apt-get/aptitude

Many a times we mirror some iso-s of debian and put it on our laptops and/or local LAN to work as a repository. While installing it asks for authenicity of the packages.And we have to press/write 'Yes' all of the time. To get rid of this we can just write the following in /etc/apt/apt.conf

APT::Get::AllowUnauthenticated 1 ;

And please mind the spaces.