Deep-sea data transfer at the KM3NeT neutrino telescope

KM3NeT is a future cubic kilometre-scale neutrino telescope for the deep Mediterranean. Several hundred vertical detection lines, each containing up to 100 optical modules with photomultipliers will be anchored to a sea floor power and data transport network. Data acquisition will minimize offshore electronics, reducing difficult and expensive maintenance operations. No off-shore triggering or filtering combining signals from multiple optical modules is foreseen; all signals passing internal criteria (e.g. charge threshold) will be uploaded via a fibreoptic telecommunications cable at an overall data rate of~ 100Gb/s. Various options for front-end digitization and data transport, including colour multiplexing, are discusse