User's Manual

Horizon Compact Plus Release 1.0.1 Wireless Ethernet Product User Manual – Volume 2
9.0 Pause Frames
Pause frames are generated by the weaker (slower) link when its forward pipe gets full. Pause frames
inform the upstream device to “pause and stop sending traffic for a period of a specific ‘quanta’” (refer to
ieee 802.3 standard for the definition of ‘quanta’). When the Pause Frame feature is enabled, Horizon
Compact Plus generates pause frames to the Ethernet switch when the Horizon Compact Plus receiving
buffer hits the internally set threshold. The receiving buffer threshold is close to 100 msec at GigE rate.
At data rates lower than GigE, the data buffer will accommodate a lesser amount of data. The Pause
Frame feature cannot be used when CoS/QoS is enabled.
When the pause frame feature is enabled the system sends pause frames to an attached network
switch. If the system receives a pause frame it is sent transparently over the air to the other end of the
link. Pause frames are treated as slow bridge protocol frames (destination MAC 01-80-c2-00-xx-xx) and
the same QoS behavior is applied to them as slow bridge protocol frames (see Section 8.4.2.).
The pause frame feature can only be enabled on port p1 and is configured as part of set enet config
command (see Section 3.0).