Expanded ON_CHANGE support for LLDP telemetry data through Junos Telemetry Interface (JTI)

OpenConfig support through remote procedure calls (gRPC) and JTI is expanded to support additional ON_CHANGE support for LLDP telemetry sensors. Periodical streaming of OpenConfig operational states and counters collects information at regular intervals. ON_CHANGE support streams operational states as events (only when there is a change), and is preferred over periodic streaming for time-sensitive missions. 

When you create a subscription using a top-level container as the resource path (for example, /lldp), a leaf under the resource path /lldp with ON_CHANGE support is automatically streamed based on events. If a leaf under the resource path does not have ON_CHANGE support, it will not be streamed. 

These paths, previously supporting periodical streaming only, now also support ON_CHANGE streaming: 

•  /lldp/state/enabled 
•  /lldp/state/chassis-id 
•  /lldp/state/chassis-id-type 
•  /lldp/state/system-name 
•  /lldp/state/system-description 
•  /lldp/state/hello-timer 
•  /lldp/interfaces/interface/state/name 
•  /lldp/interfaces/interface/state/enabled 
•  /lldp/interfaces/interface/neighbors/neighbor/state/chassis-id 
•  /lldp/interfaces/interface/neighbors/neighbor/state/chassis-id-type 
•  /lldp/interfaces/interface/neighbors/neighbor/state/port-id 
•  /lldp/interfaces/interface/neighbors/neighbor/state/port-id-type 
•  /lldp/interfaces/interface/neighbors/neighbor/state/port-description 
•  /lldp/interfaces/interface/neighbors/neighbor/state/system-name 
•  /lldp/interfaces/interface/neighbors/neighbor/state/system-description 
•  /lldp/interfaces/interface/neighbors/neighbor/state/management-address 
•  /lldp/interfaces/interface/neighbors/neighbor/state/management-address-type 
•  /lldp/interfaces/interface/neighbors/neighbor/capabilities 

These resource paths from the preceding list do not change with an event, but will be streamed on creation and deletion: 

•  /lldp/interfaces/interface/neighbors/neighbor/state/chassis-id 
•  /lldp/interfaces/interface/neighbors/neighbor/state/chassis-id-type 
•  /lldp/interfaces/interface/neighbors/neighbor/state/system-name 

Before events are streamed, there is an initial stream of states to the collector, followed by an END_OF_INITIAL_SYNC. This notice signals the start of event streaming.