You can use the
yum downgrade [packagename]
command to downgrade any packages.
Check the yum log to see what you upgraded (networking related packages) and try to downgrade them.
The other option is to downgrade package is the
rpm -Uvh --oldpackage [filename]
So if you want to use the rpm then download the older version of the package and install it with the above command.
The different between the two is that rpm wont download any related dependency package if it's any and you need to do it manually one by one.
But yum will do the package dependency install automatically no matter if it's an upgrade or downgrade.