Wireless: Free software enhances remote keyless entry security

Freescale Semiconductor has developed a variable key security protocol software library designed to enhance the security of remote keyless entry systems for industrial and other applications.

By Control Engineering Staff August 28, 2008

Remote keyless entry (RKE) systems make it easy to open a car or garage door, operate a wireless alarm system, or change climate control settings with the click of a button. With this added convenience comes the threat of theft and other security vulnerabilities. To address these concerns, Freescale Semiconductor developed a variable key security protocol (VKSP) software library designed to enhance the security of RKE systems used for industrial, automotive, and consumer applications. It is free of charge to developers using Freescale embedded products.The company says its VKSP software library provides an alternative, end-to-end solution for applications that currently use radio frequency (RF), RKE and passive-entry systems. Using a key fob or similar wireless device, RKE systems enable users to release trunk latches, unlock doors to cars and buildings, and remotely control any function that requires authentication prior to use or entry. Traditional RF-based RKE systems employ limited commands and are vulnerable to outside intrusion or user-related errors. Intrusions and malfunctions can trigger the system to re-sync with the receiver, resulting in unwanted delays in operation.Unlike traditional RF and RKE system approaches, Freescale’s software library is said to support one-way authentication with a 128-bit key. It also features a time-based algorithm that does not require resynchronization if the key fob button is pressed many times when out of range of the receiver. The software library provides 254 different commands and uses a layer design on the receiver and transmitter, providing user flexibility with different non-volatile memory and encryption drivers.The company says the receiver is designed as a state machine system, which eases the integration and interaction with other complex modules.The VKSP software library provides a comprehensive solution for RKE systems based on Freescale’s microcontrollers (MCUs). It also offers developers the ability to design-in the VKSP software library with their proprietary systems.The complimentary VKSP software library is available for use with Freescale’s S08 MCUs. Freescale plans to offer the software for other Freescale MCU families in the near future.To help simplify the design process with VKSP software, Freescale offers the KITVKSP-EVAL evaluation kit featuring three development boards:• DEMO9S08SH8 demonstration board (receiver main board) based on Freescale’s MC9S08SH8 8-bit MCU;• MC33696MOD434EV RF transceiver module used with the DEMO9S08SH8 board; based on Freescale’s 433MHz MC33696 UHF transceiver; and• VKSP-KEYFOB battery-powered transmitter board based on the ultra low power MC9S08QE8 MCU.Each board can be ordered separately. The KITVKSP-EVAL kit and the VKSP-KEYFOB board suggested prices are $149.99 and $34.99, respectively. The evaluation system ships with a DVD featuring a Special Edition of the CodeWarrior tool suite and the free VKSP software library. Code examples, walkthroughs and user manuals also are available to augment developers’ productivity.— C.G. Masi , senior editorControl Engineering Machine Control eNewsletter Register here and scroll down to select your choice of eNewsletters free.