Is SRVCC possible for 5G VoNR to 3G in case of poor coverage?
Anyone working on VoNR?
Does we have separate IMS for 5G or shared with 4G IMS?
No, SRVCC and CSFB are not supported in 5G NR and is incompatible with legacy systems.
I’m seeing Rel16 mentioning SRVCC from 5G to 3G…
PSHO from 5G to 4G, no SRVCC to 4G.
Is this correct?
Yes you’re right,but the meaning is different.
In rel. 16, SRVCC will be supported implicitly by PSHO from NG-RAN to E-UTRAN.
The meaning is different because SRVCC from E-UTRAN to UTRAN was already supported in 4G LTE.
Hope it is clear now.
For data call transfer term PSHO used.
For voice call SRVCC.
It’s mentioned SRVCC from 5G to 3G.
PSHO from 5G to 4G.
N26 interface used for PSHO.
I think SRVCC from 5G to 3G mean to say is , 1st voice call HO between 5g to 4G and then SRVCC to 3G .Here Voice call HO possible between 5G(VONR) to LTE(VOLTE) using N26 interface between AMF and MME ( without N26 interface Voice call HO not possible between 5G to 4G N/W due to Voice interruption time) . For Voice call HO to complete ,max Voice Interruption time needed is ~300 m sec and using N26 interface it takes ~70 m sec (interruption time) . but without N26 interface Voice interruption time takes 700 m sec >300m sec(Max voice interruption time).