Kernel upgrade from version 701 to 720

Dear All,

Currently we have ECC 6.0 with EHP4  running on Windows server 2003+ MicroSoft SQL server  2005 database with Kernel 701 .

Now i am confused while upgrading kernel 720

I already downloded the sapexe 720 &sapexdb 720 from service market place.

I read some where we need to download SAPHOSTAGENT FILE also it will replace exsiting saposcol ,any one explain me the usage of saphostagent and how it will replace earlier saposcol.

I know  the procedure of upgrading upto 701 kernel .but i am confusing kernel720 procedure.

Please suggest the procedure arre same or not kernel 701 and 720.

Thanks