Categories
FreeSWITCH IMS / VoLTE Mobile Networks VoIP

FreeSWITCH – Incompatible Destination

A quick look at a possible cause for “INCOMPATIBLE DESTINATION” errors in FreeSWITCH.

Categories
IMS / VoLTE Kamailio Mobile Networks VoIP

Kamailio, IMS & DNS Headches

A quick post on a lesson that took me a while to learn with DNS, Kamailio and IMS.

Categories
FreeSWITCH IMS / VoLTE Kamailio Mobile Networks VoIP

FreeSWITCH, Kamailio & IMS Extensions

Bad Extension is nothing to do with the Dialplan…

Categories
CGrateS EPC IMS / VoLTE Mobile Networks Software VoIP

CGrates in Baby Steps – Part 1

Getting started with CGrateS to bill for calls in a Telecom environment.

Categories
Mobile Networks RFCs & Standards

MMS Deep Dive – MM1 – Mobile Originated MMS

A deep dive into Mobile Originated MMS via the MM1 Interface

Categories
GSM Mobile Networks SDM Software

USSD Gateway with Osmocom

Unstructured Supplementary Service Data or “USSD” is the stack used in Cellular Networks to offer interactive text based menus and systems to Subscribers. If you remember topping up your mobile phone credit via a text menu on your flip phone, there’s a good chance that was USSD*. For a period, USSD Services provided Sporting Scores, […]

Categories
Mobile Networks VoIP

Demystifying SS7 & Sigtran – Part 5 – What layer to Split

A look at taking SS7 traffic and putting it onto IP / SIGTRAN links on the MTP2 / Layer 2 level.

Categories
EPC LTE Mobile Networks

Evolved Packet Core – Analysis Challenge

This post is one of a series of packet capture analysis challenges designed to test your ability to understand what is going on in a network from packet captures.Download the Packet Capture and see how many of the questions you can answer from the attached packet capture. The answers are at the bottom of this […]

Categories
5G SA IMS / VoLTE Kamailio LTE Mobile Networks VoIP

The Surprisingly Complicated World of SMS: Apple iPhone MT SMS

Quirks and gotchas of working with SMS on IMS on iPhones.

Categories
FreeSWITCH IMS / VoLTE Kamailio Mobile Networks VoIP

FreeSWITCH as an IMS Application Server

Using FreeSWITCH as an IMS Application Server

Categories
Mobile Networks RFCs & Standards

ITU International Point Code Structure

A brief look at International Signaling Point Code numbering and what it all means.

Categories
GSM Mobile Networks RFCs & Standards Software VoIP

Demystifying SS7 & Sigtran – Part 4 – Routing with Point Codes

Getting from Point Code A to Point Code Z.

Categories
Mobile Networks RFCs & Standards VoIP

Demystifying SS7 & Sigtran – Part 3 – SS7 Lab in GNS3

Setting up our GNS3 environment with a bunch of SS7 Nodes

Categories
Mobile Networks RFCs & Standards VoIP

Demystifying SS7 & Sigtran (With Labs!) – Part 2 – Ingredients Needed

Looking at the basic components that make up our SS7 Networks.

Categories
Mobile Networks RFCs & Standards VoIP

Demystifying SS7 & Sigtran Networks (With Labs!) – Part 1 – Intro

Taking a look at the basics of the SS7 Protocol Stack.

Categories
EUTRAN LTE Mobile Networks RF

Huawei Baseband Cheat Sheet

Quick reference guide for the types and capacities of Huawei BBU 3900 Series cards

Categories
EPC EUTRAN IMS / VoLTE LTE Mobile Networks

Lifecycle of a Dedicated Bearer – From Flow-Description AVP to Traffic Flow Templates

A look at how Dedicated Bearers get established for VoLTE.

Categories
5G SA Mobile Networks RFCs & Standards SDM Security

Some thoughts on NRF Security in 5G Core

A look at attack vectors the NRF opens up in #5G Core networks, and the mitigations recommended by 3GPP.

Categories
5G SA Mobile Networks RFCs & Standards SDM

If you like Pina Coladas, and service the control plane – Intro to NRF in 5GC

Looking for Love in the 5G Core?

Let’s look at our matchmaker – The Network Repository Function in 5G Core.

Categories
GSM IMS / VoLTE Mobile Networks

The Surprisingly Complicated World of SMS: Special Characters

A look at how characters are encoded in an SMS.