Analog modem-to-cellular converters allow legacy equipment with built-in analog modems to connect to cellular data networks by emulating the traditional dial-up PSTN network. These devices represent a cost-effective means of updating telecommunications networks to enable landline equipment to communicate with modern wireless systems. In order to interface with legacy equipment, analog modem-to-cellular converters often include integral ports for registered jacks (RJ) and serial equipment. Additionally, they are often fitted with LED's or other status indicators.
A typical analog modem-to-cellular converter. Image credit: MultiTech / Eddy Wireless