Our BTS is going to need an accurate clock source in order to run, so without access to crazy accurate Timing over Packet systems or TDM links to use as reference sources, I’ve opted to use the GPS/GLONASS receiver built into the LMPT card. Add new GPS with ID 0 on LMPT in slot 7 […]
A look at how Cell Broadcast is signalling implemented between the MME and CBC in an LTE/EPC network.
This post is one in a series documenting my adventures attempting to configure a used BTS 3900 to function as a eNB in my lab. There are 5 network ports on the LMPT card: 2x SFP cages – SFP 0 and SFP 1 1x 10/100 Ethernet port – ETH – Used to access the Local […]
Learning Huawei’s flavour of MML – Man Machine Language for the BTS 3900 series Macro Base Stations.
Picking and validating antenna selection for the new RAN project in my lab.
How I ended up with a Macro LTE eNodeB (Huawei BBU3900) and getting it running.
Basic processes and functions of the LTE EPC Serving Gateway (S-GW).
Using Wireshark to filter S1 messaging to find signalling from a specific subscriber,
List of Open Source Evolved Packet Core implementations
What’s the deal with Tunnel Endpoint Identifiers and what do they do?
Using SDR hardware to view the LTE System Information Block’s contents.
Why the BaiCells PLMN changes?
A look into the signalling messages between Network elements in an Evolved Packet Core exchanged during the Attach Procedure
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 […]
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.
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. […]
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 […]
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 […]
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 […]
Sending SMS over LTE using OsmoMSC and OsmoHLR and the SGs interface for SMSoS