Update process

[Dillenseger Eric]

Hi,
I'm trying to collect information about RH Entreprise Linux Update.
Our customers are often required to use RHEL Update2 to install their servers
but seem to get RedHat media base system without any update.
So my question is, how can I check with them if their media is suitable for
installation, and how can they get a bootable media containing an update
suitable for installation.
I found that Anaconda is used for updating a RedHat, but for a fresh install?
Thanks.