Project

General

Profile

Bug #1789

Issue with Long Run 1 - incorrect handling of EGPRS Ack/Nack

Added by arvind.sirsikar over 2 years ago. Updated about 2 years ago.

Status:
Closed
Priority:
High
Target version:
-
Start date:
08/09/2016
Due date:
% Done:

0%

Spec Reference:

Description

There are two major issues found when we recieve EGPRS Ack/Nack without "ACKNACK Dissector length" field in it.

1) CSN1 decoder doesn't decode the values properly.
2) gprs_rlcmac_dl_tbf::update_window function is not written according to 9.1.8.2.4 of 44.060.

Simulated Example(hex dump is captured in real OTA testing):

VA VS.
EPDAN received is "40 20 b ff d1 61 0 3e e 51 9f ff ff fb 80 0 0 0 0 0 0 0 0"

causes wrong decoding at CSN1along with error print in PCU as

[[0;m^M[[0;33m<0002> tbf_dl.cpp:388 - ack range is out of V(A) = 1176 ..V(S) = 1288 range TBF Free TBF! num_blocks = 113 dist = 2047 behind_last_bsn = 1289 first_bsn = 1176

Refer issue 2 above: When EPDAN is reported with out of window the status of bsns out of the window needs to be ignored. But in current implementation of gprs_rlcmac_dl_tbf::update_window it is not honored and DL TBF is getting freed causing instability in DL traffic.

History

#1 Updated by arvind.sirsikar about 2 years ago

fixed in PCU commit

fb41afaaf69f1abeb56b1d95c0c707448e209b70

#2 Updated by arvind.sirsikar about 2 years ago

  • Status changed from New to Closed

Also available in: Atom PDF

Add picture from clipboard (Maximum size: 48.8 MB)