With all this talk of 5G and now 6G, it’s sobering to think that the majority of roaming agreements today use 2G/3G and CAMEL for all the realtime charging.
So what is CAMEL and how does it work for charging mobile subscribers?
CAMEL handles charging in 2G and 3G networks, much like Diameter handles charging in LTE.
CAMEL runs on top of SS7, specifically it sits on top of TCAP, which sits on top of SCCP, which can ride on M3UA or MTP3 (so it sits at the same layer as MAP).
CAMEL is primarily focused on charging for Voice & SMS services, as data generally uses Diameter, so it’s voice and SMS we’ll focus on.
CAMEL is spoken between the MSC (gsmSSF) and the OCS (gsmSCF).
Read more: 
LinkedIn: