Start with two running Ubuntu 14.04 systems, which can be either VMs or physical machines. You’ll need a newer version of openvswitch than exists in Ubuntu 14.04, but you only need the user space components so this is easy. We’ll start by installing OVS 2.1.2 or later.
Log into one of your Ubuntu systems, and run:
OVS_VERSION=2.1.2 sudo apt-get install build-essential fakeroot debhelper libssl-dev wget http://openvswitch.org/releases/openvswitch-${OVS_VERSION}.tar.gz tar -xzf openvswitch-${OVS_VERSION}.tar.gz cd openvswitch-${OVS_VERSION} DEB_BUILD_OPTIONS='parallel=8 nocheck' fakeroot debian/rules binary cd .. sudo dpkg -i openvswitch-common_${OVS_VERSION}-1_amd64.deb openvswitch-switch_${OVS_VERSION}-1_amd64.deb sudo apt-get install mininet
Now, either run the same commands on the other system, or just copy the openvswitch-common and openvswitch-switch deb files over and install them, plus install mininet from apt.