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A new end to end architecture based on Long-Reach Passive OpticalNetwork (LR-PON) with wireless integration, a distributed core built of opticaltransparency islands and an OpenFlow-based control plane, which is beingdeveloped in the EU project DISCUS, is described in this paper. The maintechnological advances and the network modelling and optimization approach arereported., QC 20140422

The nonlinear fibre loop mirror (NOLM) has been shown to be a versatile device for alloptical switching, ultrafast multiplexing/demultiplexing, logic applications, pulse shaping and passive mode-locking for fibre lasers. Initially, the NOLM devices were fabricated using polarisation-maintaining fibres due to concerns about polarisation stability. This can be particularly significant in self switching devices due to differential nonlinear polarisation rotation arising from the unequal powers in the counterpropagating signals. However, the use of polarisation-maintaining fibres is not attractive as coupler fabrication is difficult and a higher loss results when splicing to standard fibres. Recently, stable operation of a dual-wavelength NOLM ultrafast multiplexer/demultiplexer has been demonstrated using 6.4 km long standard telecommunication fibre. In this paper we present experimental results on nonlinear polarisation effects in a self-switching NOLM fabricated from a standard telecommunication fibre., This article is from 'OSA Proceedings of the Topical Meeting on Nonlinear Guided-Wave Phenomena Held in 2-4 September 1991. Cambridge, England United Kingdom. Volume 15', AD-A253 471, p357-361.

In a recent paper we demonstrated an all-optical demultiplexer using a nonlinear optical loop mirror (NOLM) in which a signal at one wavelength is used to switch a signal at a different wavelength. The switching signal in that case was generated from a mode-locked Nd-YAG laser at 1.32um operating at 76 MHz and the switched signal was a gain switched DFB laser operating at 1.56um at 1 GHz. The purpose of this present work is to extend the optical switching into the gigabit regime while, at the same time, avoiding high power laser systems.

We have recently reported on the generation of pulses as short as 1.2 ps from a mode-locked erbium fibre laser pumped by a frequency doubled Nd:YAG laser. Experimental and theoretical evidence strongly supported the idea that soliton pulse shaping played a dominant role in the short pulse formation. In this paper, we review this earlier work and present preliminary data from a simple, compact totally integrated erbium fibre soliton laser pumped by a high-power laser diode., This article is from 'OSA Proceedings of the Topical Meeting on Nonlinear Guided-Wave Phenomena Held in 2-4 September 1991. Cambridge, England United Kingdom. Volume 15', AD-A253 471, p136-139.

In recent work, we have studied the the shaping of picosecond-duration optical pulses by the intensity-dependent transmission characteristics of a nonlinear fibre loop mirror. We demonstrated both experimentally and theoretically the advantages to be gained from this pulse shaping, in particular pulse compression and pedestal suppression. In this paper, we report on a Nonlinear Amplifying Loop Mirror (NALM) which performs both amplification and intensity filtering functions. We believe that this work will be of significance to all-optical transmission systems and to some of the novel erbium fibre soliton laser configurations now being investigated., This article is from 'OSA Proceedings of the Topical Meeting on Nonlinear Guided-Wave Phenomena Held in 2-4 September 1991. Cambridge, England United Kingdom. Volume 15', AD-A253 471, p56-59.

Considerable effort has been devoted to the development of all-optical switches in the last several years, with a view to using these switches in ultrafast telecommunications. In spite of having a very low nonlinear refractive index coefficient (n2 = 3 x 10-20 M2/W), fused silica fibre is probably the best material medium for such switches owing to its extremely low loss (approximately 0.2 dB/km). A severe challenge in using fused silica fibre is designing devices that can take full advantage of the low loss property, since the device length needs to be maximised in order to minimise the switching power. The nonlinear optical loop mirror (NOLM) has proved to be very effective in this respect, and devices as long as 9km have been successfully tested by our group. The NOLM operates on the principle of nonlinear interference between counterpropagating modes of a single fibre. In this letter we report successful all-optical switching with a device which also allows long lengths of fibre to be utilised., This article is from 'OSA Proceedings of the Topical Meeting on Nonlinear Guided-Wave Phenomena Held in 2-4 September 1991. Cambridge, England United Kingdom. Volume 15', AD-A253 471, p349-352.