A look at how the SQN resync procedure is performed in the IMS Authentication flows
Adventures in setting up a non-working USSD Gateway for IMS
How much overhead is used to send the message “K” back to an SMS?
Using FreeDiameter, Python and our newly released “rt_pyform” module to rewrite AVPs in your FreeDiameter based Diameter Routing Agent.
A look at why we’d want to apply translations to Diameter AVPs inside a Diameter Routing Agent
Looking at overriding the default Diameter routing logic in FreeDiameter with rt_default
Diving back into the world of Diameter Routing Agents with a look at the logic that defines how a DRA routes traffic from one place to another.
Recently I had a strange issue I thought I’d share. Using Kamailio as an Interrogating-CSCF, Kamailio was getting the S-CSCF details from the User-Authorization-Answer’s “Server-Name” (602) AVP. The value was set to: sip:scscf.mnc001.mcc001.3gppnetwork.org:5060 But the I-CSCF was only looking up A-Records for scscf.mnc001.mcc001.3gppnetwork.org, not using DNS-SRV. The problem? The Server-Name I had configured as a […]
If you’ve ever received an SMS from your operator, and the sender was the Operator name for example, you may be left wondering how it’s done. In IMS you’d think this could be quite simple – You’d set the From header to be the name rather than the MSISDN, but for most SMSoIP deployments, the […]
A quick look at a possible cause for “INCOMPATIBLE DESTINATION” errors in FreeSWITCH.
A quick post on a lesson that took me a while to learn with DNS, Kamailio and IMS.
Bad Extension is nothing to do with the Dialplan…
Quirks and gotchas of working with SMS on IMS on iPhones.
A look at how Dedicated Bearers get established for VoLTE.
A glimpse into the complexities of prepaid billing (Online Charging) Diameter based networks.
Using mod_httpapi to HTTP POST call recordings to a remote server
A Bind environment in a Docker container for experimenting and learning ENUM for DNS based Call Routing.
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.
Adding support for AMR Codec in FreeSWITCH
Short messaging can be anything but simple…