Docker & BIND as an ENUM Playground
Nick A Bind environment in a Docker container for experimenting and learning ENUM for DNS based Call Routing.
2021
ENUM – DNS based Call Routing
Using DNS to resolve E.164 phone numbers to routable SIP URIs
Looking inside the MMS Exchange (With call flow and PCAP)
A look at Multimedia Messaging (MMS) in 3GPP Networks and how it actually works.
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…
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?
How UEs get Time in LTE
How does "Network Time" actually get to the UE?
Diameter Agents
A look at the 4 types of Diameter Agent
SCTP Parameter Tuning
A look at tuning your SCTP parameters to detect failures quickly and reduce dropped packets when they happen.
Australia’s fake Phone Numbers
Numbers that will never connect, reserved for use in TV/Movies & Books.
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.
Pre-5G Network Slicing
5G introduces Network Slicing, or does it? A look at slicing mechanisms widely used in pre-5G networks.
Adding Vlans to VMware Workstation
Setting up VLANs in Workstation to allow ever-more complicated network setups.
Adding support for AMR Codec in FreeSWITCH
Adding support for AMR Codec in FreeSWITCH
K8s multiple objects in YAML File
Defining multiple K8 objects in the same YAML file
Diameter Droplets – The Flow-Description AVP and IPFilterRules
Getting to know IPfilterRules and the Flow-Description AVP
The Surprisingly Complicated world of MO SMS in IMS/VoLTE
Short messaging can be anything but simple...
5Gethernet? – Transporting Non-IP data in 5G
A look at non-IP transport for 5G including Ethernet.
Open5Gs Database Schema Change
New database time to support slicing and a migration path for existing users.
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…
Diff + Wireshark
Comparing packet contents with Wireshark and a diff utility