The NTFS directory is an index of file names. An NTFS index consists of 
index root, index allocation, and bitmap attributes. Each attribute is 
named "$I30", probably because it the index is for the attribute 30. The 
entries in the directory are ordered alphabetically. All entries are 
converted to upper case before sorting. Upper case is defined by the 
file $UpCase. Each entry can point to index buffer, which contains more 
entries that come before this entry. One artificial entry mark the end 
of an entry list. 