Google chief Internet evangelist and ACM president Vint Cerf believes that software defined networking (SDN) could benefit from some of the Internet's design flaws and lessons learned in creating the Internet. For example, open standards should be implemented, with differentiation stemming from branded versions of standard protocols rather than from patented protocols. Interoperability is essential for stable networks, and that requires standards, notes Cerf. As companies create SDNs, they also should take into account the successful design features of the Internet, including the loose pairing of underlying equipment instead of a heavily integrated solution, the modular approach, and open source technologies. However, he says SDNs can improve on the Internet's traffic routing, which now relies on sending packets to a physical port. Instead of this physical port, the OpenFlow protocol changes the destination address to a table entry, enabling a new type of networking that is better suited to the collaborative Web of the future. Another option could be content-based routing, in which the content of a packet determines its destiny. SDN's basic principal, dividing the control plane and the data plane, should have been incorporated into the Internet's design, Cerf notes. In the future, SDN could improve controlled access to intellectual property to help prevent piracy, and could bring together various existing networks.