a ServiceInstance in its eastern neighbor to connect this traffic.

Synchronization Workflow

Push steps

There are two top-down steps in this service:

  • SyncOLTDevice to pre-provision and enable OLT devices. Also handles disabling and deleting the OLT from VOLTHA when the model is deleted in XOS.
  • SyncVOLTServiceInstance to add the subscriber in ONOS-VOLTHA

Pull steps

The vOLT synchronizer is currently pulling OLTDevice, PONPort, NNIPort and ONUDevices from VOLTHA. When these devices are created in VOLTHA, the corresponding objects will automatically be created in the XOS data model.

Event steps

The vOLT synchronizer is listening over the kafka bus for events in the xos.kubernetes.pod-details topic. These events are used to automatically re-push state to VOLTHA when VOLTHA containers are restarted.

Model Policies

The VOLTServiceInstance model policy will create an eastbound service instance. This is typically in a fabric-related service, such as the Fabric Crossconnect Service, and is responsible for connecting OLT/ONU traffic to the Internet. The model policy will leverage an acquire_service_instance() method in the eastbound service to create the eastbound service instance.