A digital processing device with high input/output connectivity and modular architecture comprises a first plurality of input ports, a second plurality of output ports, and a third plurality of at least four basic elementary modules. The third plurality of the elementary modules is split up according to a partitioning of at least two sub-assemblies of module(s), at least two of which form different islets comprising at least two modules. The digital processing device comprises a harness of optical links for mutually interconnecting the sub-assemblies of modules whose interconnection lengths are compatible with interconnection runs between two interconnected islets which make it possible to avoid, by sidestepping, one or more items of equipment external to the digital processing device, and which are installed on a space platform and interposed between the two interconnected islets, or which make it possible to distribute at least two interconnected islets over two heat exchange zones of the space platform that are far separated by a separation distance on the scale of the size of the platform.