Abstract
Data storage provides an open field of innovation for Error control coding (ECC). Hard disk drives (HDDs)and Solid State Drives (SSDs) typically utilizes non-removable media and therefore there is no need to standardize ECC. This presentation will provide an industry perspective of the error control problem for hard disk drives (HDDs) and solid state drives (SSDs). In the first part we will focus on HDDs and review some specifics on how the data is stored and processed as it relates to ECC. We will review defects, overwrites, and sector sizes and how they impact ECC requirements. Iterative decoders with turbo equalization will be described as well as long-sector format and soft-track ECC decoding. Then we will review NAND flash based SSD storage and the challenges as it relates to ECC. The focus will be on LDPC codes, but we will also discuss BCH codes, and trellis codes modulation as well as applications of RAID.