FreeTransit

It is not intended to provide a free upstream from which you build another transit service.

We explicitly disallow providing downstream transit using FreeTransit. FreeTransit routes must not be redistributed as Internet transit to additional downstream ASNs, and traffic from such downstream networks must not be sent towards FreeTransit as if they were part of your own network. Normal Internet peering is of course not the same thing as providing downstream transit.

We strongly discourage the increasingly common model where one hobby network obtains free or inexpensive connectivity from several tunnel brokers, IXPs and other hobby networks and then redistributes essentially the same connectivity to another collection of ASNs, which in turn repeat the same process.

Learning BGP, operating an ASN and experimenting with routing are exactly the kinds of things we want to enable. However, learning how to provide transit does not require every hobby ASN to become another public transit provider.

Repeatedly stacking transit services on top of tunnels and other free transit services does not meaningfully improve Internet connectivity or diversity. It often results in paths resembling:

end network → tunnel → hobby transit network → another tunnel → another hobby transit network → upstream

and sometimes several additional layers beyond that.

Each additional layer introduces another failure domain, another encapsulation and MTU boundary, another routing policy, and another operator who has to be involved when something breaks. It makes latency, packet loss, abuse handling and routing problems substantially more difficult to diagnose while frequently providing little actual path diversity because many of those networks ultimately rely on the same small set of free upstreams.

FreeTransit exists to help you connect and operate your own network. We do not want to encourage an indefinitely recursive hierarchy of free transit providers carrying the same connectivity through increasingly complicated tunnel topologies.

If your objective is to operate a downstream transit network and provide Internet transit to other ASNs, FreeTransit is not the appropriate upstream for that purpose.

We are also moving towards stricter source and reverse-path validation. Downstream traffic which does not comply with the FreeTransit routing policy should therefore not be expected to continue working simply because it happens to work today.