Software-defined networking (SDN) is still just emerging, and that's led to some intriguing and fun conversations with the people making it happen. There's certainly a lot to discuss, with the future seeming even more open-ended than usual, in some ways.

Here are five that I think stood out this year, some of them representing some noteworthy bits of news along the way. You can also click here for a full list.

Matt Davy, Tallac Networks (January 2013)

Davy had been one of the luminaries of SDN's early days, preaching the benefits of OpenFlow from his post at the University of Indiana. He provided an end-user's voice to SDN discussions, stressing that his network was no academic toy. It connected residences, fire stations, and a hospital. This was the network of a small service provider, and it was using OpenFlow.

At the start of 2013, Davy left the university and InCNTRE to join startup Tallac Networks. We used the opportunity to get his thoughts about the state of OpenFlow an SDN — an interview that could use a 2014 follow-up, come to think of it.

Christos Kolias, Orange Labs (July 2013)

We've been running a series of interviews that provide service providers' perspectives on NFV, including thoughts from Margaret Chiosi of AT&T and Chris Donley of CableLabs. Kolias, who spent the last couple of years scouting Silicon Valley's SDN landscape, helped get the NFV industry specifications group (ISG) started within ETSI. He kicked off our NFV series by explaining his hopes for the technology and how it relates to SDN (the latter being a topic that's still part of the NFV dialogue).

Neela Jacques & Jim Zemlin, OpenDaylight Project (November 2013)

Jacques made the jump out of VMware to become an open-source guy, being named OpenDaylight's executive director in November. He and Jim Zemlin — the Linux Foundation executive director, who'd temporarily been helming ODP — stopped by SDxCentral's office for a long chat about the what it takes to build and run an open-source community.

David Meyer, OpenDaylight Project (August 2013)

Our first detailed look into OpenDaylight came from Meyer, chair of the Technical Steering Committee. It might seem unfair to have OpenDaylight on this list twice, but given the controversy surrounding the group's formation and the level of knowledge that Meyer brings to the conversation, it seems apt to have given OpenDaylight some extra attention.

The On.Lab Crew (May 2013)

On.Lab is a nonprofit founded by SDN pioneers from Stanford University and U.C. Berkeley. Not surprisingly, given that gene pool, On.Lab drew quite a crowd at the Open Networking Summit in April, prompting SDxCentral to go check out what was going on over there. The result: this interview with Guru Parulkar (executive director), Bill Snow (vice president of engineering), and Larry Peterson (chief architect).

Little did we realize that seven months later, we'd be writing about its SDN controller, ONOS, blitzing the market, with On.Lab reportedly pushing for customer commitments by year's end. It could be the start of a major battle with the OpenDaylight Project and Juniper's OpenContrail. (Catch up with Roy Chua's analysis: "Controller Wars 2.0," Part 1 and Part 2.)