Modes of Operation
Overview
A mode of operation is a cryptographic procedure for encrypting messages of variable length. Most modes use a symmetric-key block cipher to encrypt data in a block-wise fashion. The National Institute of Standards and Technology (NIST) recommends several modes of operation, including CBC, CFB, CTR, OFB, and XTS-AES. These modes are used as industry standards for protecting financial transactions, wireless communications, and data storage.
For more information on the modes of operation approved by NIST please visit the NIST Computer Security Resource Center.
Mode Selection
Mercora Technologies offers several different variants of the NIST recommended modes of operation. Each of our modes uses the Advanced Encryption Standard (AES) block cipher for maximum security and supports 128, 192, and 256-bit key lengths. Our Standard cores come with a 32-bit IO interface and offer a compact low power design with moderate throughput. Our Fast cores offer the ultimate in performance and come with a 128-bit IO interface and are designed for applications that need high throughput and low latency.
Cipher Block Chaining (CBC)The CBC mode of operation is one of the most widely used modes in the industry. It is used in TLS/SSL, IPSec, Open SSL, WLAN 802.11, IEEE P1619, among others. Because of it's universal use it makes it ideal for applications that need to implement several cryptographic protocols on a single chip.
Cipher Feedback (CFB)CFB modes offers a compact and high throughput mode of operation. It used in Open SSL and is one of the smallest and fastest performing cores.
Counter (CTR)CTR mode is another widely used industry standard and can be seen in implementations of Open SSL, WLAN 802.11, and IEEE P1619. CTR mode is also one of the few parallelizable modes making it ideal for applications that need ultra high throughput.
Output Feedback (OFB)OFB mode provides another very compact and high throughput mode of operation. Because of its symmetry and the fact that it requires only block cipher encryption it makes it one of the smallest cores available.
Ordering Information
The CBC, CFB, CTR, and OFB IP Cores are available for licensing through Mercora Technologies. All of our cores are customizable to meet a customers needs and specifications. Please contact a sales associate This email address is being protected from spambots. You need JavaScript enabled to view it. for more information.