Bug #4052
closed
- Related to Bug #3728: Problem using compressed ACK/NACK bitmaps or uncompressed bitmaps without length added
- Priority changed from Normal to Urgent
- Status changed from New to In Progress
- % Done changed from 0 to 20
There is at least one corner cases, which I'ven't found in the 44.060: What happens when an EGPRS ACK/NACK does not have a Length field, but the uncompressed RBB is less the remaining rest_bits? This was possible, when less than 8 bits were remaining, so only happens when having huge packet loss.
... This is defined as spec compliant. Out of window bits should be ignored.
I've implemented a fix for this in my branch lynxis/gprs-ack-nack https://gerrit.osmocom.org/plugins/gitiles/osmo-pcu/+/lynxis/gprs-ack-nack
I will push this patch to gerrit and write test cases for the encoding.
However I want also validate the encoding of the URBB is correct at all.
- Spec Reference set to 44.060
lynxis wrote:
There is at least one corner cases, which I'ven't found in the 44.060: What happens when an EGPRS ACK/NACK does not have a Length field, but the uncompressed RBB is less the remaining rest_bits? This was possible, when less than 8 bits were remaining, so only happens when having huge packet loss.
... This is defined as spec compliant. Out of window bits should be ignored.
But those bits are still within the window. They won't be ignored. And bits which represent V(R) or higher must be set to 0 (44.060 9.1.10).
- Status changed from In Progress to Feedback
- % Done changed from 20 to 90
- Status changed from Feedback to Closed
- % Done changed from 90 to 100
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