A system and method are disclosed for exchanging data in a heterogeneous wireless communications environment. A mobile device initiates a first communication session with a first radio access network (RAN) that is connected to a wired network comprising a remote fixed node (RFN). A first set of data exchange transactions with the RFN is initiated by the mobile device during the first communication session to exchange a first set of data. The mobile device then initiates a second communication session with a second RAN that is likewise connected to the wired network. A second set of data exchange transactions with the RFN is initiated by the mobile device during the second communication session to exchange a second set of data contemporaneously with the first set of data exchange transactions.