The jammed harbor helped explain the lack of upstream traffic.

The pool of usable channels is then split into two different frequency bands for upstream and downstream traffic, based on a preconfigured ratio.

The Blue Flagger watches upstream traffic for overtaking cars and displays the blue flag and other flags as required.

"If you're limiting upstream traffic, you're not going to see upstream traffic," Wade counters.

First, traffic proceeded by steamboat up to the Cascades, where rapids blocked the river to all upstream traffic and made downstream traffic extremely hazardous.

Or does it say, look, there's a lot of upstream traffic, kill it?

As there are separate sets of locks for upstream and downstream traffic, this system is more water efficient than bi-directional staircase locks.

Unless UDP is used, in which case there would be nearly 0% upstream traffic as no ACKs are required.

The only upstream traffic would be playback control.

They took a position near a small island, where they could keep themselves at least partly concealed to upstream traffic.