Performance of Authenticated Encryption for Payment Cards with Crypto Co-processors

Many security protocols rely on authentication of communicating entities and encryption of exchanged data. Traditionally, authentication and encryption have been separate processes, however there are combined solutions, referred to as authenticated-encryption (AE). The payment card industry is revising its protocol specifications and considering AE, however there has been uncertainty around performance and feasibility on traditional issued smart cards and when loaded as applications on security chips pre-installed within devices. It is difficult to predict performance using results from generic CPUs as typical smart card chips used in payment, have slow CPUs yet fast cryptocoprocessors. This report is based on a practical investigation, commissioned by a standards body, that compared secure platform level (MULTOS) and low-level native implementations of AE on crypto-coprocessor smart cards. The work also suggests a technology independent benchmark for a CPU with cryptocoprocessor. Keywords–Authenticated encryption; EMV; OCB; GCM; ETM; CCM; smart card; crypto-coprocessor; payment; performance; MULTOS.