IEEE 802.21

[citation needed] Crossing different administrative connectivity domains will require agreements among different network operators.

In smartphones today, a user can manually select to use WiFi or cellular LTE, but the connections are not automatically maintained should a disconnection of one network occurs.

Unlicensed Mobile Access (UMA)[citation needed] technology is a mobile-centric version of 802.21.

Since June 19, 2005, UMA is a part of the ETSI 3GPP standardization process under the GAN (Generic Access Network) Group.

The Evolved Packet Core (EPC) architecture for Next Generation Mobile Networks (3GPP Rel.8 and newer) provides the Access Network Discovery and Selection Function element (ANDSF)[citation needed] (see 3GPP TS 23.402 and 3GPP TS 24.312).