Before we begin this chapter, let's just do a little review of subnetting. Do you remember what subnetting is? It is simply taking a large address space divided into smaller segments. The segment size must meet the needs or requirements of the network.
The information that you need to remember will help you not only with subnetting, but also for the following topics that we will cover in this chapter:
- Variable Subnet Masking
- Route summarization
Consider the following example:
Bit values: 128 64 32 16 8 4 2 1.
These values will always remain the same per octet and the maximum value, when the values are added together, is 255.
Here is a bit-to-decimal table:
|
Bit |
Decimal |
|
10000000 |
128 |
|
11000000 |
192 |
|
11100000 |
224 |
|
11110000 |
240 |
|
11111000 |
248 |
|
11111100 |
252 |
|
11111110 |
254 |
|
11111111 | ...