Categories
EPC LTE Mobile Networks RFCs & Standards

Diameter – Insert Subscriber Data Request / Response

A look at how the HSS can update the profile of an already in-use subscription using Insert Subscriber Data Request/Response.

Categories
EPC LTE Mobile Networks SIM Cards

PS Data Off

How turning mobile data off, doesn’t, in LTE and 5G.

Categories
EPC Mobile Networks RFCs & Standards Voice over IP

Docker & BIND as an ENUM Playground

A Bind environment in a Docker container for experimenting and learning ENUM for DNS based Call Routing.

Categories
GSM LTE Mobile Networks RFCs & Standards

Looking inside the MMS Exchange (With call flow and PCAP)

A look at Multimedia Messaging (MMS) in 3GPP Networks and how it actually works.

Categories
EPC LTE Mobile Networks RFCs & Standards

Telephony binary-coded decimal (TBCD) in Python with Examples

Chances are if you’re reading this, you’re trying to work out what Telephony Binary-Coded Decimal encoding is. I got you. Again I found myself staring at encoding trying to guess how it worked, reading references that looped into other references, in this case I was encoding MSISDN AVPs in Diameter. How to Encode a number […]

Categories
5G SA EPC EUTRAN LTE Mobile Networks RFCs & Standards Security SIM Cards

The PLMN Problem for Private LTE / 5G

As the number of Private Networks built on LTE and 5G grow, how will PLMN allocation be managed?

Categories
EPC LTE Mobile Networks

How UEs get Time in LTE

How does “Network Time” actually get to the UE?

Categories
EPC LTE Mobile Networks

Diameter Agents

A look at the 4 types of Diameter Agent

Categories
EPC LTE Mobile Networks RFCs & Standards

SCTP Parameter Tuning

A look at tuning your SCTP parameters to detect failures quickly and reduce dropped packets when they happen.

Categories
5G SA EPC LTE Mobile Networks Voice over IP

IMS Routing with iFCs

Peer behind the magic curtain at how IMS networks route your VoLTE and VoNR calls, and how iFC (Initial Filter Criteria) achieve this.

Categories
5G SA EPC EUTRAN GSM LTE Mobile Networks RFCs & Standards

Pre-5G Network Slicing

5G introduces Network Slicing, or does it? A look at slicing mechanisms widely used in pre-5G networks.

Categories
EPC LTE Mobile Networks RFCs & Standards

Diameter Droplets – The Flow-Description AVP and IPFilterRules

Getting to know IPfilterRules and the Flow-Description AVP

Categories
EPC GSM LTE Mobile Networks RFCs & Standards

The Surprisingly Complicated world of MO SMS in IMS/VoLTE

Short messaging can be anything but simple…

Categories
5G SA EPC LTE Mobile Networks Software

Open5Gs Database Schema Change

New database time to support slicing and a migration path for existing users.

Categories
EPC Kamailio LTE Mobile Networks Software

A very unstable Diameter Routing Agent (DRA) with Kamailio

I’d been trying for some time to get Kamailio acting as a Diameter Routing Agent with mixed success, and eventually got it working, after a few changes to the codebase of the ims_diameter_server module. It is rather unstable, in that if it fails to dispatch to a Diameter peer, the whole thing comes crumbling down, […]

Categories
EPC LTE Mobile Networks Python Software

PyHSS Update – YAML Config Files

Introducing YAML based config files for defining how PyHSS should be setup

Categories
EPC LTE RFCs & Standards

MSISDN Encoding in Diameter AVPs – Brought to you by the letter F

Peculiar padding problem perplexes poor programmer.

Categories
EPC LTE Mobile Networks Python

PyHSS Update – SCTP Support

Info on PyHSS new support for SCTP as well as TCP.

Categories
5G SA EPC EUTRAN GSM LTE Mobile Networks RFCs & Standards Security

And the call was coming from… INSIDE THE HOUSE. A look at finding UE Locations in LTE

How to find a subscriber location within the network.

Categories
5G SA LTE Mobile Networks Python Security Software

PyHSS New Features

Thanks to some recent developments, PyHSS has had a major overhaul recently, and is getting better than ever, Some features that are almost ready for public release are: Config File Instead of having everything defined all over the place a single YAML config file is used to define how the HSS should function. SCTP Support […]