Understanding auto summary

[nbhayman1]

Hi all,

Im studying the 100-105  Cisco book to trying and understand how auto summary works. Applying what is said in the last line of the last paragraph has me stumped as I can't see how replacing the 172.16.0.0 network on the left eliminates the discontigious network.

Thanks

Nick 

[Richard Burts · Accepted solution]

I agree with you that the last part of the paragraph is poorly written (or that it is just plain WRONG). Logically it should have said to use a third classful network on the left in place of network 10.0.0.0.

HTH

Rick

[nbhayman1]

Thanks Rick,
It was driving me crazy cuz I just thought I was having trouble with the concept of classfull networks! I checked the books errata but nothing was listed.
Thanks again

[Richard Burts]

I am glad that my explanation was helpful. It is unfortunate but things like this do appear from time to time in books despite the efforts of authors and proof readers. I hope they will recognize this and add it to their errata list.

HTH

Rick