A method performed by a network device along a data path for real-time network-wide link latency monitoring. The method includes receiving a packet; incrementing a packet counter; determining whether the packet counter is at least equal to a silent period value (M) when a sampling cycle flag is not set; determining whether the packet includes an existing in-band network telemetry (INT) header when the packet counter is at least equal to the silent period value (M); inserting INT data into the existing INT header of the packet and setting the sampling cycle flag when the packet includes the existing INT header; and forwarding the packet along a data path towards a destination device.