This attribute specifies the node portion of the IPX address of the service
to be filtered from SAP packets. The node number can be entered either
as a dashed hex string or a string of hex digits entered in pairs of hex
digits up to a maximum length of 12 digits.. (For example a valid node
number would be ff-ff-ff-ff-ff-ff or ffffffffffff). A node number preceded
by a caret (^) should be interpreted as filtering all SAP packets except
for the ones with this node number.