Cellular Network Infrastructure » Radio Access Network » OsmoPCU

Freeing the TBFs (so queued dat ais not continued to be sent) can be found here:
https://gerrit.osmocom.org/c/osmo-pcu/+/20245 Free all MS TBFs when receiving GPRS Suspension Request

So far I have been testing this locally by having 2 phones registered to a network and then doing an MO_MT call, and it's working fine.

Hi Pau,

The test should validate:

• A BSSGP SUSPEND is sent towards SGSN (and SUSPEND ACK is sent abck by it)

we already have TC_pcuif_suspend verifying this.

• All active TBFs are released (so for instance if some DL data is queued in PCU waiting to be sent to the MS, it is dropped after receiving the Suspend Request message).

Feel free to add a new test case for that, but let's please keep TC_pcuif_suspend unchanged. The question is how would you check if TBFs are actually released? Probably, VTY interface is the only reliable variant, but we can additionally check the counters.

It's easy:
1- Request UL TBF to PCU, get it and start sending UL rlcmac blocks
2- Send several RLCMAC DL blocks from SGSN, they are queued in osmo-pcu
3- PCUIF sends GPRS Suspension Request
4- Make sure no new data is received at PCUIF (because it's not scheduled because TBF was released). Try sending some data over PCUIF and check no data is received at SGSN (because there's no active TBF).

Test makin sure TBF is released has been added (passing) here:
https://gerrit.osmocom.org/c/osmo-ttcn3-hacks/+/22100 pcu: Introduce test TC_pcuif_suspend_active_tbf

Once merged we can close the ticket.

merged, closing.