A Practical Application

To better demonstrate how VLSM works in practical terms, Table 4-6 shows the progression from the sample network's base address (192.168.125.0) through the defined subnets. Pay particular attention to the binary and decimal translations for each subnet's base and terminal addresses. In decimal terms, you are progressing sequentially through the address space. In binary terms, you can see that each network uses a different combination of high-order bits in the last octet to identify the subnet. This might seem strange, but it is eminently logical. I distinguish between host and subnet bits in the binary address by indicating the subnet bits in bold italic and then delineating the two subfields with a dash (-). Ordinarily, ...

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