Cable Authentication

There are many reasons to manage the connectivity between a system and various plug-in components. Traditionally this control has been accomplished by using mechanically unique connectors and plugs. While this physical technique can prevent mistakes, i.e., plugging the wrong cable into the wrong socket; it is much less effective at preventing the interconnection of products of unknown origin into an equipment type.

Electronic authentication techniques are available today that allow peripherals, probes, and even cables to be authenticated prior to being enabled for operation by the system. A manufacturer can decide to build the authentication function into a cable or into an end-point of the cable, for example a probe, sensor, or actuator, depending on economics or convenience.

Cable Authentication ICs in Cable Connector

Cable Authentication ICs in End-Point

In some cases it makes sense to authenticate the cable at the connector, for example when adding dedicated wires for the authentication function is prohibitive. In other cases performing authentication at the end-point makes more sense. If a manufacturer has many different end-point part numbers, performing authentication in the cable can result in a standard authenticated cable that can be used with the different end points, and the end-point designers don't have to worry about authentication.

Authentication Alternatives

There are many forms of electronic authentication available. Simple methods such as an unchanging bit stream challenge that looks for a simple bit stream response can be easy to implement, but the authentication can also be defeated fairly easily. Using a more secure authentication technique will make much more difficult or economically impossible to defeat.

Maxim Solution

Maxim DeepCover® Secure Authenticators were designed for applications that have the most stringent of security needs; those where reputation protection, property protection, or profit protection are of the highest concern.

Maxim's Deep Cover secure authenticators provide strong, but affordable, cryptographic security using standards-based algorithms and provide all of the functionality to make design simple.

Cable Authentication Block Diagram using Secure Algorithm

Cable Authentication Block Diagram using Secure Algorithm

In the above diagram, only one cable pin is needed to implement strong authentication within a cable. The single signal line carries both power and data.

Resources

DS28E15
DeepCover Secure Authenticator with 1-Wire SHA-256 and 512-Bit User EEPROM

  • Symmetric-Key-Based Bidirectional Secure Authentication Model Based on SHA-256
  • Strong Authentication with a High-Bit-Count User-Programmable Secret and Input Challenge
  • 512 Bits of User EEPROM Partitioned Into Two Pages of 256 Bits