Summarizing without over-summarization

r_durant

I'm sure some will say this is a CCNA question... Bear with me, just seeking clarification...

But, i'm going over the CCNP BSCI Official Exam Cert Guide 4th Ed. In ch2 Q&A, it asks...

Summarize the following without over-summarizing:
- 192.168.160.0/24
- 192.168.162.0/23
- 192.168.161.0/24
- 192.168.164.0/22

It gives the ans in the appendix as 192.168.160.0/21. While this summarizes all the addresses, I'm sure it over-summarizes with 165.0, 166.0 & 167.0 included in the summary address.

aquilla

That's correct.

192.168.160.0/24 = 192.168.160.0 - 192.168.160.255
192.168.161.0/24 = 192.168.161.0 - 192.168.161.255
192.168.162.0/23 = 192.168.162.0 - 192.168.163.255
192.168.164.0/22 = 192.168.164.0 - 192.168.167.255

Therefore the summary address of 192.168.160.0/21 is right.

S.

mkomon

Hi,

165.0, 166.0 & 167.0 are all covered by the 192.168.164.0/22 subnet. 192.168.160.0/21 makes no over-summarization.

HTH,

Martin

r_durant

aquilla wrote: »

That's correct.

192.168.160.0/24 = 192.168.160.0 - 192.168.160.255
192.168.161.0/24 = 192.168.161.0 - 192.168.161.255
192.168.162.0/23 = 192.168.162.0 - 192.168.163.255
192.168.164.0/22 = 192.168.164.0 - 192.168.167.255

Therefore the summary address of 192.168.160.0/21 is right.

S.

I feel like a dope ...I didn't expand "192.168.164.0/22 = 192.168.164.0 - 192.168.167.255"

Thanks...