DE-CIX operates so-called route server systems (s. RFC7947 for a detailed description) to facilitate the exchange of BGP announcements between peers at DE-CIX. Each peer needs only to set up a BGP connection to the route server in order to receive the BGP announcements of all other peers having a BGP connection with the route server.
DE-CIX operates two route servers at each of its Internet Exchanges that are redundant to each other.
Route servers keep the number of necessary BGP sessions low for DE-CIX customers because you need only one BGP session to each of the route servers to receive the prefixes of all other route server users.
You can use BGP communities to tell the DE-CIX route servers to whom to announce (or not announce) your prefixes.
Incoming you can use filter lists on your own routers to decide what to accept (or not accept) from the prefixes the route servers announce to you.
For new connected networks, the route servers give a kickstart into peering as they receive all prefixes of all route server users without having to setup individual BGP peering sessions; one session to each of the two route servers is enough.
Route Server Guides for the exchanges
At the links below you can find the detailed route server guides for our locations: