By Dr. Ioannis Tomkos
OFC traditionally focuses on innovations associated with novel photonic devices and subsystems, as well as associated system/network demonstrations. However over the past few years the participants have clearly observed a significant shift in the topics covered by the conference sessions. The applicability and usefulness of advanced electronics in optical communication systems and networks has become evident through a large number of presentations that are focusing on advancements associated with electronic signal processing, FPGAs and ASICs. In addition, there is an increasing number of papers talking about software-related topics, such as algorithms for improved signal clarity, network performance optimization, network control and management, among other areas. Finally there are more and more papers that go beyond fiber-optics and examine the applicability of photonics in datacom/computercom applications, as well as in free-space wireless systems for in-building or/and access & metro networks. As a result of the aforementioned facts, a sizeable number of presentations are dedicated to such topics and the associated research problems.
OFC is Multi-disciplinary
However the real innovations usually come from solutions that address holistically the multi-disciplinary nature of the research challenges. Therefore OFC attracts more and more experts from areas other than optics and photonics, including communications signal processing, information theory, software engineers and computer scientists. Several conference sessions and workshops are dedicated to such cross-disciplinary topics where a heterogeneous mix of participants, each with their own perspectives, tries to address a specific application area.
However, it is then inevitable for people having different backgrounds and orientations that eventually “do not speak the same language” and some terms get even “abused” as are used with different meanings each time! Typical examples of such misunderstandings relate with the use of the terms “software defined photonics” and “software defined networking”. Those terms refer to topics that are fundamentally different one from the other (besides the fact that they are both “software-defined”…), but they may be even used interchangeably by some people in an effort to define the same meaning more or less! In the following I try to clarify a bit the situation.
What is the Difference Between “Software Defined Photonics” and “Software Defined Networking”?
The term “software defined photonics” was “borrowed” by the wireless communications community that was using the term “software defined radio”. The term “software defined photonics” defines advanced photonic subsystems (e.g. transceivers) for which the hardware is versatile enough in order to enable reconfigurations of key subsystem parameters by the use of software (e.g. data rate, modulation format, FEC/payload ratio, multiplexing scheme and number of subcarriers forming a super-channel, etc. for the case of transceivers). On the other hand, the term “software defined networking” was “borrowed” by the packet networking community and defines the separation of the control plane from the forwarding plane and the programmatic control of the forwarding with the promise to enable eventually the converged control of packet and optical networks. However, as correctly pointed out by many people so far “SDN can mean different things to different people”, so we need to be careful about what it does and what its relationship with “software defined photonics” is! Of course the use of both “software defined photonics” and “software defined networking” can potentially benefit one another and one can be viewed as an enabler/catalyst for the other when they are applied in optical networks.
OFC Covers both “Software Defined Photonics” and “Software Defined Networking”
In fact all these issues about “software defined photonics” & “software defined networking” and their interdependencies, will be discussed extensively at the OIDA/OSA workshop “Software Defined Photonic and Data Center Networks” and the OFC workshops “SDN for Transport Networks”, “Does SDN Spell the End for GMPLS?” and “Software-Defined Optical Access: Hope or Hype?” that try to answer some really nice, simple but important questions (e.g. “What is the definition of SDN? Why does it apply to core transport or/and broadband access networks? What will it take to deploy SDN in transport and access networks? Does SDN need to interoperate with existing operational control planes? Should SDN control reach down to the photonics? Is SDN necessary? Is SDN Hope or Hype?”). The workshops promise to take away the “hype” associated with the popularity of those terms and will reveal the real benefits expected from their introduction in different network segments compared to the existing solutions (i.e. what “software-defined” photonic sub-systems offer compared to the “plain-old” “programmable” photonic subsystems, and what “software-defined networking” can add over the “plain-old” centralized PCE/GMPLS control plane).
In any case, it would be interesting to know what are your views about the topics of “software defined photonics” and “software defined networking”, what do they mean for you and which are the expected benefits from their introduction in the various application areas that OFC covers. I am looking forward for your relevant comments!
Dr. Ioannis Tomkos
(Dr. Tomkos has been involved with OFC/NFOEC in various roles ranging from participant and speaker to exhibitor, workshop organizer, committee member and subcommittee chair).
Ioannis Tomkos (B.Sc., M.Sc. Ph.D.), has been with AIT since September 2002 (serving as Professor, Research Group Head and Associate Dean). In the past he was Senior Scientist at Corning Inc., USA (1999 – 2002) and Research Fellow at University of Athens, Athens, Greece (1995 - 1999). He is also currently an Adjunct Professor at University of Arizona College of Optical Sciences and at University of Cyprus. Together with his colleagues and students he has authored over 500 peer-reviewed archival scientific articles, including about 150 journal/magazine/book publications and 350 conference/workshop proceedings papers. Dr. Tomkos was elected in 2007 as Distinguished Lecturer of the IEEE Communications Society for the topic of optical networking. He was also elected Fellow of the IET (2010) and Fellow of OSA (2012) for “outstanding scientific contributions to the field of transparent optical networking”.
Posted: 24 February 2014 by
Dr. Ioannis Tomkos
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