Access (UMA) standard.
depending on the access network to which the handset is
connected. When the DMH is connected to the mobile
radio network, services are delivered from the mobile core
service platforms, but when the DMH is connected via Wi-
Fi, service is delivered from a different, fixed network service
platform.
differences between the two service domains, as well as
enable the transfer of an active call between domains.
This approach to DMH services is best represented by
the 3GPP Voice Call Continuity (VCC) standardization
initiative.
as the basis for their DMH services. When one examines
becomes clear why they are going down the UMA path.
In the case of a dual-mode handset service, the primary
goal is to enable subscribers to leverage Wi-Fi access
networks to stay "always best connected" to their services.
To be successful, a DMH service must enable subscribers
to continue receiving all services (voice, messaging,
transition between access networks.
between mobile and Wi-Fi access networks. It enables
subscribers to receive all mobile services when on Wi-
Fi, whether circuit, packet or IMS-based, as well as the
handover of those services between networks. As UMA
enables handsets to access the same (evolving) mobile
core network through existing standard interfaces when