The radio node controller of one subnet sends a communication to an access terminal over a control channel through the infrastructure of another subnet. The radio node controller maintains an open traffic channel with an access terminal when the access terminal moves from a coverage area of the first subnet to a coverage area of the second subnet and when the access terminal uses a carrier in the first subnet that cannot be used in the second subnet. In a radio access network including a first and a second subnet, in which the first subnet includes both a first radio node controller and radio nodes that are configured in accordance with one 1xEV-DO standard and the second subnet includes radio nodes configured in accordance with another 1xEV-DO standard, the first radio node controller maintains an open traffic channel with an access terminal when the access terminal moves from the coverage area of the first subnet to the coverage area of the second subnet.