Software-Based Burst Mode Reception Implementation for Time-domain Wavelength Interleaved Networks

International audienceWe demonstrate burst mode functionality on a continuous commercial receiver piloted by real-time control plane in an end-to-end sub-wavelength switching test-bed. The results show the receiver can maintain its continuous performance with marginal penalty regardless of data burst absence duration. Introduction Switching sub-wavelength entities inside the big pipes channels appears as a promising solution for the operator that has to build a network with an efficient filling and different services. Access to the sub-wavelength granularity directly at the optical layer is an alternative to electrical solution to reduce cost and power consumption by saving on electrical transit and electrical-to-optical and optical-to-electrical conversions. Amongst the various Sub-Lambda Photonically Switched Network (SLPSN) solutions, Time-domain Wavelength Interleaved Networking (TWIN) is an interesting solution since it provides optically transparent sub-wavelength grooming at intermediate/core nodes, while the intelligence and processing power remains at control plane and the edge node

Multi-Granular Optical Cross-Connect: Design, Analysis, and Demonstration

A fundamental issue in all-optical switching is to offer efficient and cost-effective transport services for a wide range of bandwidth granularities. This paper presents multi-granular optical cross-connect (MG-OXC) architectures that combine slow (ms regime) and fast (ns regime) switch elements, in order to support optical circuit switching (OCS), optical burst switching (OBS), and even optical packet switching (OPS). The MG-OXC architectures are designed to provide a cost-effective approach, while offering the flexibility and reconfigurability to deal with dynamic requirements of different applications. All proposed MG-OXC designs are analyzed and compared in terms of dimensionality, flexibility/reconfigurability, and scalability. Furthermore, node level simulations are conducted to evaluate the performance of MG-OXCs under different traffic regimes. Finally, the feasibility of the proposed architectures is demonstrated on an application-aware, multi-bit-rate (10 and 40 Gbps), end-to-end OBS testbed

First experimental demonstration of real-time orchestration in a Multi-head metro network

International audienceWe present for the first time the experimental demonstration of a Real-Time control-plane on the Multi-hEad sub-wavElength swiTching (MEET), Metro architecture. The key control assets are calculated and provided to the edge nodes in a form of grant files. These grant files eliminate the contention possibility at source nodes and destinations, thus they offer a lossless passive optical grooming and multiplexing/demultiplexing at the intermediate nodes. The experimental results validate the control plane structure designed based on a deterministic operating system well scalable for a regional metro network

Contribution à la conception d'un réseau d'agrégation optique

This thesis aims at proposing a transparent optical architecture for metropolitan area networks. This multi-service architecture allows supporting both unicast and multicast tra¿c and o¿ers a performance suitable for metro networks. The approach that we followed was based on an optical packet ring concept. The ¿rst contribution of this thesis is a complete MAC, which is based on labels allowing identifying the di¿erent ¿ows in order to handle then with dedicated mechanisms. Then, we propose original fast protection mechanisms, both for unicast and multicast. The protection type can be speci¿ed for each ¿ow. In the last part of the thesis, we consider architecture based on the combined use of optical circuit and packet switching, in order to provide several levels of granularity while o¿ering end-to-end transparency.Le but de cette thèse est de proposer une architecture optique transparente pour les réseaux métropolitains. Cette architecture est multi-service, supporte unicast et multicast, et o¿re une performance en matière de protection compatible avec les besoins d¿un réseau de transport. Les travaux s¿appuient sur la notion d¿anneau de paquets optiques. La première contribution de la thèse est une MAC complète, basée sur l¿utilisation de labels permettant d¿identi¿er les ¿ots et de leur appliquer des traitements di¿érenciés. Dans une seconde partie, des mécanismes originaux de protection sont proposés, à la fois pour l¿unicast et le multicast. Le niveau de protection peut être spéci¿é pour chaque ¿ot. Une dernière partie propose de considérer simultanément commutation de circuits et de paquets optiques a¿n de supporter plusieurs niveaux de granularité tout en o¿rant une transparence de bout en bout

