Explanation:

• The interim data solution of CDMA is called IS-95B.
• IS-95B is already being deployed worldwide, and provides high speed packet and circuit switched data access on a common CDMA radio channel by dedicating multiple orthogonal user channels (Walsh functions) for specific users and specific purposes.
• The 2.5G CDMA solution, IS-95B supports medium data rate (MDR) service by allowing a dedicated user to command up to 8 different user Walsh codes simultaneously and in parallel for an instantaneous throughput of 115.2 kbps per user (8*14.4 kbps)
• However, only about 64 kbps of practical throughput is available to a single user in IS-95B due to the slotting techniques of the air interface.
• IS-95B also specifies hard hand-off procedures that allow subscriber units to record different radio channels in the network without instructions from the switch so that the subscriber units can rapidly tune to different base stations to maintain link quality.