Recent Posts

Wireguard in Mikrotik RouterOS

19/09/20211 min read
Quick intro to setting up Wireguard interfaces in Mirktok’s RouterOS.
Originating calls in FreeSWITCH

Originating calls in FreeSWITCH

12/09/20213 min read
Through fs_cli you can orignate calls from FreeSWITCH. At the CLI you can use the originate command to start a call, this can be used for everything from scheduled wake up calls, outbound call centers, to war dialing. For example, what I’m using: originate sofia/external/[email protected]:5061 61399999995 XML default originate is the command on the FS_CLI […]
Some thoughts on NRF Security in 5G Core

Some thoughts on NRF Security in 5G Core

29/08/20214 min read
A look at attack vectors the NRF opens up in #5G Core networks, and the mitigations recommended by 3GPP.
If you like Pina Coladas, and service the control plane – Intro to NRF in 5GC

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

28/08/20213 min read
Looking for Love in the 5G Core? Are you a lonely UDM from MCC 001 MNC 001, just looking for a connection? PLMN 901/70, NRF, seeks same. Let’s look at our matchmaker – The Network Repository Function in 5G Core.
The Surprisingly Complicated World of SMS: Special Characters

The Surprisingly Complicated World of SMS: Special Characters

22/08/20214 min read
A look at how characters are encoded in an SMS.
Forsk Atoll – Importing Antennas

Forsk Atoll – Importing Antennas

21/08/20211 min read
Importing .msi antennas radiation patterns into Atoll
Backing up and Restoring Open5GS

Backing up and Restoring Open5GS

15/08/20213 min read
How to backup and restore Open5Gs config between servers
GTP Extension Headers (PDU session user plane protocol) in 5GC

GTP Extension Headers (PDU session user plane protocol) in 5GC

14/08/20212 min read
How GTP is extended in 5G Core Networks to support extra QoS functionality like Reflective QoS and Delay Indicators
The Surprisingly Complicated World of SMS: Concatenated / Multipart SMS

The Surprisingly Complicated World of SMS: Concatenated / Multipart SMS

08/08/20214 min read
Another deep dive into deceptively simple seeming functions to do with SMS.
Framed Routing in 5G

Framed Routing in 5G

07/08/20212 min read
5GC includes native support for framed-routing.
Reflective QoS in 5G

Reflective QoS in 5G

01/08/20212 min read
A great new feature of #5G Core Networks is Reflective QoS – Where QoS of the traffic coming to a UE is reflected on the QoS coming out.
When moving the telephone exchange is easier than moving the lines within it…

When moving the telephone exchange is easier than moving the lines within it…

31/07/20211 min read
Relocating vast numbers of subscriber lines is something to be avoided. In 1929 Indiana Bell realized they needed a larger telephone exchange (“CO” to use the US term) to meet growing demand, and while there was vacant land around the current building, it wasn’t large enough to build on with the current building slap-dab in […]
Kamailio Bytes – Using Rtimer to run Jobs

Kamailio Bytes – Using Rtimer to run Jobs

25/07/20212 min read
Using the Rtimer module and UAC to be annoying, or very useful.
SMS in 5GC

SMS in 5GC

24/07/20213 min read
The first SMS was sent in 1993, and all these years later as 5G rolls out, we’re still supporting it.
5G Online Charging with the Nchf_ConvergedCharging SBI

5G Online Charging with the Nchf_ConvergedCharging SBI

18/07/20216 min read
There’s no such thing as a free lunch, and 5G is the same – services running through a 5G Standalone core need to be billed. In 5G Core Networks, the SMF (Session Management Function) reaches out to the CHF (Charging Function) to perform online charging, via the Nchf_ConvergedCharging Service Based Interface (aka reference point). Like […]