Open vSwitch Virtual Networking (OVN) augments Open vSwitch by adding SDN constructs of logical switches, routers, and ACLs to simplify the OVS Neutron integration.
The neutron-l3-agent implementation with the Linux IP stack and iptables to provide L3 services and overlapping IP address support by using the Linux network namespace has performance bottlenecks in some deployment architectures. The addition of the Linux Bridge between instances and the br-int bridge to support security groups using iptables introduces performance penalty. Refer to http://openvswitch.org/support/slides/OVN-Vancouver.pdf for details.
OVN aims to improve the scalability and performance by supporting IPv4 and IPv6 natively in the OVS. OVN implements a flow cache to provide a performance boost. OVN implements firewalls natively as flows in OVS using the Kernel conntrack module directly from OVS. Communication is via database updates to the ovsdb database, reducing the...