The Mode-Gap project targets the 100 fold enhancement of the overall capacity of broadband core networks, and seeks to provide Europe with a lead in the development of the next generation internet infrastructure that will soon be desperately needed if we are to keep pace with societies ever increasing data-transmission requirements. It is now recognized that research results are within a factor of 2 of fundamental capacity limits, bounded by fibre nonlinearity and the Shannon Limit and radical approaches now need to be investigated if we are to avert grid-lock on the internet. Mode-Gap will develop multi-mode photonic band gap long haul transmission fibres, and associated enabling technologies. These fibres offer the potential of order of magnitude capacity increases through the use of multiple-input-multiple-output operation of the multi-mode fibre capacity and further order of magnitude capacity increases through the ultra low loss and ultra-low nonlinearity offered by multi-mode photonic bandgap fibre.Specifically MODE-GAP will:•\tDevelop ultra-low loss («0.1 dB/km) multi-mode (>10 modes) photonic band gap transmission fibre (MM-PBGF).•\tDevelop novel rare earth doped optical amplifiers for the new transmission windows necessary for the achievement of ultra-long links.•\tDevelop sources and detector arrays operating within the 1.8 to 2.1 um region•\tDevelop MIMO arrangements for coupling source arrays to multi-mode fibre and multi-mode fibre to detector arrays•\tDevelop MIMO and dispersion compensation signal processing algorithms applicable to both conventional solid core (glass and POF) fibres and MM-PBGF.MODE-GAP is therefore fully aligned with the objectives of ICT-2009.3.7 and directly addresses several of its target outcomes by developing "photonics technologies, components and (sub) systems driven by key applications/social needs" and using them to fulfil the EU vision of "future-proof networks and systems enabling unlimited bandwidth" enabling"more optical processing and very high spectral-density transmission and the reductionof power consumption at the system and component level" with the ultimate goal ofenabling "increasing information throughput". If successful, the MODE-GAP technologywill have a significant impact in enabling "future proof networks and systems" of"increasing information throughput". Without such a breakthrough the internet of thefuture will be severely compromised. The fundamental research needed to avoid this needs tobe undertaken now.