Resilience in Transparent OPS Multi-Rings

International audienceThis paper presents a resilient multi-ring network architecture based on the ECOFRAME technology. Each ring network is made of two unidirectional transparent WDM optical packet switched rings, each with a separate control channel synchronized with one or several data channels. Two rings networks are interconnected by two adjacent nodes in order to ensure resilience. Such a multi-ring network is a good candidate for replacing the current SDH multi-ring metro networks as it presents many features of a Transport Network. Contrarily to existing Ethernet rings or RPR networks, it is fully optically transparent within one ring, and may not access the client layer at interconnecting nodes, which allows provisioning client layers only at the edges of this network. A multi-class label-based MAC is proposed, and resilience mechanisms for both unicast and multicast transport are proposed

Reliable Multicast on a WDM Optical Packet Ring

International audienceThe present paper addresses multicast protection in WDM Optical Packet Rings that are currently considered for future metro network architectures. The considered architecture is optically transparent for transit traffic, which drastically limits the number of OEO conversions compared to e.g. Ethernet Packet Rings. WDM Optical Packet Rings offer huge capacity while still retaining a packet based granularity, which is not the case for ROADM based networks. Metro networks now support multicast, as IPTV services are largely deployed. Two alternate methods for implementing the traditional 1+1 and 1:1 protection mechanisms are proposed. Both rely on using the time slotted control channel to deliver failure and recovery information. The performance of the two methods are thoroughly assessed and it is shown that the transient degradation durations are always bounded by the Ring Round Trip Time, which is at least an order of magnitude less than the usual 50ms target time for protection. Moreover, using a Multicast Drop-off Middle Point is shown to provide an almost loss free transport in case of single failure. Lastly the single ring protection schemes are extended to multi-ring architectures, relying on an MPLS-TP compatible operation mode of the WDM optical packet rings

Rapid Protection Schemes in an All-Optical Packet Metro Ring

International audienceThis study adapts the two conventional protection methods, 1+1 and 1:1, to an all-optical, time-slotted packet ring designed for metropolitan area networks. The two correspond- ing protection schemes, Premium and Regular, rely on OAM messages that can be carried in each time slot. Each scheme offers packet level protection and maintains a congestion free and simple recovery mechanism in case of single failure. The upper bound for failure recovery time is very low as it is limited to the ring cycle time, which is about 2ms (much less than the 50ms SDH recovery time). The results suggest two very robust and efficient protection methods. In premium method network experiences no loss, whereas the loss period for Regular traffic is limited to a portion of the Round Trip Time. Preliminary dimensioning results are obtained under the assumption that the ring is dimensioned to support a single link failure. The difference between resources for Premium and Regular schemes depends on the traffic matrix and may be negligible for the very common concentration/distribution scenario. In the uniform traffic case, the cost of a dual ring with Regular protection is shown to be very close to the cost of a single, unprotected ring

Fully transparent design of a hybrid optical packet/circuit metropolitan area network

International audienceWe present a new method to design a regional network based on optical hybrid packet and circuit switching. Our approach aims at providing packet-level grooming only where it is profitable. The method relies on splitting the original traffic matrix in two parts, which will be transported either through optical packets or through circuits, according to a maximum wavelength capacity threshold. The network dimensioning can be then performed for circuit and packet traffic matrices separately. As the circuit WDM network design problem is well documented, we put the emphasis on the optical packet network dimensioning. This later is performed in the context of Packet OADM (POADM) technology, involving fast tuneable emitters and receivers dedicated to specific wavelengths. First, candidate sets of rings are identified. Then, the resources needed for each ring of a given set are evaluated by taking into account both receiver and wavelength costs. The "wavelength cost" depends on the considered ring, as it is proportional to its circumference. A linear programing formulation, previously established for unidirectional rings, is adapted to bi-directional ones with shortest distance routing and 1+1 protection. The proposed method is applied to a 7 nodes network by considering different scenarios in terms of content-delivery node positions, wavelength capacity threshold or network geographical extension. Even if most of the traffic is carried by circuits, POADM technology is widely used as a grooming technique across the network. The benefits of using POADM technology are achieved without necessitating O/E/O conversions at packet ring interconnections and alleviating inter-ring synchronization issues, resulting in a fully transparent network

QoS of Optical Packet Metro networks

International audienceMetro networks support increasing traffic volumes and evolving traffic profiles. Revisiting metro networks architecture, this paper shows that both optical transparency and sub-wavelength granularity can be achieved, while still ensuring transport network QoS levels