Second part in our MMS series, in this one we look at Mobile Terminated MMS.
Category: RFCs & Standards
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 […]
A deep dive into Mobile Originated MMS via the MM1 Interface
A brief look at International Signaling Point Code numbering and what it all means.
Getting from Point Code A to Point Code Z.
Setting up our GNS3 environment with a bunch of SS7 Nodes
Looking at the basic components that make up our SS7 Networks.
Taking a look at the basics of the SS7 Protocol Stack.
A look at attack vectors the NRF opens up in #5G Core networks, and the mitigations recommended by 3GPP.
Looking for Love in the 5G Core?
Let’s look at our matchmaker – The Network Repository Function in 5G Core.
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 […]
A glimpse into the complexities of prepaid billing (Online Charging) Diameter based networks.
A look at how the HSS can update the profile of an already in-use subscription using Insert Subscriber Data Request/Response.
A Bind environment in a Docker container for experimenting and learning ENUM for DNS based Call Routing.
Using DNS to resolve E.164 phone numbers to routable SIP URIs
A look at Multimedia Messaging (MMS) in 3GPP Networks and how it actually works.
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 how it worked, reading references that looped into other references, in this case I was encoding MSISDN AVPs in Diameter. How to Encode a number […]
As the number of Private Networks built on LTE and 5G grow, how will PLMN allocation be managed?
Categories
SCTP Parameter Tuning
A look at tuning your SCTP parameters to detect failures quickly and reduce dropped packets when they happen.
5G introduces Network Slicing, or does it? A look at slicing mechanisms widely used in pre-5G networks.