Many people in our industry confuse a Diameter Signaling Controller (DSC) with a Diameter Routing Agent (DRA). While a DRA was the first and most publicized function of a DSC, and an important one at this, it is not the only function. Here are the main use cases of a DSC.
Use case 1: DRA. As discussed, this is still a critical element of a DSC and important to prevent signaling storms via load balancing the signaling load.
Use case 2: Roaming to other networks. I’ve written about this multiple times, most recently in June. With 3G networks continuing to grow, even as LTE grows, the interconnection with 3G networks and the ability to roam to/from these networks will be critical.
Use case 3: Embracing Wi-Fi and thus interworking with RADIUS. Wi-Fi is becoming a very important offload strategy for carriers, certainly for data and increasingly for voice. Seamless interworking is critical.
Use case 4: Authentication, policy, and charging seamlessly between VoLTE, VoWiFi, and 3G networks.
Use case 5: M2M is building as we all know, with an expected 2.6 billion mobile connected devices by 2019. All of these connected devices, whether they are mobile or fixed (such as gas meters) won’t be on LTE networks. They’ll be using 2G, 2.5G, 3G, and 4G to connect and enable the Internet of Things. Having a signaling controller that can manage all the different signaling interactions and convert to a coherent frame of reference for the virtual network will be critical.
Use case 6: Unlocking vendor lock-in. There are many first generation DRAs installed that don’t perform interworking with 3G networks well, or for that matter, don’t perform interworking with other Diameter instantiations or talk to other DRAs well. In fact, they don’t deal with use cases 2-5 very well at all! Second generation DSCs include these functions as part of the DSC. So if you have a first generation DRA installed, you’ll need to cost effectively include these other DSC functions and installing a cost-effective DSC next to the installed DRA can help you enable other services and revenue.