| commit | db56a3563e3d76f75613581b666390c4ceddbc3d | [log] [tgz] |
|---|---|---|
| author | Vadim Yanitskiy <vyanitskiy@sysmocom.de> | Sat Aug 22 02:05:28 2020 +0700 |
| committer | Vadim Yanitskiy <vyanitskiy@sysmocom.de> | Tue Sep 08 02:47:02 2020 +0700 |
| tree | d5dff5206ccd9c95cb1af9db15519ec154418a36 | |
| parent | 962d717f41cf70c08f881268c367fe0a5b8c9d7e [diff] |
encoding: use CSN.1 codec to generate Packet Uplink Assignment
It's quite odd to see that in write_packet_downlink_assignment()
we initialize an 'RlcMacDownlink_t', so then the caller can use
the power of CSN.1 codec to generate the final sequence of bytes
to be transmitted, while in write_packet_uplink_assignment() we
already compose the final RLC/MAC message straight away using
the low-level bitvec API (like bitvec_write_field()).
I guess the reason is that at the time of writing this code, the
CSN.1 codec was not stable enough, so it was safer to generate
the message 'by hand'. This would also explain why we *decode*
the final RLC/MAC message in create_ul_ass() right after encoding.
Rewrite write_packet_uplink_assignment(), so now it initializes
a caller-provided 'RlcMacDownlink_t' structure. Given that it's
allocated on heap using talloc_zero(), do not initialize presence
indicators of fields that are not present in the message.
This would facilitate handling of frequency hopping parameters
in the upcoming changes, in particular we can now introduce a
function that would compose Frequency Parameters IE for both
write_packet_{downlink,uplink}_assignment().
Tested manually by running a GPRS-enabled network, as well as by
running test cases from ttcn3-pcu-test => no regressions observed.
Change-Id: I2850b91e0043cdca8ae7498a5fc727eeedd029b6
Related: SYS#4868, OS#4547
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
The official homepage of the project is https://osmocom.org/projects/osmopcu/wiki/OsmoPCU
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/
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.
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.
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