Subject: Re: Ipsec NAT traversal: some legal work to do
To: None <>
From: Christos Zoulas <>
List: netbsd-users
Date: 10/01/2004 17:23:19
In article <>,
Emmanuel Dreyfus <> wrote:
>IPsec NAT traversal (NAT-T for short) is needed when any end of an IPsec
>communication are behind a network address translator. This is extremlely
>useful when using IPsec for remote user access VPN. NetBSD does not 
>implement it.
>I wrote the code, and it works, but it cannot be included in the tree because
>of a legal problem: it seems MS holds a US patent on it. 
>I don't live in a country where software patents are legal, so I don't care, 
>I will use my code without contributing it to the tree. If you would like
>to see NAT-T committed in NetBSD, then it is time to offer your help.
>We need someone that will read carefully the patent description and check
>if that covers what we do. If it does, then the position of other free OS
>whould be checked: Linux integrated it, what was their legal conclusions? (for
>instance, maybe they found prior art). What did OpenBSD did? 
>The last option can be to request a license from Microsoft, the problem there
>will be to find the right person to speak with.

Look at: