Hello Abinaya,

Welcome to the Monastery. Read this article CentOS 6 Repoforge (RPMforge) i386 perl-Net-SFTP-0.10-1.el6.rf.noarch.rpm it contains all the information that you need.

If in any case if there is an installation problem with the procedure please add more information where it is failing and we can take it from there.

Hope this helps, BR.