active network abstraction

What is a “Controller”? And how many do we need?

Thanks to SDN, the “Controller” word pops up in many network architecture discussions these days. In networking alone, we’re already surrounded by many “controllers” and we’re busy introducing more as we speak:  For example, Session Border Controllers or Wireless LAN Controllers have been around for quite some time, and have recently announced the OpenDaylight Controller, […]

The onePK Software Architecture

This post is about the onePK software architecture, and how it allows us to consistently expose network operating system (NOS) features to a wide variety of programming environments for IOS, IOS-XE, IOS-XR and NXOS. For an overview of onePK in general, and some more context, see my October 2012 post and my slides in Slideshare. The main elements […]