Three possible scenarios of Software Defined Networking (SDN)

Software-defined networking (SDN) is an approach to create a centrally controlled programmable packet network. Any protocols with the same approach could be considered as SDN as well.

For open protocols, we have one popular standard protocol “OpenFlow” talking among the central controllers to all managed networking devices. Open Network Foundation (ONF) defines OpenFlow protocol.

In fact, vendors also have developed proprietary protocols to implement this same approach. For example, Cisco’s ACI is a proprietary SDN solution.

Here I summarize 3 most probable scenarios when we deploy SDN.

Bandwidth (Throughput) is not everything about network performance

A look along the Coconut Palm Avenue (椰林大道).
National Taiwan University.

We like to compare the "bandwidth" numbers of different network systems. In my experience, bandwidth is the most asked property when I am introducing new technologies to other network workers. Bandwidth is very easy for people to understand, to do the calculations, and to compare which one is better than the others.

However, bandwidth is just not everything. Network with larger bandwidth is simply not a faster network at all.

Here I crafted an imaginary example, to show you why bandwidth is not as important as you might think of.

This imaginary example is called: "Trans-Pacific High Bandwidth Pipe".

Northbound, Southbound, and East/Westbound. What do they mean?

We hear a lot of directions when we are talking about Data Center technologies: Northbound, Southbound, and even Eastbound/Westbound. What do they mean? Why are they called this way?

Software Defined Networking (SDN)

Source: Wikipedia

For minimum discussion of SDN, three layers are defined inside an SDN. They are SDN Service Layer, Controller, and Physical Network.

Cisco APIC Enterprise Module provides SDN on existing Cisco routers and switches

Here is my understanding about this coming, new APIC Enterprise Module from Cisco Systems.