A backbone IPv6 network connecting sixteen countries and running at 155 Mbps was established in 2002. This ran IPv6 over dedicated links, although for cost reasons, four links (to Greece, Hungary, Poland and Portugal) were provided by POS (Packet-over-SONET/SDH) over a Layer 2 VPN infrastructure.

Local access was provided through national IPv6 testbeds operated by partner NRENs (National Research and Education Networks) such as JANET (UK), RENATER (France) and SWITCH (Switzerland). Connectivity to the non-European 6NET partners in Japan and South Korea was provided via connections to London and RENATER respectively, and there are were connections to Abilene in the US (via SURFnet), Euro6IX (via the JANET- UK6X, GARR-TILab and SWITCHSwisscom exchange points) and to the 6Bone.

The 6NET backbone, and interconnected national testbeds, collectively formed the largest native IPv6 network in the world. This provided plenty of scope for trialling the new technology, testing interoperability with existing networks, and demonstrating services and applications. In fact, it demonstrated that the IS-IS and BGP4+ routing protocols, IPv6 over IPv4 tunnelling, and DNS support were stable and usable. In addition, a multicast overlay network (M6Bone) was established and has been utilised for conferencing and radio broadcasting (e.g., Trondheim Underground Radio).