Advanced DWDM Nodes in CESNET2 Optical Network

CESNET2 is one of the first wide-area optical networks in the world, where the most advanced multi-way DWDM technology is implemented to maximize the transmission capabilities. The implementation of a Degree-4 ROADM node with three optical chassis enables remote software-switching of particular wavelengths in the direction of the given chassis connection, without any manual intervention.

The CESNET2 network boasts with over 1,500 km of fibers, that deploy the DWDM (Dense Wavelength Division Multiplexing) technology to maximize the throughput. WDM, in general, allows the transportation of multiple signals, each on different wavelengths, within a single optical fiber instead of just one flow. The existing DWDM system offers 32 independent wavelengths, each with a capacity of 10 Gbit/s. The wavelengths (lambdas) allocated to individual transmissions are multiplexed as needed in the ROADM (Reconfigurable Optical Add/Drop Multiplexor) nodes within the optical network. Thus it is possible to allocate bandwidth (transmission capacity) based on momentary requirements and to create logically independent networks over a shared optical infrastructure. Thanks to that, CESNET2 is able to support also "aggressive applications" typical for some research projects that require very short response times and need to transmit high data volumes, all without restricting any other concurrent application.

CESNET2 offers customized end-to-end transmission services on the level of optical fibers as well as the level of specific wavelengths. The modern DWDM implementation facilitates the integration of the optical infrastructure with the IP network toward a hybrid IP/optical network with dynamic optical path switching, providing services on various network layers depending on the specific needs of connected users. CESNET2 is going to gradually move onto the 40 and 100 Gbit/s transmission capacities, in line with the global development on the optical device market, and will continue its research efforts focused on DWDM and ROADM.

The CESNET association was founded by universities and the Academy of Sciences of the Czech Republic. The association is currently financed mainly from the resources of the governmental Committee for Research and Education and the resources of the association members. The association is engaged in the research and development of information and communication technologies, building and developing the national gigabit optical network, CESNET2, designed for research and educational purposes. With its research activities and accomplishments, the CESNET association can represent the Czech Republic in the European GÉANT2 project as well as other international projects.