With radio networks, transmissions are slow, frequencies are clogged, and there is no available spectrum for expansion. A decade ago, the public turned to cellular for the mobility of voice. Police transmissions can also take advantage of the public airwaves that cell carriers use. When wireless modems are used over cellular air waves, these modems operate on analog technology that uses RC-4 level of encryption. This prevents information from being pulled down; it cannot be cloned. Although cell phones have a circuit connect, CDPD breaks the information down to small bits of data or packets. Because the transmission is packet-based, it cannot be compromised. One of the disadvantages of CDPD is the lack of nationwide coverage; it is still a regional service; however, most law enforcement transmissions are regional. CDPD does not require the high capital, installation, and maintenance costs of a private radio network. If an agency uses any CDPD modem, uses Internet Protocol technology, or "open" technology, it also can use any vendor's laptop or software program. A cellular carrier can be hired to build and maintain the network, which provides more flexibility and less expense than under the private radio network. This article describes some CDPD case scenarios for law enforcement, as well as some CDPD technologies.