1VEC: Off-Chip Memory Integrity Protection for Both Security and Reliability

摘要

This paper proposes a unified off-chip memory integrity protection scheme, named IVEC. Today, a system needs two independent mechanisms in order to protect the memory integrity from both physical attacks and random errors. Integrity verification schemes detect malicious tampering of memory while error correcting codes (ECC) detect and correct random errors. IVEC enables both detection of malicious attacks for security and correction of random errors for reliability at the same time by extending the integrity verification techniques. Analytical and experimental studies show that IVEC can correct single-bit errors and even multi-bit errors from one DRAM chip within a cache block read without any additional ECC bits, when the integrity verification is also required for security, effectively removing the memory and bandwidth overheads (12.5%) of typical ECC schemes. Alternatively, with parity bits, IVEC can provide even stronger error correction capabilities comparable to the traditional chip-kill correct, still with less overheads. For both cases, IVEC can use standard non-ECC DIMMs.