Implementing Content-based Publish/Subscribe with OpenFlow

Content-based publish/subscribe is a versatile communication
mechanism for building loosely coupled distributed applications.
In the past, publish/subscribe systems often required an overlay
network of cooperating brokers that inspect the content of a published
notification on the application layer in order to flexibly
make forwarding decisions. Leveraging OpenFlow-enabled network
switches, forwarding decisions can now be flexibly taken
within the network layer significantly reducing latency and jitter.