Kim, even if there is more than one octet you still can look at the number
of bits that are different. Example:

192.168.0.0
192.168.0.1
192.168.1.0
192.168.1.1

The above addresses have 2 bits (bit 0 in the 3rd and 4th octets) that
differ and we can combine them in one ACL.

3rd and 4th octets:
0000 0000 | 0000 0000
0000 0000 | 0000 0001
0000 0001 | 0000 0000
0000 0001 | 0000 0001

0000 0000 | 0000 0000 AND
0000 0001 | 0000 0001 XOR

192.168.0.0 0.0.1.1 would be the ACL entry.

-hth

Bryan Bartik
CCIE #23707 (R&S), CCNP
Sr. Support Engineer - IPexpert, Inc.
URL: http://www.IPexpert.com

On Mon, Jun 8, 2009 at 7:47 AM, Rodriguez, Jorge <
[email protected]> wrote:

>  Jeremy this should help you in doing the calculating  wildcard  mask
>
>
>
> http://www.internetworkexpert.com/resources/01700370.htm
>
>
>
>
> http://blog.internetworkexpert.com/2007/12/26/q-how-do-i-compute-complex-wildcard-masks-for-access-lists/
>
>
>
> Rgds
>
> Jorge
>
>
>
> *From:* [email protected] [mailto:
> [email protected]] *On Behalf Of *JEREMY FURR (RIT
> Student)
> *Sent:* Friday, June 05, 2009 10:12 AM
> *To:* [email protected]
> *Subject:* [OSL | CCIE_RS] ACL Wildcards
>
>
>
> Does anyone know of a website or book that explains well how ACL wildcards
> work? I have been trying to filter out four blocks from a bunch of route
> advertisments but just can't get the three I want through, this is what I
> have R2 is originating 192.168.2.0/24 through 192.168.15.0/24 in RIP to
> R1. I want to only accept blocks 192.168.5.0, 192.168.10.0, 192.168.13.0 and
> 192.168.14.0
>
>
>
> If I use acl with 192.168.10.0 0.0.4.0, I will get 10 and 14 but not
> thirteen. For the 5 network I just use the 192.168.5.0 0.0.0.255.
>
>
>
> Any thoughts or help would be appreciated.
>
>
>   Jeremy Furr [email protected]
>



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