In 2012, an executive who worked for one of the largest European service providers shared his dream with the attendees of Layer123’s first software-defined networking (SDN) & OpenFlow World Congress in Darmstadt, Germany. According to him, the reason for all the misery in carrier-land were not permanent price battles, flat-rates, and cut-throat competition; it was us, the vendors.
We were accused of only offering hardware that was too expensive and wasn’t interoperable forcing carriers to pay much more than necessary. The audience was impressed — especially when we were asked to collaborate, define common interfaces, agree on one communication language, and offer open, fully programmable boxes based on standard industry architectures to drive his cost down as much as possible. For the majority of the audience, this might have been the first time when they were confronted with the realities of the new, open world. Since then, the world keeps on changing, but for some reason, both carriers and (most) vendors are still alive. But OpenFlow, the savior of that day, is virtually dead.
Well, quite a bit. It took a while, but people close to the matter realized that even after several massive iterations, OpenFlow would never be powerful enough for managing a dense wave division multiplexing (DWDM) system, let alone something as complex as a packet-optical transport system (P-OTS) or an optical transport network (OTN) switch. This didn’t stop some vendors from claiming that their transport solutions are fully compatible with this not so powerful language, so a lot of confusion was injected into our industry, but in reality it never worked.
The idea of one powerful controller, to control all network items, only worked in theory since it would hamper operations substantially due to the readily available compute power and lack of common standards. Over time, the dream of one language, one central controller, and flat, programmable networks became a playing field for marketing departments and clueless journalists. SDN, announced as the new messiah, went down from being the Holy Grail to becoming the next version of network management systems (NMS). Element management systems (EMS’s) are called Domain Controllers, NMS’s are Parent Controllers and Umbrella Network Managements (remember those?) are called orchestrators.
The full blog origianlly appears on sdxcentral: https://www.sdxcentral.com/articles/contributed/what-went-wrong-long-journey-open-networks/2016/11/