How do I BLOCK entire IP range as source in CISCO ASA5505 FIREWALL and ACL using SDM

I would like to block, i.e. deny access to an entire IP range as source in CISCO ASA5505 firewall and ACL using Security Device Manager (SDM).

I know how to block any individual IP using SDM, but I do not know how to define an entire range, for example: 100.100.0.0. up to 100.100.255.255.

Please look at the attached .jpeg figure.

Any help on specific steps to make using SDM interface, please?
Example-of-blocking-an-individua.jpg
Dr.Costas SachpazisGeotechnical & Structural Engineering Services.Asked:
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rauenpcConnect With a Mentor Commented:
A wildcard mask is essentially the reverse of a subnet mask. There are a lot of neat things you can do with wildcard masks that you can't do with a subnet mask, but most times you won't need to do the "neat" things.

For the most part, if you have a network/subnet, you can take each of the octets and change it to the difference of the subnet octet and 255.

So if you had a subnet of
255.255.255.0, the wildcard would be 0.0.0.255
255.255.252.0, the wildcard would be 0.0.3.255
255.255.0.0, the wildcard would be 0.0.255.255 (this covers your specific example)

to cover 100.100.0.0/16, the wildcard would be 0.0.255.255.
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rauenpcCommented:
The drop down menu for type (which in the picture is set to HOST/IP address) should have an option for network, subnet, or range. Selecting one of these options (I can't remember how the drop down is worked but it will be close) will then present you with a spot to type in both an IP address and a subnet mask. This will give you the ability to deny/ally and entire range of IP's.
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Dr.Costas SachpazisGeotechnical & Structural Engineering Services.Author Commented:
Thank you Rauenpc. I will have a look and I will let you know.
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Dr.Costas SachpazisGeotechnical & Structural Engineering Services.Author Commented:
So Rauenpc, as you can see in the attached figure, there is an option for "A Network", in the drop down menu.

Below that, there is a "Wildcard Mask" window, with a drop down menu, indicating specific and concrete addresses.... (as you can see in the attached image).

Therefore, if I want to block an entire range of IPs, for example: 100.100.0.0. up to 100.100.255.255, how in that case should I configure this interface?

Could you explain step by step?
Example-of-blocking-an-individua.jpg
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Dr.Costas SachpazisGeotechnical & Structural Engineering Services.Author Commented:
Thank you Rauenpc.

So, is that correct, as shown in the attached figure?

Remember, I want to block the entire range of IPs, from: 100.100.0.0 up to: 100.100.255.255.
Example-of-blocking-a-range-of-I.jpg
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Dr.Costas SachpazisGeotechnical & Structural Engineering Services.Author Commented:
Hello Rauenpc.

I am waiting for an answer from you, regarding wether this is correct or not, as shown in the previous attached figure?

Regards
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