Norberto Amaya

Experimental demonstration of an OpenFlow based software-defined optical network employing packet, fixed and flexible DWDM grid technologies on an international multi-domain testbed

Software defined networking (SDN) and flexible grid optical transport technology are two key technologies that allow network operators to customize their infrastructure based on application requirements and therefore minimizing the extra capital and operational costs required for hosting new applications. In this paper, for the first time we report on design, implementation & demonstration of a novel OpenFlow based SDN unified control plane allowing seamless operation across heterogeneous state-of-the-art optical and packet transport domains. We verify and experimentally evaluate OpenFlow protocol extensions for flexible DWDM grid transport technology along with its integration with fixed DWDM grid and layer-2 packet switching.

Introducing node architecture flexibility for elastic optical networks

A large number of factors generate uncertainty on traffic demands and requirements. In order to deal with uncertainty optical nodes and networks are equipped with flexibility. In this context, we define several types of flexibility and propose a method, based on entropy maximization, to quantitatively evaluate the flexibility provided by optical node components, subsystems, and architectures. Using this method we demonstrate the equivalence, in terms of switching flexibility, of finer spectrum granularity, and faster reconfiguration rate. We also show that switching flexibility is closely related to bandwidth granularity. The proposed method is used to derive formulae for the switching flexibility of key optical node components and the switching and architectural flexibility of four elastic optical node configurations. The elastic optical nodes presented provide various degrees of flexibility and functionality that are discussed in the paper, from flexible spectrum switching to adaptive architectures that support elastic switching of frequency, time, and spatial resources plus on-demand spectrum defragmentation. We further complement this analysis by experimentally demonstrating flexible time, spectrum, and space switching plus dynamic architecture reconfiguration. The implemented architectures support continuous and subwavelength heterogeneous signals with bitrates ranging from 190 Mb/s, for a subwavelength channel, to 555 Gb/s for a multicarrier superchannel. Results show good performance and the feasibility of implementing the architecture-on-demand concept.

Software defined networking (SDN) over space division multiplexing (SDM) optical networks: features, benefits and experimental demonstration

We present results from the first demonstration of a fully integrated SDN-controlled bandwidth-flexible and programmable SDM optical network utilizing sliceable self-homodyne spatial superchannels to support dynamic bandwidth and QoT provisioning, infrastructure slicing and isolation. Results show that SDN is a suitable control plane solution for the high-capacity flexible SDM network. It is able to provision end-to-end bandwidth and QoT requests according to user requirements, considering the unique characteristics of the underlying SDM infrastructure.

Gridless optical networking field trial: Flexible spectrum switching, defragmentation and transport of 10G/40G/100G/555G over 620-km field fiber

We report the first gridless networking field trial with flexible spectrum switching nodes over 620 km field fibre links. Successful transport, spectrum switching and defragmentation achieved for mixed line signals including 555G and coherent 100G.

Fully-elastic multi-granular network with space/frequency/time switching using multi-core fibres and programmable optical nodes

We present the first elastic, space division multiplexing, and multi-granular network based on two 7-core MCF links and four programmable optical nodes able to switch traffic utilising the space, frequency and time dimensions with over 6000-fold bandwidth granularity. Results show good end-to-end performance on all channels with power penalties between 0.75 dB and 3.7 dB.

Architecture on demand for transparent optical networks

We present the Architecture on Demand (AoD) concept whereby transparent optical cross-connects (OXC) do not have an associated static architecture but can adapt their architecture to suit to the switching and processing requirements of input traffic. The proposed AoD-OXC is implemented with a 96×96 3D-MEMS optical switch functioning as an optical backplane that interconnects architecture-building modules that provide the required services such as arbitrary spectrum switching, time-domain sub-wavelength switching and optical multicasting. This approach will enable unprecedented levels of flexibility and modularity for the introduction of new services and applications in transparent optical networks.

Time shared optical network (TSON): A novel metro architecture for flexible multi-granular services

This paper presents the TSON metro mesh network architecture for guaranteed, statistically-multiplexed services. It proposes tunable time-wavelength assignment, one-way tree-based reservation and node architecture. Results demonstrate high network efficiency, fast service delivery and guaranteed QoS.

Experimental demonstration of a gridless multi-granular optical network supporting flexible spectrum switching

A gridless dynamic multi-granular optical network supporting flexible spectrum allocation is proposed and experimentally demonstrated to efficiently accommodate high-speed traffic and increase channel density for lower speed traffic leading to improved network efficiency and scalability.

Finding the target cost for sliceable bandwidth variable transponders

Elastic optical networking (EON) is a solution that promises to improve infrastructure utilization by implementing flexible spectrum allocation with small spectrum slots instead of the rigid 50 GHz fixed grid of current dense wavelength division multiplexing deployments. This new EON flexible grid supports bandwidth variable transponders (BVTs) that can tune their bit rate and bandwidth dynamically with a trade-off between reach and capacity. However, when BVTs need to transmit at low bit rates, part of their capacity is wasted. Therefore, the sliceable bandwidth variable transponder (SBVT) has been proposed, which can provide even higher levels of elasticity and efficiency to the network. SBVTs enable transmitting from one point to multiple destinations, changing the traffic rate to each destination and the number of destinations on demand. The aim of this work is to identify the target cost of 400 Gb/s and 1 Tb/s SBVTs to reduce, by at least 50%, transponder costs in a core network scenario. This target cost is calculated in relation to estimations for BVTs of 400 Gb/s and 1 Tb/s (non-sliceable). In light of our results, cost savings of 50% are feasible for 1 Tb/s transponders until 2020 with a higher cost than non-sliceable transponders. Savings of 50% for the 400 Gb/s case are possible in the short-term before 1 Tb/s SBVTs can appear in the market. Feasibility of such savings with a target cost higher than current non-sliceable transponders shows that SBVTs can be a reality. Moreover, this work assesses the IP port savings thanks to the utilization of the SBVTs.

Architecture on Demand: Synthesis and scalability

The optical cross-connect (OXC) is a key element in current WDM networks. In this context, the design of OXCs is becoming very challenging since it has to fulfil requirements from legacy optical networks and be future-proof to support both legacy lower bitrates and future high-speed super-channels by means of flexible allocation of spectral resources. In this paper we review the novel concept of Architecture on Demand (AoD) to dynamically synthesise architectures suited to the switching and processing requirements of traffic. We propose a technique suited to perform architecture computation and composition and discuss the scalability of the proposed technique. Results show that it is possible to reduce the number of hardware modules used at least by half compared to other conventional architectures.