Olivier Audouin

Service level agreement and provisioning in optical networks

This article proposes a service level agreement applied to the optical domain (O-SLA), which is expected to be the near- and long-term network technology of the great bandwidth capacity offered by optical devices. After an exposition of the rationale behind an optical SLA, parameters that could be included in this O-SLA, as well as their values for four classes of services are proposed. Different client (wavelength or subwavelength) and service types (from leased wavelength to bandwidth on demand) are distinguished when necessary. The last part of this article presents issues related to the provisioning of services emanating from this O-SLA.

Synchronous in-line regeneration of wavelength-division multiplexed solitons signals in optical fibers

A new synchronization technique for simultaneous in-line modulation and regeneration of wavelength-division multiplexed (WDM) soliton signals in optical fibers is proposed. A specific wavelength-mapping rule makes synchronization compatible with frequency-guiding Fabry-Perot filters. As an example, a 4 x 10 Gbitys WDM regenerated soliton system is demonstrated numerically. We also show that the technique is fully compatible with dispersion management, which alleviates detrimental WDM collisions. Thus the possibility of combining wavelength-division multiplexing and regeneration opens up new perspectives for ultrahigh-bit-rate transoceanic soliton systems.

Dual-control nonlinear-optical loop mirrors for all-optical soliton synchronous modulation.

A novel dual-control configuration of nonlinear loop mirrors is used for all-optical soliton synchronous regeneration. Simulations show substantial improvement in transmission in this device compared with singlecontrol devices, owing to chirp-free modulation. The absence of chirp is confirmed experimentally through a spectral analysis of the dual-control modulator.

CARRIOCAS project: an experimental high bit rate optical network tailored for computing and data intensive distributed applications

CARRIOCAS project studies and implements in a test bed a very high bit rate (up to 40 Gb/s per wavelength) network tailored for distributed applications. The investigations covers 40Gb/s component, systems and networking; network architecture, protocols and algorithms with a particular focus on application-network cooperation; and remote high resolution collaborative visualisation and distributed storage of massive volumes of data.

From Network Planning to Traffic Engineering for Optical VPN and Multi-Granular Random Demands

In this paper, we investigate the routing problem for dynamic traffic demands providing differentiated types of service across the network. Two classes of traffic are considered: QoS traffic and best-effort traffic. We propose a comprehensive offline/online routing solution that enables service providers to satisfy the demands of customer traffic flows while respecting the traffic priority. As a first step, an offline global optimization tool is used for network dimensioning. It aims to minimize the number of optical and electrical ports required in the network in order to satisfy a given set of high priority demands. Once the networks nodes are dimensioned, the network can be over-dimensioned to carry additional best-effort traffic requests. The latter set of traffic is routed by means of an online sequential optimization tool. Low priority traffic are divided into two subsets according to the requested capacity of the demands. This capacity may correspond either to an optical channel data rate (lightpath demands) or to a fraction of that rate (electrical demands). Our sequential optimization tool proceeds automatically to the grooming of the electrical demands into grooming demands. The network performance is expressed as the ratio of the number of rejected/blocked requests to the total number of requests

Experimental demonstration of second-order average soliton propagation in an optical fiber over several soliton periods

The propagation of second-order average solitons in fiber loop with lumped amplifiers over several soliton periods is demonstrated experimentally and numerically for the first time to our knowledge. The numerical model gives the effect of the amplifier noise on the soliton stability, and the results agree well with the observations.

Network nodes dimensioning assuming electrical traffic grooming in an hybrid OXE/EXC WDM network

In this paper, one considers the routing and wavelength allocation problem (RWA) under deterministic dynamic traffic demands. Optical virtual private networks (OVPN) are typical examples of such demands. In previous papers, we have introduced the concept of scheduled lightpath demands (SLD) defined as a tuple (s, d, alpha, beta, omega). The parameters s and d stand for the source and destination addresses, alpha and beta are the setup and teardown dates of the demand, and omega is the required capacity expressed in number of optical channels. In this paper, we extend this concept to the case where omega is not an integer but a real value. In this context we introduce the concept of scheduled electrical demand (SED). For instance, a 3 Gbps demand, assuming 2.5 Gbps optical channels, corresponds to one SLD and one SED with 0.5 Gbps capacity. We propose a routing and grooming strategy based on a simulated annealing (SA) global optimization technique. Our objective is to minimize the number of optical and electrical ports required to satisfy a set of SLDs and SEDs on a given infrastructure. An original and realistic traffic model already introduced in previous papers is used for our simulations. We investigate for multiple traffic scenarios the geographical distribution of the size of the OXC/EXC nodes

Forward-error correction for time-slotted optical packets

We have shown that Reed-Solomon forward error correcting codes are best suited for optical packet as they are for optical circuit. However, due to their small size, a careful choice of the RS parameters has to be made. For instance, with our assumptions, standard RS(255, 239) code is not compliant with packets as short as 12,000 bits at 10 Gbit/s. RS(127,111) should be preferred.

Stability of synchronous intensity modulation control of 40-Gb/s dispersion-managed soliton transmissions

The efficiency of transmission control of dispersion-managed solitons by means of in-line synchronous intensity modulation is numerically analyzed. We demonstrate that intensity modulation may lead to dramatic improvements in the transmission performance of 40-Gb/s dispersion-managed solitons. In particular, we identify the locations within the dispersion map where synchronous intensity modulation provides an efficient control of the pulse propagation. Namely, a stabilization of pulse energy fluctuations is achieved, with no need for additional in-line control by guiding filters. On the other hand, incorrectly placed intensity modulation may cause significant pulse instabilities.

Demonstration of TMN management of a WDM network testbed

We have demonstrated configuration, fault protection, and performance management of a WDM network testbed. These experiments show the possibility to build a manageable client-independent optical transport layer, complying with current management standards.