The key to access security
01 June 2008
Nexus set up its business more than 20 years ago to market the US-based company, Datakey Electronics’ range of electronic memory keys and tokens. Providing easy, yet secure access to a variety of applications, from military communications systems to cashless snack vending machines, Datakeys are portable key-like devices that contain a non-volatile EEPROM chip and a choice of I2C, Microwire or SPI memory device interfaces. The embedded EEPROM can be written to, read and erased via these interfaces.
Electronically coded access systems such as memory cards or smart cards may be perfectly acceptable as a means of gaining access to rooms within buildings, but take these devices outside in dusty, wet, hot or cold conditions and at some stage you are likely to experience problems. Datakeys, on the other hand, are designed to cope in difficult environments for the life of the device, including the adverse effects of strong magnetic fields and electrostatic discharges.
Unlike these cards and carriers, the Datakey body protects the embedded memory chip from environmental and physical damage, while the key receptacle can be IP67 protected if the application warrants it. The type of plastic used to encase the key electronics or house the receptacle can also be varied to suit the application, providing protection against corrosive chemicals or aggressive processes such as sterilisation.
For enhanced security, Nexus can now supply Datakey Electronics’ new IIK/IIT series of unique identifier memory keys or tokens, which are equipped with a standard I2C interface. The IIK’s EEPROM has a unique 48-bit register that cannot be changed by the user, and thus cannot be copied. Nexus’ managing director, John Barrett says that customers can use the unique serial number to prevent duplication of keys by storing a list of the serial numbers before despatching the keys. This is particularly attractive to OEMs wishing to protect their IP or investments.
The application pictured here is a project Nexus carried out in conjunction with the catering microwave oven manufacturer, Merrychef. The ‘Menu Key’ system uses an LCK16000 Datakey to store up to 250 three-stage programs. Once programmed, the key is despatched to site where it is used to upload recipes and any firmware updates.
The high life-cycle receptacle developed for this key provides tactile confirmation when the key is inserted and turned. It also incorporates a special contact that can be used to protect the host bus by ensuring that the key has made secure contact with the receptacle before any signals are transmitted.
Contact Details and Archive...