Streaming telemetry is the latest advancement in the world of metrics collection. It is so latest that even Wikipedia doesn't have an article on it. There is no clear technology stack at the core of telemetry.
Usually, behind the words telemetry there is a standard from Openconfig, but there are also implementations from juniper, huawei, cisco, arista (insert your vendor)...
/junos/system/linecard/firewall/
/junos/system/linecard/interface/
/junos/system/linecard/interface/logical/family/ipv4/usage/
/junos/system/linecard/interface/logical/family/ipv6/usage/
/junos/system/linecard/interface/logical/usage/
/junos/system/linecard/interface/queue/
/junos/system/linecard/npu/memory/
/junos/system/linecard/npu/utilization/
/junos/system/linecard/optics/