The NORDUnet Network

The NORDUnet Network

NORDUnet operates an optical network backbone interconnecting Oslo, Stockholm, Helsinki, Copenhagen, Hamburg, Amsterdam, and London. This network forms the northern extension of the GÉANT footprint, and through cross-border fibre connects to Poznan, St. Petersburg, and Tallinn.

In addition, NORDUnet operates an MPLS fabric used for IP network services and settlement-free peering. The MPLS fabric has nodes in the five Nordic capitals, in Amsterdam, London, and Frankfurt, as well as at five locations in North America. Operating an independent, international network allows NORDUnet to effectively manage cost of IP transit and at the same time offer attractive, high-quality Cloud-based services in a fully controlled network environment.

The IP network is dual stack IPv4 & IPv6.

The NORDUnet IP and MPLS network

NORDUnet operates a global IP and MPLS backbone network that interconnects the research and education networks in the Nordic countries to the rest of the world.

In Europe, the IP & MPLS network is built on top of the NORDUnet optical network, and shares the same locations.  In addition, it has a ring central Europe, connecting Frankfurt and Geneva to Hamburg and Amsterdam.  This ring is based on capacity obtained from partner European R&E networks SURFnet and PSNC.

Peering infrastructure

To secure the best possible commodity internet service for the Nordic research and educational networks NORDUnet A/S operates a global IP network and is currently present at the following Internet eXchange points:

    • Europe
        • AMS-IX in Amsterdam
        • NL-IX in Amsterdam
        • Asteroid International in Amsterdam
        • DIX in Copenhagen
        • NETNOD in Copenhagen
        • INEX Dublin
        • DE-CIX in Frankfurt
        • ECIX in Frankfurt
        • ECIX in Hamburg
        • FICIX Helsinki
        • LINX in London
        • LONAP in London
        • NIX in Oslo
        • RIX in Reykjavik
        • NETNOD in Stockholm
        • STHIX in Stockholm
    • North America
        • Equinix in Ashburn (Washington D.C.)
        • Equinix in Chicago (IL)
        • NYIIX in New York
    • Asia
        • HKIX Hongkong
        • SGIX Singapore

See more info about NORDUnet (AS2603) in

Peering requests should be sent to

DiffServ Support

The NORDUnet backbone supports the use of DiffServ and will not touch codepoints used by DiffServ. However, no active measures are taken to support DiffServ-based QoS implementations such as Premium IP. The NORDUnet backbone does not grant traffic priority, but it does allow the transport of for example Premium IP traffic between peering partners.

Looking glass

NORDUnet looking glass allows you to ping and traceroute from NORDUnet routers.

Communities and Blackhole

NORDUnet has established a bgp blackhole community.
Prefixes marked with 2603:999 will be remarked towards our upstream providers and will therefore also be blackholed before it enters NORDUnet

The following communities are available in NORDUnet for usage by all IP transit customers. These communities can be applied on prefixes (v4 + v6) advertised towards NORDUnet.

Announcement control communities:

  • 2603:664 Do not advertise to Commodity (transit)
  • 2603:665 Do not advertise to Commodity and non-Nordic Peerings.
  • 2603:666 Do not advertise to Commodity and Peerings.
  • 2603:667 Do not advertise to non-NORDUnet-member R&E.
  • 2603:668 Only advertise to GEANT R&E sessions and nothing else

Blackhole communities: 2603:999, 2603:998

  • Prefixes tagged with community 2603:999 will be blackholed. All NORDUnet edge routers will discard traffic sent towards the tagged destination.
  • Prefixes will also be forwarded to upstream with the corresponding blackhole community.
  • You can only tag your own prefixes with this community.
  • You can only tag more specific / longer prefixes then what NORDUnet filters on. This means that if your aggregate for example consists of a /16 to NORDUnet, the maximum prefix length you can blackhole is a /17.
    This constraint was put in place to avoid mayhem if someone  accidentally tags their aggregate with the blackhole community.
  • Prefixes tagged with community 2603:998 will be blackholed outside of the Nordics. Traffic will still flow in routers in Iceland, Denmark, Norway, Sweden and Finland. Otherwise, the same constraints apply.