Wi-Fi Calling
Often associated with VoLTE (Voice over Long Term Evolution), Wi-Fi Calling is the means by which service providers can support seamless mobility between the LTE and Wi-Fi networks, whilst maintaining voice services. The course builds on the LTE System Engineering and Wi-Fi System Engineering courses and explains in detail the enhancements that need to be made to the network to support VoWi-Fi, before describing how a call is established across Wi-Fi using the services of the EPC (Evolved Packet Core) and IMS (IP Multimedia Subsystem).
Section 1 - Wi-Fi Calling Architecture
Topic areas covered include:
- Wi-Fi Calling Architecture Fundamentals:
- VoLTE and VoWi-Fi.
- Deployment Scenarios.
- Network Architectures:
- Trusted Non-3GPP Access.
- Untrusted Non-3GPP Access.
- Mobility Mechanisms:
- Host Based Mobility.
- Network Based Mobility:
- PMIPv6.
- GTP.
- Multi Access PDN Connectivity.
- Non seamless Wi-Fi Offload.
- Network Architecture:
- Untrusted Non-3GPP Access (GTP):
- UE, Access Point, ePDG, PDN-GW, AAA Server, PCRF, ANDSF.
- Protocol Stacks and Reference Points.
- IP Multimedia Subsystem:
- P-CSCF, S-CSCF, I-CSCF.
- IMS Protocols.
- Roaming Architectures:
- Home Routed.
- Local Breakout.
Section 2 - Initial Procedures
Topic areas covered include:
- Initial Procedures Fundamentals:
- Bearer Models and Bearer Mapping.
- Network Discovery and Selection:
- Network Discovery:
- RAN Assistance Information.
- ANDSF Rules.
- Accessing the Wi-Fi Network:
- Finding a Wi-Fi Network.
- Joining a Wi-Fi Network.
- WPA and Robust Security Networking.
- ePDG Selection.
- Initial Attach:
- IKEv2 and IPSec.
- EAP-AKA:
- Detailed Signalling Evaluation.
- Session Creation and Management:
- Detailed Signalling Evaluation.
Section 3 - Making and Receiving Calls over Wi-Fi
Topic areas covered include:
- Making and Receiving Calls Fundamentals.
- IMS Registration:
- IMS Identities:
- Private User Identities.
- Public User Identities.
- Service Profiles.
- Initial Registration Phase:
- Detailed Signalling Evaluation.
- Registration security Phase:
- Detailed Signalling Evaluation.
- Final Registration Phase:
- Detailed Signalling Evaluation.
- Mobile Originated Call Setup:
- VoWi-Fi to VoWi-Fi / VoLTE:
- Detailed Signalling Evaluation.
- VoWi-Fi to PSTN:
- Detailed Signalling Evaluation.
- Mobile Terminated Call Setup:
- VoWi-Fi / VoLTE to VoWi-Fi:
- Detailed Signalling Evaluation.
- PSTN to VoWi-Fi
- Detailed Signalling Evaluation.
- Emergency Calls.
- Instant Messaging.
Section 4 - Mobility and Interworking
Topic areas covered include:
- Mobility and Interworking Fundamentals.
- Wi-Fi Mobility:
- Access Point Channel Reports.
- Wi-Fi Reassociation.
- 802.11 Amendments:
- 802.11k, 802.11r.
- Wi-Fi to LTE Handover:
- Detailed Signalling Evaluation.
- Mobility when LTE Attached.
- LTE to Wi-Fi Handover:
- Detailed Signalling Evaluation.
- Wi-Fi Calling and Roaming:
- Home ePDG.
- Home PDN-GW.
- Visited PDN-GW.