Recommendations for 5G voice solutions and migration
While previous blog posts (see below) have introduced the basics about architecture and different 5G voice solutions, in this blog post we provide additional recommendations for 5G voice solutions and migration, put an eye on evolution, and provide insights on industry actions.
The recommendations for voice solutions in 5G depend on the available frequency band(s) and coverage build-out, which may differ between operators, but there are some fundamentals. Hence, the recommendation whether to use voice in EN-DC, EPS Fallback, or voice over NR depends on whether and when the NR spectrum is available in high bands, mid-bands, or low bands and whether coverage is rather spotty, local-area, or even wide-area.
Future evolution: roaming
Roaming between 4G networks is already in place today; hence, a 4G device can use E-UTRAN and EPC when roaming abroad, and this type of roaming is evolving to also support deployments of EN-DC.
This type of 4G roaming will also be used when the first 5GC networks are deployed. When more and more 5GC networks are deployed, roaming between these 5GC networks will also be introduced. The signaling between 5GC networks is at least integrity-protected or even encrypted.
Industry status and actions
GSMA has defined the VoLTE UNI (GSMA public reference document IR.92) and VoLTE roaming guidelines (GSMA public reference document IR.88). Voice in EN-DC has been profiled as an addition to these existing guidelines.
Work has been started in the GSMA to provide a UNI profile for Voice over NR in NG.114 (Ericsson took the editorship of this new public reference document) and the new 5GS roaming guidelines in NG.113. Both new public reference documents are expected to be published by the end of 2019.
Do you want to know how to take steps towards 5G voice in your network? Learn more about the network architecture for 5G voice and our recommendations for how to evolve your network.
Read more about 5G voice.
5G voice blog series
5G voice for smartphones: Network prerequisites
Voice in 5G system—architecture and EPS fallback
Migration from EPS Fallback to support voice in 5G
