Tag Archives: BaiCells

BaiCells USIM PLMN Issues (MCC 314 / MNC 030 vs MCC 311 / MNC 98)

If you’re using BaiCells hardware you may have noticed the new eNBs and USIMs are shipping with the PLMN of MCC 314 / MNC 030.

First thing I do is change the PLMN, but I was curious as to why the change.

It seems 314 / 030 was never assigned to BaiCells to use and when someone picked this up they were forced to change it.

The MCC (Mobile Country Code) part is dictated by the country / geographic area the subscribers’ are in, as defined by ITU, whereas the MNC (Mobile Network Code) allocation is managed by the regional authority and ITU are informed as to what the allocations are and publish in their bulletins.

ITU advertised this in Operational Bulletin No. 1198 (15.VI.2020)

What does this mean if you’re a BaiCells user?

Well, SIM cards will have a different IMSI / PLMN, but the hardware supports Multi-Operator Core Network which allows one eNB to broadcast multiple PLMNs, so if you update your eNB it can broadcast both!

I’ve written more about that in my post on MOCN.

Multi Operator Core-Networks (MOCN) for RAN Sharing

MOCN is one of those great concepts I’d not really come across,

Multi-tenancy on the RAN side of the network, allowing an eNB to broadcast multiple PLMN IDs (MCC/MNC) in the System Information Block (SIB).

It allows site sharing not just on the tower itself, but site sharing on the RAN side, allowing customers of MNO A to see themselves connected to MNO A, and customers from MNO B see themselves as connected to MNO B, but they’re both connected to the same RAN hardware.

Setup in my lab was a breeze; your RAN hardware will probably be different.

In terms of signaling it’s a standard S1AP Setup Request except with multiple broadcast PLMN keys:

Now when I run a manual cell selection on my UE I can see the PLMN 460/11 as well as the Open5gs 00101 PLMN:

BaiCells Neutrino eNB Setup

For my LTE lab I got myself a BaiCells Neutrino, it operates on Band 3 (FDD ~1800Mhz) with only 24dBm of output power max and PoE powered it works well in a lab environment without needing -48vDC supply, BBUs, DUs feeders and antennas.

Setup can be done via TR-069 or via BaiCells management server, for smaller setups the web UI makes setup pretty easy,

Logging in with admin/admin to the web interface:

We’ll select Quick Settings, and load in our MME IP address, PLMN (MCC & MNC), Tracking Area Code, Cell ID and Absolute Radio Frequency No.

Once that’s done we’ll set our Sync settings to use GPS / GNSS (I’ve attached an external GPS Antenna purchased cheaply online).

Finally we’ll set the power levels, my RF blocking setup is quite small so I don’t want excess power messing around with it, so I’ve dialed the power right back:

And that’s it, it’ll now connect to my MME on port 36412 on SCTP.