Osmocom Packet control Unit (PCU): Network-side GPRS (RLC/MAC); BTS- or BSC-colocated
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Minh-Quang Nguyen 1bcfa9aacf PCU: Fix TA adjustment
Promblem:
 TA provided from L1 PH-DATA-IND is a relative amount of TA adjustment to actual TA
 being used for given TBF. The current TA update algorithm in PCU simply applies the relative
 amount of TA to given TBF but does not take into account of current TA.
 As a result, the PCU will request wrong TA jump for given TBF if the MS is moving away from
 BTS more than 2 km.

 Related issue: http://osmocom.org/issues/2611

Fixes:
- The PCU needs increase or decrease current TA of given TBF on receiving of relative
  amount of TA adjustment provided by PH-DATA-IND from L1
- The PCU needs to set absolute TA of given TBF on receiving absolute TA provided by
  PH-RA-IND from L1.

Change-Id: I65212f8203f1a35278890f51db038d689b2493d5
2017-11-16 10:06:41 -05:00
contrib jenkins: use osmo-clean-workspace.sh before and after build 2017-10-30 04:22:10 +00:00
debian Tag/Release Version 0.4.0 2017-10-29 12:10:13 +01:00
examples Revert "pcu: Improve default config" 2015-11-30 12:11:48 +01:00
include Add pcu-socket vty config 2017-08-09 12:17:39 +02:00
src PCU: Fix TA adjustment 2017-11-16 10:06:41 -05:00
tests tests: Don't use private version of log_info but global gprs_log_info 2017-10-29 11:02:34 +01:00
.gitignore Ignore test binaries using mask 2017-07-10 10:49:02 +02:00
.gitreview add .gitreview 2016-05-19 06:39:45 +00:00
COPYING import GPLv2 license text to this project 2012-07-22 22:05:44 +02:00
Makefile.am Facilitate future releases 2017-08-24 13:53:25 +02:00
README.md README: Clarify that fixed allocations have been revmoved from 3GPP specs 2017-07-29 22:15:02 +02:00
TODO TODO: Update the todolist with some musings... 2014-01-16 10:11:57 +01:00
configure.ac Call osmo_init_logging() before static BTS constructor 2017-10-29 11:02:34 +01:00
git-version-gen Add auto-foo (partial cleanup, master makefile/configure.ac 2012-06-14 21:05:44 +08:00
osmo-pcu.pc.in Add pkg-config file 2017-03-09 12:17:35 +01:00
osmoappdesc.py Added conditional python-based tests for VTY/config handling 2013-04-06 11:00:20 +02:00

README.md

osmo-pcu - Osmocom Packet Control Unit

This repository contains a C/C++-language implementation of a GPRS Packet Control Unit, as specified by ETSI/3GPP. It is part of the Osmocom Open Source Mobile Communications project.

The Packet Control Unit is terminating the Layer 2 (RLC/MAC) of the GPRS radio interface and adapting it to the Gb Interface (BSSGP+NS Protocol) towards the SGSN.

The PCU interfaces with the physical layer of the radio interface. OsmoPCU is typically used co-located with the BTS, specifically OsmoBTS. For legacy BTSs that run proprietary sotware without an interface to OsmoPCU, you may also co-locate it with the BSC, specifically OsmoBSC

Homepage

The official homepage of the project is https://osmocom.org/projects/osmopcu/wiki/OsmoPCU

GIT Repository

You can clone from the official osmo-pcu.git repository using

git clone git://git.osmocom.org/osmo-pcu.git

There is a cgit interface at http://git.osmocom.org/osmo-pcu/

Documentation

We provide a user manual as well as a vty reference manual

Please note that a lot of the PCU configuration actually happens inside the BSC, which passes this configuration via A-bis OML to the BTS, which then in turn passes it via the PCU socket into OsmoPCU.

Mailing List

Discussions related to osmo-pcu are happening on the osmocom-net-gprs@lists.osmocom.org mailing list, please see https://lists.osmocom.org/mailman/listinfo/osmocom-net-gprs for subscription options and the list archive.

Please observe the Osmocom Mailing List Rules when posting.

Contributing

Our coding standards are described at https://osmocom.org/projects/cellular-infrastructure/wiki/Coding_standards

We us a gerrit based patch submission/review process for managing contributions. Please see https://osmocom.org/projects/cellular-infrastructure/wiki/Gerrit for more details

The current patch queue for osmo-pcu can be seen at https://gerrit.osmocom.org/#/q/project:osmo-pcu+status:open

Current limitations

  • No PFC support
  • No fixed allocation support (was removed from 3GPP Rel >= 5 anyway)
  • No extended dynamic allocation support
  • No unacknowledged mode operation
  • Only single slot assignment on uplink direction
  • No half-duplex class support (only semi-duplex)
  • No TA loop
  • No power loop