Cloud-native IMS solution provides dynamic, scalable core voice, messaging and multimedia
The IP Multimedia System (IMS) is the foundation of modern voice and messaging in 4G LTE and 5G, and it lies at the very heart of most Communication Service Providers’ (CSPs) core networks. A 3GPP standard, the IMS is a framework of dozens of individual functions operating from separate application, control, and transport layer interfaces.
The IMS is designed for scalability, flexibility, and versatility. It can make the transition to cloud-native core services as well. But the IMS comprises many individual network functions. Managing their lifecycles introduces operational complexity at a time when CSPs are focused on reducing, not increasing, operating expenses.
Nokia’s solution for this problem is the new Cloud Native Communication Suite (CNCS). The CNCS is a pre-integrated IMS core, managed on the core network as a single Cloud Native Function (CNF), working predictably, reliably, and with cloud-native scale and flexibility.
“The biggest IMS application operators have today is still voice. And our customers would really like to simplify the operability of the voice core,” explains Jouni Parviainen, Nokia’s Voice over 5G Solution Manager. “Instead of having to be experts in many network elements, why not operate just one?”
In the CNCS, IMS core functions are consolidated into one single network element. This provides CSPs with a unified lifecycle management solution from start to finish. The CNCS contains all previously separate IMS network functions, including Session Border Controller (SBC), Call Session Control Function (CSCF), Telephony Application Server (TAS) and Media Resource function (MRF).
Those separate network functions are implemented as microservices within a single CNF. Nokia Container Services (NCS) can provide Container as a Service (CaaS) functionality for on-premises deployments of CNCS on bare metal servers. Kubernetes is atthe core of the NCS platform. CNCS provides a future pathway for CSPs to work with public cloud environments.
The CNCS was developed using Nokia’s own best-of-breed voice core products, said Parviainen.
“In Nokia we have all these network elements as products themselves. Now what we’ve done is inherited the functionality of those products into the CNCS,” he said.
Parviainen explained that microservice elements were extracted from those parent products, integrating them together into the CNCS. Functionalities common to individual network elements, such as database elements, have been combined and streamlined in the CNCS for maximum efficiency and scalability.
“We have optimized the interface so there is a direct connection between microservices, and we implement common functions just once,” said Parviainen.
This simplified IMS operability enables streamlined voice core network function management throughout the entire lifecycle process. External interfaces are consolidated, and internal functions are pre-integrated. The CNCS implements common Diameter dispatcher for all external diameter communication, for example. Similar IMS Core elements can be configured once together, instead of requiring separate maintenance and monitoring of each element, as standalone products require.
The CNCS also inherits its standards-based business logic from its parent IMS Core products. CSPs are presented with a single element manager with a unique operational, administration and management (OAM) interface.
The CNCS employs Zero Touch Services (ZTS) for common operational and service functions, observed on network as a single element. Inside, CNCS 3GPP standard interfaces are implemented by using direct Session Initiation Protocol (SIP) communication between business logic functions (microservices). This way SIP traffic inside the CNCS is optimized between A-SBC, CSCF and TAS functions.
Similarly, a common state database is used to decouple relevant session information
from the services logic used. Internal interfaces are abstracted away, leaving standard open interfaces external.
This exposes better debugging and monitoring capabilities than a conventional IMS core, with a single interface used for debugging. Compared to a typical IMS deployment, CNCS can streamline the process of upgrading voice core network elements from days to hours, said Parviainen.
The result: CNCS can help CSPs streamline operational costs by reducing complexity. As the entire telecom industry looks for ways to improve energy efficiency and sustainability, CNCS provides a benefit: It offers similar functionality to a conventional IMS, but with 10-20 percent lower hardware energy consumption.
Telecom is experiencing the same digital transformation effort as so many other global industries. As CSPs move increasingly to cloud-native operations they also must contend with sunsetting 2G and 3G networks. At the same time, CSPs are under enormous pressure to improve lower operational costs and improve capital expenses.
The CNCS provides a path which offers operators improved efficiency and standards-based management using the power of open Application Programming Interfaces (APIs). As a cloud-native function, the CNCS provides also CSPs with more flexibility than ever before, whether it’s to extend existing voice services, replace, or launch new special-use services on existing 4G and 5G networks.
The CNCS delivers core voice, messaging and multimedia, implemented together to act as a single product optimized for 4G, 5G, fixed and Wi-Fi deployments. This can helps CSPs achieve lower operational costs with streamlined lifecycle management: shorter installation and upgrade times, improved visibility and monitoring, and faster deployment and configuration.
