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Non-volatile memories suffer from two challenges due to their physical and system-level constraints. One challenge is limited memory lifetime, also called the endurance problem. The other is the difficulty in deleting data securely, called the insecure deletion problem. This paper proposes a coding scheme that addresses both challenges jointly. It studies the secure write-efficient memory (WEM) by analyzing its rewriting-rate equivocation region and secrecy rewriting capacity. It also presents an optimal code construction for a large family of secure WEM channels. [ABSTRACT FROM AUTHOR]

We propose efficient coding schemes for two communication settings: 1) asymmetric channels and 2) channels with an informed encoder. These settings are important in non-volatile memories, as well as optical and broadcast communication. The schemes are based on non-linear polar codes, and they build on and improve recent work on these settings. In asymmetric channels, we tackle the exponential storage requirement of previously known schemes that resulted from the use of large Boolean functions. We propose an improved scheme that achieves the capacity of asymmetric channels with polynomial computational complexity and storage requirement. The proposed non-linear scheme is then generalized to the setting of channel coding with an informed encoder using a multicoding technique. We consider specific instances of the scheme for flash memories that incorporate error-correction capabilities together with rewriting. Since the considered codes are non-linear, they eliminate the requirement of previously known schemes (called polar write-once-memory codes) for shared randomness between the encoder and the decoder. Finally, we mention that the multicoding scheme is also useful for broadcast communication in Marton’s region, improving upon previous schemes for this setting. [ABSTRACT FROM PUBLISHER]