You can use quality of service (QoS) policies to guarantee or limit network bandwidth for egress and ingress VM traffic in different projects. QoS policies can be applied to separate network ports and floating IP addresses, as well as to entire networks. In addition, you can set a QoS policy as default for a project to automatically assign the policy to all new networks created within the project. The default QoS policy will be applied to a network if no other policy is explicitly assigned during the network creation process.
When you assign a policy to a network, all ports connected to this network inherit the policy unless the port has a specific policy assigned to it. The assigned policy is applied to both existing and new virtual machines. Internal network ports, like DHCP, and internal router ports are excluded from network policy application.