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

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EPC GSM LTE Mobile Networks RFCs & Standards

The Surprisingly Complicated world of MO SMS in IMS/VoLTE

Since the beginning of time, SIP has used the 2xx responses to confirm all went OK. If you thought sending an SMS in a VoLTE/IMS network would see a 2xx OK response and then that’s the end of it, you’d be wrong. So let’s take a look into sending SMS over VoLTE/IMS networks! So our […]

Categories
5G SA EPC LTE Mobile Networks Software

Open5Gs Database Schema Change

As Open5Gs has introduced network slicing, which led to a change in the database used, Alas many users had subscribers provisioned in the old DB schema and no way to migrate the SDM data between the old and new schema, If you’ve created subscribers on the old schema, and now after the updates your Subscriber […]

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, […]

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EPC LTE Mobile Networks Python Software

PyHSS Update – YAML Config Files

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

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EPC LTE RFCs & Standards

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

Peculiar padding problem perplexes poor programmer.

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EPC LTE Mobile Networks Python

PyHSS Update – SCTP Support

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

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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.

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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 […]

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5G SA EPC LTE Mobile Networks

MTU in LTE & 5G Transmission Networks – Part 1

A look at MTU and its role in LTE and 5G Transmission.

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EPC Mobile Networks RFCs & Standards Software

Getting the GTP-U Packets flowing Fast – DPDK & SR-IOV

How SR-IOV and DPDK play into faster performance of Virtual Network Functions (VNFs) for 3GPP core networks.

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5G SA GSM LTE Mobile Networks RFCs & Standards Security SIM Cards

Confidentiality Algorithms in 3GPP Networks: MILENAGE, XOR & Comp128

A look at the Confidentiality Algorithms used in 3GPP Networks, MILENAGE, XOR & Comp128

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EUTRAN Mobile Networks

Enable GPS/GLONASS Sync on Huawei BTS3900

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 […]

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GSM LTE Mobile Networks Security SIM Cards

SIM / Smart Card Deep Dive – Part 3 – APDUs and Hello Card

A look at APDUs and Interacting with Cards

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GSM LTE Mobile Networks Security SIM Cards

SIM / Smart Card Deep Dive – Part 2 – Meet & Greet

The basics of Smart Cards & their File System

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GSM LTE Mobile Networks Security SIM Cards

SIM / Smart Card Deep Dive – Part 1 – Introduction to Smart Cards

Getting up close and personal with Smart Card / SIM Cards

Categories
EPC EUTRAN LTE Mobile Networks RFCs & Standards

Cell Broadcast in LTE

A look at how Cell Broadcast is signalling implemented between the MME and CBC in an LTE/EPC network.

Categories
EUTRAN LTE Mobile Networks

Huawei BTS 3900 LMPT Basic Config

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 […]