This can be usable in different situations where internet access is firewalled, but DNS queries are allowed.

iodine runs on Mac OS X, Linux, FreeBSD, NetBSD and OpenBSD and needs a TUN/TAP device.

The bandwidth is assymetrical with limited upstream and up to 1 Mbit/s downstream.

The name iodine was chosen since it starts with IOD (IP Over DNS) and since
iodine has atomic number 53, which happens to be the DNS port number.

NOTE: iodine is licensed and distributed under the terms of the ISC license.

Here are some key features of "iodine":

· iodine uses the NULL type that allows the downstream data to be sent without encoding. Each DNS reply can contain nearly a kilobyte of payload data.
· iodine runs on many different UNIX-like systems. Tunnels can be set up between two hosts no matter their endianness or operating system.
· iodine uses challenge-response login secured by MD5 hash. It also filters out any packets not coming from the IP used when logging in.
· iodine handles setting IP number on interfaces automatically, and up to 8 users can share one server at the same time.

What's New in This Release: [ read full changelog ]

· Fixed client segfault on OS X
· Added check that nameserver lookup was successful
· Fixed ENOTSOCK error on OS X and FreeBSD