A regenerative optical grooming switch for interconnecting 100 Gbit/s networks with lower bit-rate networks and
switching functionality in time, space and wavelength domain is demonstrated. Lab and field demonstrations show the
feasibility of the new concept. Q-factors above 20 dB are reported.
Optical packet switching is commonly considered as a possible technology for future telecommunication networks, due to its compatibility with bursty traffic, eg Internet protocol (IP), and efficient use of wavelength channels. Current transport networks are voice-optimised and connection oriented, however the amount of data traffic is rapidly increasing, resulting in a continuous increase of average traffic through major exchanges exceeding 30% per annum (in Europe). Thus optical packet switching is seen as a future technology that will support diverse traffic profiles and give more efficient bandwidth utilisation through its ability to provide multiplexing at the packet level. In recent years the significance of optical packet switching as an emerging technology has been identified and researched by a number of research groups. Earlier optical packet switching demonstrators presented switching of mainly ATM compatible synchronously transmitted packets at bit rates up to 2.5b/s with the optical header encoded either in series or in parallel to the payload using the sub-carrier modulation technique. More recent projects have demonstrated switching capabilities at 10Gb/s using more advanced approaches with special encoding schemes for header and header detection, together with sophisticated control mechanisms for contention resolution. The capability of switching optical packets at bit rates up to 160Gb/s has recently been demonstrated. This paper discusses the architectures currently proposed for high speed optical packet switching, including the key techniques of header processing and payload switching. The focus is on a high speed demonstrator [OPSnet] capable of operation at rates >100 Gb/s.
A new generation of scientific applications is emerging that couples scientific instruments, data and highend computing resources distributed in a global scale. Developed by collaborative, virtual communities, many of these applications have requirements such as determinism (guaranteed QoS), shared data spaces, large data transfers, that are often achievable only through dedicated optical bandwidth. High capacity optical networking can satisfy bandwidth and latency requirements, but software tools and frameworks for end-to-end, on-demand provisioning of network services need to be developed in coordination with other resources (CPU and storage) and need to span multiple administrative and network technology domains. In response to the above requirements, this paper will address some of the key technical challenges to enable on-demand e2e network services. The proposed network concept will make applications aware of their resources (computational and networking) environment and capabilities, and able to make dynamic, adaptive and optimized use of network infrastructures connecting various high-end resources.
A detailed study of distributed Raman amplification using a bi-directional pumping scheme is investigated in this paper. In the final part we present an unrepeatered transmission experiment with the use of distributed Raman amplification and key results are discussed.