curl to download packages from internet repositories.
I want use
axel instead of
curl to download packages: is it possible?
No. Yum calls curl directly (I believe through the library, not the executable). In any case, the update/install speed won't get better. If you are on Fedora, Fedora 18 has dnf as an experimental alternative to yum, it is much faster in resolving dependencies, and more accurate too. But it still has rather rough edges, and the tools around yum haven't been migrated. Both can be used (almost) interchangeably, in any case.