Do you know OpenFlow?

Is Openflow just an open interface to remotelly control switches and routers? Yes, but do you know what we can do with it? First of all we can separate the control part (OSPF,STPs,MPLS,BGPs...) and the data part ( Hardware part of the switches and routers). This means that all the boxes in the field will not have any complex programable part. Every one that setup a small network with one switch and onde router knows what does it means... Several lines of commands applied in different hardwares, operating systems using distinct protocols.

Separating the control and data planes you can have only one controller sending command to all nodes simultaneously. 

Besides separate planes,  there is a flow control that enables the administrator to send any information anywhere without being locked by the several layers invented in the past. There is no more packet or frame separation.

Receiving an information (I will never use terms like packets or frames as they makes no sense anymore)  in a port, the matching of desired fields will allow you to send it whatever you want.

Simple like IP "A" entered port 1. Sends it to port 20.  MAC address "Z" entered port 1?  Delete it. MPLS label entered port 20? Oppss I do not know what to do... Sends to the controller. He knows... If he doesn't send and alarm to the operator.

Ops, the operator is drinking coffee and this received information is congesting my port? No problem, block it and send an email to the parents of the operator. Too much coffee is dangerous for kids! 

Openflow enables us to create a domain of data (no more packet/frames) under one control and several "stupid box" located in field, it is a controled domain where any data can go to anywhere without the need to follow thousand of layers and protocols.

If you move to another town and is crying to reconfigure it all? Adding, removing boxes?  Just drag and drop it in your controller, save it in a fancy map and go for another coffee.

See you.

Claudio Couto