last activated cell/area SIM card

For DF ProSe look here

tech-invite.com

These opposing views still occur in todays CSP networks. Cases of people using their UE/MS quite less and bought them years ago lead the carriers to still accept the access into UMTS by SIMs to not bother customers. As cell-load is high on 3G/4G and up, carriers are kind of 'happy' having users still being limited into UMTS even they just use voice and messaging and no data services.

Another development brings these 'legacy users' into new USIMs. If buying new devices having smaller "SIM"-trays like iPhones they get pushed to replace their SIMs by getting appropriate USIMs (mini, micro, nano or tech. 2FF, 3FF, 4FF).

I was involved in an Iranian case and their SIMs by all carriers still run smoothly and do not get pushed back by no service in UMTS cells.

The problem on having multiple RAN mixed and multi-Gen cells on cell towers leads to more complexity as traffic offloading (mainly data and time-critically) are offloaded to either SmallCells (WiFi-based APs) or looming StreetConnect cells. But their it also depends on the carrier settings (baseband configs) to the UE/MS by setting up or after switching USIMs and getting new either silent or visible USSD-codes mostly still for MMS or browsing.

Conclusively I expect still cases having opposite views but good chance to view traffic LI-logs to see
if just was connected by drive-by and not traffic or actively running services e.g. voice.

Worthy to say, that manufacturers sometimes not fully mapp 3GPP TSs into their code running on Net Elements and controlled by their Network Management Systems (NMS).

Heavyly depends on the Mobile Network Operator (MNO).

This is excellent feedback; thank you Rolf the expert.

These opposing views still occur in todays CSP networks. Cases of people using their UE/MS quite less and bought them years ago lead the carriers to still accept the access into UMTS by SIMs to not bother customers. As cell-load is high on 3G/4G and up, carriers are kind of 'happy' having users still being limited into UMTS even they just use voice and messaging and no data services.

Yes, I can imagine that would be so as to avoid customer churn.

Another development brings these 'legacy users' into new USIMs. If buying new devices having smaller "SIM"-trays like iPhones they get pushed to replace their SIMs by getting appropriate USIMs (mini, micro, nano or tech. 2FF, 3FF, 4FF).

The iPhone card slot-in is small, but the amount of promotions by MNO/VMNO SIM Card only subscriptions and prepaid has risen in the UK so that users are retaining their legacy handsets. Also Samsung and other manufacturers haven't really joined iPhone model and really iPhone's ultra small card will be more of a frustration to customers who decide not to use iPhone handsets. If form-factor should have a global impact for manufacturers then I would imagine embedded UICC (eUICC) would be their choice. Problematical even with that though is people may not want to have to buy a handset/eUICC every time the user wishes to choose a different network to get another phone/eUICC.

I was involved in an Iranian case and their SIMs by all carriers still run smoothly and do not get pushed back by no service in UMTS cells.

Which is indicative then of evolution and development of techniques in mobile networks since 2001.

The problem on having multiple RAN mixed and multi-Gen cells on cell towers leads to more complexity as traffic offloading (mainly data and time-critically) are offloaded to either SmallCells (WiFi-based APs) or looming StreetConnect cells. But their it also depends on the carrier settings (baseband configs) to the UE/MS by setting up or after switching USIMs and getting new either silent or visible USSD-codes mostly still for MMS or browsing.

Talking of installations you may enjoy browsing through these documents created by the then Office of the Deputy Prime Minister (John Prescott) which I have from 11 years ago. The old ODPM website is no longer available. They are helpful documents defining the way forward with small cells vis-à-vis existing installations

https://www.dropbox.com/s/uibqptlha71t8g6/odpm_plan_606401.pdf?dl=0
https://www.dropbox.com/s/q4a4tvxb3ezgxos/odpm_plan_606402.pdf?dl=0
https://www.dropbox.com/s/jw0am28bnwbm0cc/odpm_plan_606403.pdf?dl=0
https://www.dropbox.com/s/vi6anpkkvxzc4vf/odpm_plan_606404.pdf?dl=0
https://www.dropbox.com/s/w9kj13xqotmmzvq/odpm_plan_606405.pdf?dl=0
https://www.dropbox.com/s/ox1hpfgoaq6wyks/odpm_plan_606406.pdf?dl=0

Conclusively I expect still cases having opposite views but good chance to view traffic LI-logs to see if just was connected by drive-by and not traffic or actively running services e.g. voice.

Given the laws and regulations in the UK the requirement of proportionality would need to be justified first before access to such logs may take place. Also, a cell site analysis is largely historical LI-logs wouldn't be available as the OIC would be dealing with mobile network past event.

Worthy to say, that manufacturers sometimes not fully mapp 3GPP TSs into their code running on Net Elements and controlled by their Network Management Systems (NMS).

Heavyly depends on the Mobile Network Operator (MNO).

Enjoyed the discussion , once again thanks Rolf.

Thank you for the dropb docs I will enjoy to study, the pleasure is on my side -)