VXA tapes offer significant technological and practical improvements over the DLT-V, SLR, DDS, and AIT tape formats that they compete against. Each of the other formats utilize similar methods of writing long, thin, narrow tracks of parallel data to the tape surface, which carries with it a number of disadvantages. The most significant of these is the nature of the tape drive head that reads and writes to the tape.

Tracked tapes require very precise alignment between the tape surface, and the drive head, which cannot be allowed to shift between different reads and writes. To keep up with the demand for ever greater data density, it has been necessary to compress each track to an ever narrower stripe across the tape surface, which increases the risk of an introduced error. Bad alignment, worn tapes or drives, inconsistent temperature variations (such as the heat generated by the drive itself), and extreme temperatures each have an effect on the tape.

Tracked tapes do offer some degree of error checking and fault tolerance; however, in order to properly do this, it is necessary for tracked tapes to perform an operation known as "backhitching". Any time data flow is interrupted, the deck must rewind beyond the last point read or recorded, accelerate backup to the correct speed, and attempt the procedure again. While they are designed to do just that, continual operation in this manner degrades the drive and the tape surface through wear and tear. VXA tapes utilize a drum with multiple heads, like a VCR, which allows the head assembly several opportunities to read packets which may be problematic. If somehow missed by the first head, a packet may still be read without having to stop or rewind the tape. The operation of VXA tapes also allows on-the-fly error correction, whereby the head reads back data as it is written to confirm that it has been written correctly. If a discrepancy is detected, the error is fixed by a secondary head without needing to even slow down. This makes VXA tapes far more robust in terms of data integrity, with a much, much lower level of errors introduced by the hardware. Tandberg Data puts the bit-error rate at a 1 in 10 quadrillion chance.

In addition to the parity bit on each byte used for network transfer and on fault tolerant storage volumes, VXA tapes include 4-Level Reed Solomon Error Correction. This is where a matrix of packets, as they are aligned horizontally, diagonally, and vertically on the tape is formed, with additional data that is calculated by summing the bits in each of these directions to compare to what is read on each read of the tape. This extremely robust method, which essentially quadruple-checks its own integrity, allows for the loss of two packets in each row, column, and diagonal before data loss occurs. The fact that each packet has a unique address, much like a block or sector on a hard drive, allows the drive to maintain a high level of data throughput, even where such errors may result in a head missing a read on the first pass, preventing the packets from getting out of order.

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