Internal and external network communications are essential for CERN. Internally, over 50 000 km of optical fibre provide network connectivity throughout the CERN sites. The CERN Data Centre is also the host of the CERN Internet eXchange Point (CIXP), a carrier-neutral exchange point, through which CERN played a central role for the internet’s development. In 1991, 80% of the internet capacity in Europe for international traffic was installed in the CERN Data Centre.

One of the most impressive components of the Worldwide LHC Computing Grid is its networking and connectivity. It can initiate the distribution of data to the hundreds of collaborating institutes worldwide thanks to the excellent connectivity and dedicated networking infrastructure set up at CERN and subsequently worldwide. Since the beginning of the second four-year-long LHC running period, the data transfer rates around the globe also reached new peak rates – about 60 gigabytes per second rates, around a factor of three higher than had been typical during the LHC Run 1.