[isostatic]

Depends on the router, and the load. If you have a 100mbit uplink and 4x1 gig on the downlink side, you could easily have 10mbit of packets arrive in 3ms (70 packets per millisecond), but would take 30ms to send those packets. You can either

1) Drop -- despite total trafic being only 10mbit a second

2) Queue -- introducing a delay of 30ms.

In reality you'd put latency critical applications (voip etc) at the top of the queue so the pcakets get transmitted without the delay, and your facebook packets get delayed by 31ms rather than 30ms.