Consider a 5-bit linear-feedback shift register (LFSR) with the following recursive rule: (n + 1)-th bit = (n − 2)-th bit ⊕(n − 4)-th bit, for n ≥ 5. i. Demonstrate one step of this LFSR, with the aid of a schematic, starting from seed 11010.
时间: 2023-12-31 22:03:20 浏览: 75
一个n-LFSR给定结构常数具有“由-序列密码(大全)
Sure! Here's a schematic of the 5-bit LFSR with the given recursive rule:
```
+--->(+)---(n-2)------+
| |
| v
11010 ---| (+)
| |
+--->(+)<---(n-4)<---+
```
Starting from the seed 11010, we first shift all bits to the right:
```
11010 -> 01101
```
Then, we compute the next bit using the recursive rule:
```
(n + 1)-th bit = (n − 2)-th bit ⊕(n − 4)-th bit
= 1 ⊕ 1
= 0
```
So the next bit of the LFSR is 0. We add this bit to the left of the shifted register:
```
01101 -> 00110
```
And that's one step of the LFSR starting from the seed 11010.
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