Implementation of Robust Solid State Drive Controller Using LZ77 Compression and SHA-1 Encryption Technique

Abstract

Solid State Drive (SSD) Technology is used to read/write data from host to the flash device with high speed and low power. Data compression technique represents data in compact form which can be achieved by data redundancy, while retaining the data content using lossless data compression. Secure hashing algorithm-1 (SHA-1) encryption algorithm encrypts data by modifying information and by inserting messages from fraudulent source, deletion and recording sequence. This paper deals with solid state drive using LZ77 compression algorithm and SHA-1 encryption algorithm for robust compression and encryption in SSD devices. The proposed method LZ77 Compression algorithm employs a text window in conjunction with a look-ahead buffer. For matched character, if pointers are selected with effective encoded offset position then it results in better compression ratio. For the unmatched character, compression ratio is 3.12 times better than the existing algorithm. To securely transfer the data in SSD device, data must be encrypted using SHA-1 encryption algorithm. Since a lossless compression is used, the process is reversible. Thus, fast and secure data transmission is possible with encryption. SSD comprises of both write and read cycle; the compressed and encrypted data is stored in flash and read at read cycle with reversible technique. In read cycle, decryption is used to retrieve the encrypted data back into its original compressed form. Here, the data is retrieved with higher speed. Hence, the performance of buffer in SSD increases. Therefore, speed of the read/write cycle can be improved upto 8 bytes/cycle.