Subsystems for future access networks

Current evolution and tendencies of Telecom Networks in general and more specifically optical Metro and Access Networks and their convergence are reported. Based on this evolution, a set of research lines are foreseen regarding subsystems and devices as: high speed optical sources, modulators and receivers, for the next generation of Passive Optical Networks. The ICT project EURO-FOS is achieving European level cooperative research among academia and industry, enabling future telecommunication networks

Estimation of the OSNR penalty due to in-band crosstalk on the performance of virtual carrier-assisted metropolitan OFDM systems

The impact of the in-band crosstalk on the performance of virtual carrier (VC)-assisted direct detection (DD) multi-band orthogonal frequency division multiplexing (MB-OFDM) systems was numerically assessed via Monte-Carlo simulations, by means of a single interferer and 4-ary, 16-ary and 64-ary quadrature amplitude modulation (QAM) formats in the OFDM subcarriers. It was also investigated the influences of the virtual carrier-to-band power ratio (VBPR) and the virtual carrier-to-band gap (VBG) on the DD in-band crosstalk tolerance of the OFDM receiver. It was shown the modulation format order decrease enhances the tolerance to in-band crosstalk. When the VBG is the same for both interferer and selected signal, the interferer VBPR increase is seen to lead to lower optical signal-to-noise ratio (OSNR) penalties due to in-band crosstalk. Considering that the VCs frequencies of the selected and interferer OFDM signals are equal, the increase of the interferer VBG also gives rise to lower OSNR penalties. When the interferer and selected signals bands central frequencies are the same, the change of interferer VBG can attain 11 dB less tolerance to in-band crosstalk of the VC-assisted DD OFDM system. We also evaluate the error vector magnitude (EVM) accuracy of the in-band crosstalk tolerance of the DD OFDM receiver and our results show that the EVM estimations are inaccurate.info:eu-repo/semantics/acceptedVersio

Evaluation and experimental demonstration of SDN-enabled flexi-grid optical domain controller based on NETCONF/YANG

Flexible spectrum assignment in Elastic Optical Networks (EON) has emerged as a potential solution for allowing dynamic and elastic management of available bandwidth resources. In this paper, we demonstrate and evaluate our developed flexi-grid optical domain controller based on NETCONF/YANG. Our proposed modular architecture, based on Finite State Machines (FSMs), allows the flexibility to deploy the controller either in a centralized or in a distributed state for on the fly encrypted device management connections. A testbed composed of two physical Sliceable Bandwidth Variable Transponders (SBVTs) and an emulated flexi-grid optical network was used for our software evaluation. Controller startup and synchronization time, as well as media channel setup time are evaluated to compare the two deployment options and assess network scaling effects. Results demonstrate that our software is scalable by maintaining a relatively constant startup time on the networks tested (i.e., 1 to 64 nodes) in both deployment options. Software scalability is also supported by the media channel setup time, which presents a modest log scale growth when increasing the number of nodes from one to 64

Evaluation and experimental demonstration of SDN-enabled flexi-grid optical domain controller based on NETCONF/YANG

\u3cp\u3eFlexible spectrum assignment in Elastic Optical Networks (EON) has emerged as a potential solution for allowing dynamic and elastic management of available bandwidth resources. In this paper, we demonstrate and evaluate our developed flexi-grid optical domain controller based on NETCONF/YANG. Our proposed modular architecture, based on Finite State Machines (FSMs), allows the flexibility to deploy the controller either in a centralized or in a distributed state for on the fly encrypted device management connections. A testbed composed of two physical Sliceable Bandwidth Variable Transponders (SBVTs) and an emulated flexi-grid optical network was used for our software evaluation. Controller startup and synchronization time, as well as media channel setup time are evaluated to compare the two deployment options and assess network scaling effects. Results demonstrate that our software is scalable by maintaining a relatively constant startup time on the networks tested (i.e., 1 to 64 nodes) in both deployment options. Software scalability is also supported by the media channel setup time, which presents a modest log scale growth when increasing the number of nodes from one to 64.\u3c/p\u3

Optical label switched networks:laboratory trial and network emulator in the IST STOLAS project

This article reviews the performance of an optical-label-controlled packet routing node as implemented in the European FP5-IST STOLAS project including a set of general engineering rules. Experimental networking scenarios and results from a STOLAS based network emulator supporting optical overspill routing are presented

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We demonstrate all-optical label encoding and updating for an orthogonally labeled signal in combined IM/FSK modulation format utilizing semiconductor lasers, semiconductor optical amplifiers and electro-absorption modulators. Complete functionality of a network node including two-hop transmission and all-optical label swapping is also experimentally demonstrated with overall penalty of less than 2 dB, proving the orthogonal IM/FSK labeling scheme to be a feasible solution for future optically labeled networks

Real-time 10Gbps polarization independent quasicoherent receiver for NG-PON2 access networks

In this paper, we propose and test experimentally a real-time 10 Gbps polarization independent quasicoherent receiver for NG-PON2 access networks. The proposed 10 Gbps quasicoherent receiver exhibits a sensitivity of -35.2 dBm after 40 km standard single mode fiber (SSMF) transmission with a commercial generic EML as transmitter. This sensitivity means a 14.9 dB improvement over a direct detection scheme with a photodiode after 40 km SSMF transmission. Therefore, the use of the proposed 10 Gbps quasicoherent receiver with the tested EML will provide a power budget of 35.64 dB (class E2) and a splitting ratio of 128 after the 40 km SSMF transmission. Finally, the proposed 10 Gbps quasicoherent receiver allows a colorless and optical filterless operation because wavelength selection is done by tuning the local oscillator wavelength and using electrical intermediate frequency filtering