In the context of computer networking, a tunnel broker is a service which provides a network tunnel. These tunnels can provide encapsulated connectivity over existing infrastructure to another infrastructure.
There are a variety of tunnel brokers, though most commonly the term is used to refer to an IPv6 tunnel broker, as defined in RFC:3053, but it can also refer to an IPv4 tunnel broker. IPv6 tunnel brokers commonly provide IPv6 tunnels to sites or end users over IPv4. In general tunnel brokers offer so called 'protocol 41' or proto-41 tunnels. These are tunnels where IPv6 is tunneled directly inside IPv4 packets by having the protocol field set to '41' (IPv6) in the IPv4 packet. In the case of IPv4 tunnel brokers IPv4 tunnels are provided to users by encapsulating IPv4 inside IPv6 as defined in RFC:2473.
Read more about Tunnel Broker: Automated Configuration, NAT Issues, Dynamic Endpoints
Famous quotes containing the word tunnel:
“It is the light
At the end of the tunnel as it might be seen
By him looking out somberly at the shower,
The picture of hope a dying man might turn away from,
Realizing that hope is something else, something concrete
You can’t have.”
—John Ashbery (b. 1927)