Dear experts, We are trying to connect an osmocom platform to an Ericsson platform, and are trying to make funtional 2G. We use a VM for OSMO-BSC, a VM for OSMO-BTS-TRX + OSMO-PCU, and a Raspberry PI (trx-lms) Concerning the Gb, we connected the OSMO-PCU to an MKX Ericsson, and we have an error at the NS setup step.

The communication between the SGSN Ericsson and the OSMO-PCU seems ok (IP / routing OK) We hope that the Ericsson MKX SGSN is well configured.

We can see some packets: OSMO-PCU ---> SGSN : NS_RESET, Cause: P&M intervention, NS VCI: 0x1388, NSEI: 5000 and a response from the SGSN: NS_STATUS, Cause PROTOCOL ERROR - unspecified.

What could be the problem ? timers ? ns-vci, nsvc 1, encapsulation,... Did someone test this: OSMOCOM with an ERICSSON SGSN ?

One point is that the nsvci is only defined on the BSC (not on the SGSN)

Many thanks in advance, Best regards Hoping that you could help us

Jean-Marc ----------------------- BSC CONFIGURATION ----------------------- bts 0 type osmo-bts description LimeSDR Based BTS band GSM900 cell_identity 41023 location_area_code 390 base_station_id_code 63 ms max power 15 cell reselection hysteresis 4 rxlev access min 0 radio-link-timeout 32 channel allocator mode chan-req ascending channel allocator mode assignment ascending channel allocator mode handover ascending channel allocator mode vgcs-vbs ascending rach tx integer 9 rach max transmission 7 rach max-delay 63 channel-description attach 1 channel-description bs-pa-mfrms 5 channel-description bs-ag-blks-res 1 no nch-position no access-control-class-ramping early-classmark-sending forbidden early-classmark-sending-3g allowed ipa unit-id 901 0 oml ipa stream-id 255 line 0 neighbor-list mode automatic codec-support fr gprs ns timer tns-block 3 gprs ns timer tns-block-retries 3 gprs ns timer tns-reset 3 gprs ns timer tns-reset-retries 3 gprs ns timer tns-test 30 gprs ns timer tns-alive 3 gprs ns timer tns-alive-retries 10 gprs nsei 5000 gprs nsvc 0 nsvci 5000 gprs nsvc 0 local udp port 23001 gprs nsvc 0 remote ip 172.20.168.220 gprs nsvc 0 remote udp port 2157 ... ----------------------- PCU CONFIGURATION ----------------------- ns timer tns-block 3 timer tns-block-retries 3 timer tns-reset 3 timer tns-reset-retries 3 timer tns-test 30 timer tns-alive 3 timer tns-alive-retries 10 timer tsns-prov 3 timer tsns-size-retries 3 timer tsns-config-retries 3 timer tsns-procedures-retries 3 pcu flow-control-interval 10 cs 2 cs max 4 cs threshold 10 33 cs downgrade-threshold 200 cs link-quality-ranges cs1 6 cs2 5 8 cs3 7 13 cs4 12 mcs link-quality-ranges mcs1 6 mcs2 5 8 mcs3 7 13 mcs4 12 15 mcs5 14 17 mcs6 16 18 mcs7 17 20 mcs8 19 24 mcs9 23 mcs max 9 window-size 64 0 queue idle-ack-delay 10 queue codel