The network discovery process is a great feature in Altiris, but you can only input ranges to include or exclude one at a time. The console does not have an option to allow you to enter a list of ranges. To get around this, right-click on the Network Discovery Policy and choose export. Save the XML file to your hard drive and open it with a text editor or an XML editor. Find the include IP or exclude IP range and just add additional ranges.
<include ip="1.1.1.1" endMask="1.1.1.255" type="range" /> <exclude ip="1.2.1.1" endMask="1.2.1.255" type="range" />