Volte Archtecture and Bearers
Volte Archtecture and Bearers
Volte Archtecture and Bearers
• What is VoLTE
• VoLTE Architecture
• VoLTE Bearer Combinations
CS: Circuit Switched
What is VoLTE?
Introduction VoLTE: Voice over LTE
• LTE networks are packet- switched. They do not include the traditional 2G/3G voice services
(CS).
• VoLTE (Voice over LTE) is the solution to provide the Voice (VoIP) and SMS service capability on
LTE networks. Requirements:
- Real time traffic
- Quality of Service
- Interoperability to existing CS voice network
• The world's first commercial VoLTE networks were launched by LGU+ and SK Telecom beginning
of August 2012 in South Korea
Overview
VoLTE Network Architecture
S6a IMS Core
HSS
Cx ISC
Sh AS
Rx Mw
EPC Core ISC
PCRF P-CSCF I/S-CSCF TAS
IMS
Mg/Mj
Gx
MME
S1- Gm H.248
MME MAP
MGCF
S11 HLR
MSS
ISUP
H.248
S5 RTP
S-GW PGW MRFP
LTE S1-U MGW
CS Core TDM
SGi PLMN/PSTN
Terminal Access Core Network Internet Application
VoLTE Architecture
Introduction
Service Architecture
Applications/Services
Plane
Common OAM,
• VoLTE architecture involves all domains Application Application Provisioning,
Servers Servers Billing, etc.
(E2E) being the core domain the most
relevant. VoIP/VoLTE requires support from
IP Multimedia Subsystem (IMS)
• IMS architecture provides integrated voice, Core Network
data and multi-media services Session
Control Plane Session Centralized
interworking between different access Control Databases
networks.
CSCF HSS
• IMS is based on SIP call control for
creating, modifying, and terminating
sessions. Access
Network
• IMS Enables integrated voice, data and
multi-media services
• Interworking between different Access
Networks
S-GW P- GW
Dedicated bearer
RTP QCI=1
S1-U 5. Voice Media Transmission
2. IMS VOIP registration (SIP signalling)