On Mon, Jun 20, 2011 at 1:56 PM, babu dheen <babudheen at yahoo.co.in> wrote: > > Hi, > > Can anyone explain what is DNS tunneling because i am seeing large number of DNS tunneling attack in IPS from one machine in the LAN. Did you try Google? First entry is very informative: http://www.dnstunnel.de/ -- Fajar