  Rather than directly considering the queuing delay of data, this memo focuses
on reducing the delay that congestion signals experience within a queue
management algorithm, which can be greater than the delay that the data itself
experiences within the queue. Once the congestion signals are delayed,
regulation of the load becomes more sloppy, and the queue tends to overshoot
and undershoot more as a result, leading the data itself to experience greater
peaks in queuing delay as well as intermittent under-utilization. Where the
service rate of a queue varies, it is preferable to measure the queue in units
of time not bytes. However, the size of the queued backlog can be measured in
bytes and signalled at the last instant as data leaves the queue, whereas
measuring queuing delay introduces inherent delay. This paper proposes 'scaled
sojourn time', which scales queuing delay by the ratio between the backlogs at
dequeue and enqueue. This is equivalent to scaling the sojourn time by the
ratio of the arrival and departure rates averaged over the time spent in the
queue. The paper also proposes the removal of delays due to randomness in the
signal encoding.
