Double Check access-list

From: Leigh Harrison (ccileigh@gmail.com)
Date: Thu Oct 06 2005 - 10:48:30 GMT-3


Hey there,

Could someone double check this for me? I think I've been staring at
the screen too long....

 From IEWB lab vol 1 17 Q.10

Use the minumum lines necessary to deny these hosts:-

200.0.1.2
200.0.3.2
200.0.3.10
200.0.1.18
200.0.3.26
200.0.1.10
200.0.3.18
200.0.1.26

I worked it out like this:-

128 64 32 16 8 4 2 1 #
 0 0 0 0 0 0 0 1 1
 0 0 0 0 0 0 1 1 3

 0 0 0 0 0 0 1 0 2
 0 0 0 0 1 0 1 0 10
 0 0 0 1 0 0 1 0 18
 0 0 0 1 1 0 1 0 26

 From that, in the third octet, the only bit that cnages is 2 and both
variables are present. In the fourth octet, the only bits that change
are the 16 and 8 bits and all 4 variables are present.

So I came up with :-
access-list 1 deny 200.0.1.2 0.0.2.24
access-list 1 permit any

However, the official answer is:-
access-list 1 deny 200.0.1.2 0.0.2.8
access-list 1 deny 200.0.1.18 0.0.2.0
access-list 1 deny 200.0.1.26 0.0.2.0
access-list 1 permit any

Am I missing something ?!?

Time for a brew.....
LH



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