OpenContrail architecture
The architecture of OpenContrail can be broken up into two main components:
vRouter
Controller
Let us examine each of these components in detail.
vRouter
The vRouter is the main component in the forwarding plane of OpenContrail. The vRouter runs on the Compute Nodes and acts as a virtual switch as well as a virtual router. It forwards the traffic to and from the virtual machines running on the Compute Node. Since OpenContrail is based on an overlay network architecture, the vRouter acts as the endpoint for overlay networks.
The vRouter is analogous to the Open vSwitch (OVS) when compared with an OpenDaylight-based SDN architecture. While OVS supports protocols like OpenFlow to program the forwarding plane, the vRouter uses XMPP as the control plane protocol. XMPP stands for Extensible Messaging and Presence Protocol. XMPP is an interesting choice for the control plane protocol. XMPP was designed as a protocol for detecting the presence and exchanging messages for real...