You may think paging is overly complex. Especially so when you recall that it can be used in conjunction with segmentation. In such instance the segmentation mechanism described earlier is first used to produce a 32-bit address which is then subjected to the paging mechanism just described. Only the 386/486 has the paging ability-the 286 has segment addressing but not page addressing-and paging is responsible for much of the 386/486’s superiority. For example, by altering the entries in a page table, an address produced by segmentation can be made to refer to any physical memory location. This means that it is possible to make it seem as if any 4KByte page can move its location in memory by changing the contents of a single location is a page table. This allows a 386/486 system to reorganise its memory by mapping any 4KByte page anywhere it is needed.
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