Categories
EPC EUTRAN LTE Mobile Networks

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

Why the BaiCells PLMN changes?

Categories
EPC EUTRAN LTE Mobile Networks RFCs & Standards

LTE UE Attach Procedures in Evolved Packet Core (EPC)

A look into the signalling messages between Network elements in an Evolved Packet Core exchanged during the Attach Procedure

Categories
EUTRAN LTE Mobile Networks RFCs & Standards Voice over IP

Diameter and SIP: Registration-Termination-Request / Answer

These posts focus on the use of Diameter and SIP in an IMS / VoLTE context, however these practices can be equally applied to other networks. The Registration-Termination Request / Answer allow a Diameter Client (S-CSCF) to indicate to the HSS (Diameter Server) that it is no longer serving that user and the registration has […]

Categories
EPC LTE Mobile Networks RFCs & Standards Voice over IP

Diameter and SIP: User-Authorization-Request/Answer

The Diameter User-Authorization-Request and User-Authorization-Answer commands are used as the first line of authorization of a user and to determine which Serving-CSCF to forward a request to.

Categories
EPC LTE Mobile Networks RFCs & Standards Voice over IP

Diameter and SIP: Server-Assignment-Request/Answer

These posts focus on the use of Diameter and SIP in an IMS / VoLTE context, however these practices can be equally applied to other networks. The Server-Assignment-Request/Answer commands are used so a SIP Server can indicate to a Diameter server that it is serving a subscriber and pull the profile information of the subscriber. […]

Categories
EPC LTE Mobile Networks RFCs & Standards Voice over IP

Diameter and SIP: Location-Info-Request / Answer

These posts focus on the use of Diameter and SIP in an IMS / VoLTE context, however these practices can be equally applied to other networks. The Location-Information-Request/Answer commands are used so a SIP Server query a Diameter to find which P-CSCF a Subscriber is being served by Basics: The RFC’s definition is actually pretty […]

Categories
EPC LTE Mobile Networks RFCs & Standards

Diameter and SIP: Multimedia-Authentication-Request/Answer

These posts focus on the use of Diameter and SIP in an IMS / VoLTE context, however these practices can be equally applied to other networks. The Multimedia-Authentication-Request/Answer commands are used to Authenticate subscribers / UAs using a variety of mechanisms such as straight MD5 and AKAv1-MD5. Basics: When a SIP Server (S-CSCF) receives a […]

Categories
EPC LTE Mobile Networks

Connecting any 3rd Party HSS to Open5GS MME

Connecting an external / 3rd party HSS to Open5GS

Categories
GSM Mobile Networks

GSM with Osmocom: NanoBTS

Setting up ipaccess NanoBTS on Osmocom’s OsmoBSC

Categories
EUTRAN LTE Mobile Networks

srsLTE Install for BladeRF & LimeSDR on Debian / Ubuntu

Note: I’m running version 19.12.0 which I installed from the repos due to issues with 20.4.0 (latest when I wrote this) and stability on LimeSDR. I wrote the other day about installing SRS LTE stack, But installing it is one thing, meeting all the requirements to use it with your SDR hardware turns out to […]

Categories
EPC EUTRAN GSM LTE Mobile Networks

Sending SMS in Open5GS LTE Networks using the SGs Interface and OsmoMSC with SMSoS

Sending SMS over LTE using OsmoMSC and OsmoHLR and the SGs interface for SMSoS

Categories
EPC EUTRAN GSM LTE Mobile Networks

OsmoMSC and Open5GS MME – SGs Interface for CSCF / InterRAT Handover

Looking into the SGi interface for Circuit Switched Fallback in LTE to use GSM/UMTS networks for Calls & SMS

Categories
GSM Mobile Networks Voice over IP

GSM with Osmocom: Call routing in GSM

How call routing in GSM works and it’s application in the Osmocom suite

Categories
GSM Mobile Networks RF

GSM with Osmocom Part 9: Calls & SMS at last!

So now we’ve covered the basics of what’s involved let’s get some traffic on our network. For starters we’ll need to start each of our network elements and bring up whichever BTS hardware we’re using. In order for our calls to have audio, we’ll need to set a parameter on the Media Gateway. We’ll cover […]

Categories
GSM Mobile Networks

GSM with Osmocom Part 8: The Mobile Switching Center

Setting up the Mobile Switching Centre for a GSM network using OsmoMSC.

Categories
GSM Mobile Networks

GSM with Osmocom Part 7: The HLR – Home Location Register (and Friends)

What the Home Location Register (HLR) does in GSM, how to set it up and configure subscribers.

Categories
GSM Mobile Networks

GSM with Osmocom Part 6: Integrating our LimeSDR BTS with OsmoBSC

Connecting our LimeSDR based GSM BTS with OsmoBSC.

Categories
GSM Mobile Networks

GSM with Osmocom Part 5: Software BTS with LimeSDR & osmo-bts-trx

Using a LimeSDR as a GSM BTS with Osmocom.

Categories
GSM Mobile Networks

GSM with Osmocom Part 4: The Base Station Controller (BSC)

Configuring a GSM Base Station Controller with Osmocom stack.

Categories
GSM Mobile Networks

GSM with Osmocom Part 3: Introduction to Osmo Software & Virtual BTS

Setting up a virtual BTS in our BSC with Osmocom.