User Manual

Table Of Contents
Chapter 4 - Operation and Administration
BreezeACCESS VL System Manual
184
C or higher. In the AU, the concatenation process is performed separately for
each destination SU.
NOTE
Using the Link Capability exchange mechanism, each unit learns the HW Revision and the SW
Version of the unit(s) associated with it. A concatenated frame with a length exceeding 2200 bytes
may be generated and transmitted only if both the source and destination units have HW Revision
C or higher. If either the source or destination unit uses SW Version 3.0 or 3.1, then the maximum
size of the concatenated frame is 3400 bytes, and the maximum number of data frames that can be
bundled into a concatenated frame is 2 for units with SW version 3.0 and 8 for units with SW
version 3.1.
A frame is a candidate for bundling into a concatenated frame if all the following
conditions are met:
The frame is a data frame
The destination is an entity behind the destination AU/SU.
The destination AU/SU can support the feature (uses SW version 3.0 or
higher).
When a frame is identified as an eligible candidate for concatenation, it is marked
accordingly and will be processed according to the following:
If there is no concatenated frame designated to the same destination unit in
the queue:
If the hardware queue is empty – the frame is transmitted immediately.
Otherwise (the queue is not empty) – the frame is inserted to the queue as
a concatenated frame.
If a concatenated frame designated to the same destination unit exists in the
queue:
If the combined size of both frames is above the maximum allowed
concatenated frame size – both frames are transmitted as two separate
frames.
Otherwise (the combined frames size is below the maximum size) – the
new frame is added to the concatenated frame. If the number of data
frames in the concatenated frame has reached the maximum allowed
(applicable only if the destination unit uses SW version 3.0 or 3.1) – the
concatenated frame will be transmitted to the wireless medium. Otherwise
– the concatenated frame remains in the queue (until the hardware queue
becomes free).