Voice over LTE (VoLTE) is a standardized set of specifications for using the LTE mobile data network to carry voice calls. Currently, LTE networks are used almost exclusively for data transfer (meaning, using the internet on mobile devices) purposes, while mobile voice calls, SMS and MMS services are handled by legacy (2G/3G) network infrastructure.
There are many advantages to using VoLTE for handling voice calls on the mobile network, such as:
- VoLTE has a much higher capacity for carrying voice calls compared to 3G (and of course 2G).
- Among other things, this larger capacity allows for substantially higher call quality compared to older technologies.
- 4G LTE’s range is substantially wider than 2G or 3G, allowing for better signal coverage.
- Using VoLTE, Mobile Network Operators (MNOs) can free up 2G/3G bandwidth, lowering operating costs and improving call quality for calls handled on legacy infrastructure.
Voice over LTE relies on a network architecture system called IMS (IP Multimedia Subsystem). IMS is used to deliver internet (IP)-based multimedia services over the mobile network. Here we provide a breakdown of the technical part of our solution, explaining what each element does.
The IMS Core
The IMS core contains several control functions: mainly the Call Session Control Function (CSCF), the Media Gateway Control Function (MGCF), and the Breakout Gateway Control Function (BGCF).
The CSCF manages signaling between UEs (User Equipment, meaning mobile devices like cellphones and tablets) and the network, for everything related to multimedia services. The MGCF controls media gateways, which convert signals between different types of network protocols, to allow the multimedia services to work together with the Public-Switched Telephone Network.
The Media Resource Function (MRF)
The Media Resource Function is a multimedia services platform. The MRF performs media manipulation and processing. It allows adding multimedia-based communication capabilities such as voice and video calls, instant messaging, media streaming, small file transfers, and more.
The Multimedia Telephony (MMTel) Telecom Application Server (TAS)
The TAS is the layer in the network that provides developers a platform for building and deploying multimedia apps and services for the IMS network. Since the AS is open, new services can be developed without dependency on a single vendor, as happens when buying a traditional SCP for the mobile network.
Interested in the Modulo VoLTE solution? Contact us here.