VoLTE vs VoNR
VoLTE (Voice over LTE) and VoNR (Voice over New Radio) are both IMS-anchored voice services. VoLTE runs on LTE's EPS bearer; VoNR runs on 5G's QoS Flow. The IMS core — P-CSCF, S-CSCF, I-CSCF, HSS — is largely the same.
| Attribute | VoLTE | VoNR |
|---|---|---|
| Radio | LTE (E-UTRA) | 5G NR |
| Bearer | Dedicated EPS bearer, QCI 1 | 5QI-1 QoS Flow |
| Signaling | SIP + Diameter Cx/Sh | SIP + Diameter Cx/Sh (unchanged) |
| Authentication | IMS-AKA | IMS-AKA |
| Media | SRTP | SRTP |
| Attack surface change | — | Same IMS attack surface, new radio |
Verdict
VoNR is not a new voice architecture. Every SIP, IMS-AKA, and Diameter Cx/Sh weakness in VoLTE is inherited. Migration plans should reuse VoLTE audits and add radio-side testing rather than assume "5G voice" is a fresh security domain.