【問題】mcse



贊助商連結


mok2000
2002-05-21, 03:28 PM
195. You have been given the network ID of 172.24.8.0/22 from your ISP.
All of the routers in your network use either RIP V2, or OSPF. Each of the
two subnets you will be creating will contain only 75 computers. You want
to use the most specific number of bits and the first two available
network ID numbers in your subnet mask. Drag and Drop question with the
following Answer (choose 2).

a. 172.24.12.0/22
b. 172.24.16.0/22
c. 172.24.24.0/22
d. 172.24.8.128/25
e. 172.24.9.0/25
f. 172.24.16.0/25

Answer:d,e
請問這條為何是d,e 謝謝!

贊助商連結


mok2000
2002-05-23, 05:25 PM
請問.....

EIGHTS
2002-05-23, 09:29 PM
因 172.24.8.0/22 他的位址範圍為
172.24.8.0~172.24.11.0
172.24.12.0 和 172.24.16.0 都超過這個範圍了

而 172.24.8.128/25 和 172.24.9.0/25
各網段都有 128 個 IP 位址,也剛好符合要求 (只有 75 台電腦)
26 bits 的遮罩只有 64 個 IP 也不夠

所以答案只有 D,E 符合了