These charges represent a major portion of the cost to acquire and operate a fare collection network. CDPD is an overlay to the existing national cellular telephone system. CDPD supports low cost digital data communications over the unused, idle portion of the existing cellular telephone spectrum. CDPD charges are based on the actual volume of data transmitted and received. All devices connecting through CDPD are continuously on line and available, but no charges are incurred unless, and until, data from a CDPD device is actually sent or received.
CDPD modems are the only equipment a transit company needs to purchase.
Low cost to operate. CDPD data communications costs are comparable to the costs for local measured telephone services. Simple and inexpensive installation. CDPD modems are small, and only require connection to an external, cellular antenna. Fare collection equipment can be moved without installing cable, conduits, or phone lines.