 These changes were transparent to the file system implementation in the DOS kernel, since on the file system's abstraction level volumes are seen as a linear series of logically addressable sectors, also known as "absolute sectors" (addressed by their "Logical Sector Number" ("LSN"), starting with LSN 0) independent of the physical location of the volume on the physical medium and its geometry.The underlying DOS-BIOS translated these logical sectors into physical sectors according to partitioning information and the drive's physical geometry.The drawback of this approach was a less memory-efficient sector buffering and deblocking in the DOS-BIOS, thereby causing an increased memory footprint for the DOS data structures.