Düsseldorf, 15. September 2014 – ZTE, a publicly-listed global provider of telecommunications equipment, network solutions and mobile devices, and German network operator E-Plus have announced that they are cooperating on the deployment of an IMS (IP multimedia services) based core network infrastructure. This will be the basis for a commercial voice-over-LTE (VoLTE) service in the E-Plus network.

Since 2013, when large-scale commercial LTE networks began to be established all around the world, the question of how to launch 4G voice services has been important to all major operators. By using 4G LTE’s high-speed mobile communications technology , VoLTE provides high-quality voice services for end users through the IMS core network.

With ZTE'S help, E-Plus deployed the IMS core network within only a few months and has already started testing VoLTE services for commercial use in the E-Plus network. Compared with CSFB (circuit switched fall back) technology that makes voice calls ‘fall back’ to the 3G network, VoLTE provides higher-quality voice services for end users and improves the user experience. In addition, the eSRVCC (enhanced single RAN voice call continuity) flow for switching voice services from the 4G IMS network to the 3G CS network ensures that when a 4G LTE user migrates from a place covered by the 4G network to a coverage hole in the 4G network, the user's voice services can be smoothly switched to the 3G network. In this way, 4G LTE users can enjoy uninterrupted and stable voice services.

Christoph Bladoschewski, Department Manager Voice and Services at E-Plus said: “It has become a tradition that E-Plus, with our strategic partner ZTE, leads the market in introducing new technologies in the core network. The introduction of IMS in such a short time is a true masterpiece by ZTE.”

Li Jun, CEO of ZTE Deutschland GmbH, said: "We are very honoured to provide IMS network and VoLTE solutions for E-Plus. ZTE's VoLTE solution will help E-Plus to provide high-quality voice services and guarantee high-bandwidth data services based on LTE access. ZTE’s implementation of the VoLTE technology will also help improve E-Plus's network profitability."

Since 2009, ZTE has been providing 3G and 4G radio products, PS (packet switch) and EPC (enhanced packet core) products and iVAS (integrated value-added services) products for E-Plus. In 2013, ZTE was named as the "Best Supplier" by E-Plus. The commercial UMTS network and PS core network have been deployed with ZTE's devices in the existing E-Plus network, and the LTE network and the EPC were put into commercial use in early 2014.