Cellular control boxes provide an alternative to standard phone lines that are expensive to install and maintain and are becoming increasingly scarce and unreliable for data transfer via obsolete modem technology. In many instances the monthly cellular fees are less than that of a business landline.
If you are upgrading a current system, cellular control boxes may not be compatible with older telephone entry systems. Using a cellular control box with an older system may require a circuit board upgrade for the entry system.
Cellular entry systems are billed monthly.