Suitability of cryptographic modes of operation for the encryption in high-speed networks

Today, modern applications require more and more bandwidth as a result of the increasing quality and performance of the applications. Not only, the bandwidth requirements have to be met but also the demand for data confidentiality. Therefore, new or modified cryptographic modes of operation are required, which usually, provoke error propagation resulting in a higher error rate. The influence of the modes on the quality of service parameters in ATM is examined using the CBC and the ATM counter mode. The different changes of the QoS parameters are described in this paper For SDH we suggest the statistical self-synchronization, based on the OFB mode, because it does not require bandwidth and is self-synchronizing with acceptable augmentation of error rates. Guidelines for adjusting selected cryptographic parameters are presented.