The field type would need to be a text field because an IP address is a mixture of numeric and non numeric characters. Then you would need to develop a formula which calculates whether the IP address is in a valid format. Once you have that formula you can block the save either by using custom data rules or a form rule to let the user know that the IP address is not a valid format.
As for what that formula that would look like, first you would have to state what the rules are for a valid IP address and then if you're unable to write that formula a few of us could pitch in with ideas. But there is no built-in edit mask in need of QuickBase to validate a string meets the criteria of being a valid IP address.
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Mark Shnier (YQC)
mark.shnier@gmail.com
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