The remote monitoring of equipment is facilitated through the use of GSM cellular communication systems. Various implementation methods are possible, ranging from integrated GSM solutions through to external GSM Modems that are capable of operating over the standard 900 MHz frequency. Dual band modules can also operate at 1800 and 2100 MHz. These modems support SMS messaging and voice communication and can be programmed raise an alarm, operate as an event monitor and interface with computer networks. They require a SIM card that is separately supplied. All GSM modules need an aerial and the range includes external fixed and magnetic mount aerials as well as internal aerials that can be incorporated into the monitored equipment. Consideration should be given to the location of the monitored equipment with respect to cellular towers, as well as the fact that it may be necessary to select a high gain antenna. Integrated GSM solutions require a GSM module and an interface board which may be built into the equipment to be monitored. Various GSM accessories are available, including power supplies, adaptor cables, backup batteries and configuration tools to facilitate a complete installation. Manufacturers of GSM equipment include CEP, Smarteq, Jiashan Jinchang and Telit.