# Access List (please explain this this...)

Please match Access LIsts to IP Addresses (not all access list used)

Access lists

1. access-list 2 deny 172.26.48.0 0.0.15.255

2. access-list 3 deny 172.26.64.0 0.0.31.255

3. access-list 4 deny 172.26.128.0 0.0.31.255

4. access-list 5 deny 172.26.192.0 0.0.31.254

5. access-list 6 deny 172.26.192.1 0.0.31.254

A. 172.26.92.10

B. 172.26.198.94

C. 172.26.50.173

D. 172.26.144.17

3A

5B

2C

4D

I could not figure out this calculation, can you explain me please how to get those answers!!!

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## Replies

Jay_Jones Mon, 10/29/2007 - 02:13

I am a bit confused by list 4 & 5 but I think these are the correct range and answers

1. access-list 2 deny 172.26.48.0 0.0.15.255 range = 172.26.48.0 - 172.26.63.255

2. access-list 3 deny 172.26.64.0 0.0.31.255 range = 172.26.64.0 - 172.26.95.255

3. access-list 4 deny 172.26.128.0 0.0.31.255 range = 172.26.128.0 - 172.26.159.255

4. access-list 5 deny 172.26.192.0 0.0.31.254 range = 172.26.192.0 - 172.26.223.254

5. access-list 6 deny 172.26.192.1 0.0.31.254 range = 172.26.192.1 - 172.16.224.255

A. 172.26.92.10 = 2

B. 172.26.198.94 = 5 or 4

C. 172.26.50.173 = 1

D. 172.26.144.17 = 3

As I see it you are being asked what IP addy fits in the range of the access list

bvsnarayana03 Mon, 10/29/2007 - 02:32

Option 4 is a network address, while 5 is an IP add. So, B belongs to option 4.

cmccullough5 Mon, 10/29/2007 - 19:00

The numbers in the answers are access-list numbers, not item-list numbers.

- Access list 3 matches IP address A. The first three bits of 64 and 92 are zero, one, and zero.

- Access list 5 matches IP address B. The first three bits of 192 and 198 are one, one, and zero; the last bit of 94 and 0 are zero.

- Access list 2 matches IP address C. The first four bits of 48 and 50 are zero, zero, one, and one.

- Access list 4 matches IP address D. The first three bits of 128 and 144 are one, zero, and zero.