This read-write integer sets the Fixed Round-Trip Time (FRTT), in milliseconds, for a standard ABR connection - the known or estimated fixed propagation round-trip delay used by the ABR rate-control algorithm - with a value of 0 explicitly meaning this figure isn't available. Admins configure this based on the actual known network path delay for the connection so ABR's feedback-loop timing calculations are accurate. For example, a long-haul ABR connection with substantial propagation delay would have a correspondingly higher ausmStdABRFRTT configured than a short local connection, affecting how the ABR algorithm paces its rate adjustments.