CDMA One : 

CDMA one refers original ITU IS-95 CDMA wireless interface protocol. It is considered as a 2G mobile wireless technology
The version IS-95A protocol employs a 1.25 Mhz carrier and data speeds up to 14.4 Kbps
The version IS-95B support data speeds up to 115 kbps by employing 800 MHz / 1.9 GHz.

CDMA2000 :

Also known as IMT Multi-Carrier, a family of 3G mobile technology standards.
Used for sending voice, data and signaling between cell sites and mobile pones
The standards such as CDMA2000 1X, CDMA2000 EV-DO Rev. 0, are approved radio interfaces for ITU IMT-2000
CDMA 2000 is backward compatible with its previous 2G iteration IS-95   _{Your Comment}