User equipments (UEs) that have multiple radio access technologies (RATs) are grouped together so that each group may be subjected to its own set of medium access (MAC) protocols for each RAT, while a flow destined for a UE may be communicated via one or multiple aggregated RAT interfaces on the said UE. The network operator or service provider that serves a plurality of subscribers defines a service group for said plurality of subscribers and controls the corresponding virtualized MACs for the said service group.