scope:

This Recommendation introduces a functional model and service scenarios related to the support of QoS enabled mobile Voice over IP (VoIP) service in WiFi, 3G, and mobile WiMAX networks. More specifically, this Recommendation provides a description of:

• a functional model applicable to the context of QoS-enabled mobile VoIP service;

• service scenarios related to the provision of QoS-enabled mobile VoIP service:

- in a single operator's network which supports either WiFi,  3G or mobile WiMAX;

- in multiple operator's networks, each supporting a different wireless network, e.g. WiFi, mobile WiMAX or 3G wireless network;

- in a single operator's network where the user terminal moves between different wireless access networks.