You can use the BETWEEN operator in the where condition of your report. Do note you will have to use the tblAssets.IPNumeric table and write the IP addresses in full without dots as shown below. You can find more information about the BETWEEN operator here: https://www.w3schools.com/sql/sql_between.asp
The example will show all assets in the 192.168.1.1 - 192.168.1.50 IP range
Where tblAssets.IPNumeric
Between 192168001001 And 192168001050