Ronny Lam


Juniper Is Taking a Hit on OpenFlow

Juniper published a new white paper today describing their alternative to SDN using their recent Contrail acquisition. One of the concerns I get from my customers is the investment that is needed with an SDN implementation. Juniper claims to be able to provide SDN-like functionality on existing hardware.

A great announcement of course, but what got my attention was the hit they take on OpenFlow…

The original approach to using OpenFlow is what we refer to as reactive end-to-end OpenFlow. Here, every first packet of every flow is punted to a centralized controller, which decides the end-to-end path for the flow and programs the flow into every switch on the path. This is not a scalable approach. Another more recent approach to using OpenFlow is to use it in combination with overlays. In this case, OF-Config is used to create overlay tunnels and openFlow is used to proactively install flows to steer packets into the tunnels. This is a reasonable way of using OpenFlow, although there are other approaches as well (e.g., XMPP) which are arguably even better because they work at a higher level of abstraction.