OpenStack Neutron
5.7#3 in virtual private cloud (vpc) softwareAPILinuxSelf-hosted
VisitOpenStack Neutron vs Rackspace Cloud Networks
Rackspace Cloud Networks
4.6#12 in virtual private cloud (vpc) softwareWeb
VisitPick OpenStack Neutron if…
Neutron is aimed at OpenStack administrators deploying and managing networking for instances. The guide's example is for users with sufficient Linux experience learning through a proof of concept.
Pick Rackspace Cloud Networks if…
You want what its maker publishes above — check its page for the details.