This map shows the locations of Internet Exchanges. At IX’s network providers do “peering ” (transfer of internet packets to be delivered by the peering partner on the basis of about equal traffic of both providers that do peering) and “transit”, meaning connection to/from long distance networks. It should be understood that IX’s are not switching points in the sense that failure of such a node would bring down part of the internet. No, by agreement network providers always have links bypassing the IX-s with their own backbone networks.
IX’s can be seen as big airports where travelers (packets) can do “transit” and “peering” between airlines or more local/regional modes of transport. Mutual benefit of IX’s is that it reduces “tromboning”, meaning the long distance data transport: up and down to&from a distant IX while the traffic is between local network providers or ISP’s. For instance peering between German network providers has been done at the AMS-IX in Amsterdam to save a lot of datatraffic otherwise up&down to New York.
The IX’s also provide neutral (non-competitive) peering points for non-internet traffic like voice traffic between mobile operators, TV video flows etc. The NDIX in NL and GER is a new type: a distributed (regional) IX with Points of Presence (can be seen as feeder airports) in more than 90 cities.
The four biggesr and fastest growing “hub” IX’s (actually located in several backup-ed locations in each city) in Europe are in: London, Paris, Amsterdam and Frankfurt.
The zoomable map (from 2016) can be seen at http://internetexchangemap.com/ The Internet Exchange Map is a free resource from TeleGeography. Data contained in this map was complied by TeleGeography and is updated on a regular basis.
The most recent update is from July 27, 2016 http://www.internetexchangemap.com/
jaap van till, TheConnectivist