Fedora 21 workstation seems to come with a lot of virtualization features and most of the libvirt libraries installed. I only had to add the KVM virtual-manager which is the KVM application I am more familiar with. However, the new version of the libvirt* libraries have networking features that are great for the data centre environment, but maybe not the best option for a particular workstation, so I added the following packages in order to set up an easier network configuration for my local virtual machines.

sudo dnf install virt-install libvirt-daemon-config-network

In order to reflect the changes and start using the new features, we need to restart its service:

systemctl restart libvirtd.service

After that, when creating a new virtual machine, the NAT option is enabled, and the virtual manager with handle the NAT or bridging configuration automatically, which allows me to deploy new machines faster.