pending license change

Vincent Schonau
Thu Mar 17 08:42:33 UTC 2005

Vernon Schryver wrote:
> This week I hope to release a version of the DCC source which will
> include the use of getaddrinfo() for Linux IPv6 support and the
> optional use of a subset of ESMTP by dccifd for use as a Postfix
> before-queue filter among other things.
> After 5 years, I think I've largely exhausted possibilities for the
> DCC as it currently exists.  I have some other ideas, but they depend
> on things that cost money like a feed of the (formerly free) SBL from
> Spamhaus. 

It's high-volume DNSBL access to the Spamhaus SBL that is not free; I 
don't know what sort of features you're thinking of (that are not 
high-volume DNSBL queries); nor if you've asked Spamhaus about free 
access. My experience from my dealings with Spamhaus is that they are 
quite willing to work with others. Spamhaus is not trying to build a 
business, as MAPS was (and is, I guess). I can't think of many uses of 
that data that can't be generalised to make them usable with other 
(DNSBL) services, that are free.

> So I'm close to signing an agreement with Commtouch that
> includes support for those ideas.  It requires changes to the license
> for versions of the DCC source after this week's.  The changed license
> is intended to leave the DCC as free as it was before except
>    "... any entity which sells anti-spam solutions to others, or
>    provides an anti-spam solution as part of a security solution
>    sold to other entities, or to a private network which employs
>    DCC or uses data provided by operation of DCC but does not provide
>    corresponding data to other users."

Is this intended to mean DCC servers or deployments which do not connect 
to the global DCC network, such as it is, but instead only to eachother 
(or themselves)?

> That exception/restriction does not apply to ISPs and others who filter
> their own spam with their own DCC installations. is part of the global DCC network and a public DCC server 
but serves only me and a few people close to me as an anti-spam solution 
(leaving out the spamtraps that feed into it). The DCC servers at XS4ALL 
which I manage are part of the 'anti-spam solution' that XS4ALL offers 
which is available to all customers that use e-mail. They connect to the 
global DCC network but do not 'provide corresponding data' to other 
users in any other way. Both cases seem to be covered by the intended 
restriction and then explicitly excepted from it. That would reduce the 
group of users covered by the restriction to commercial anti-spam 
providers that are not ISPs. I see some names in the list of servers in 
the global DCC network that would appear to be affected by this change.

I'm not sure if I fully understand the intended restriction or the 

> Future versions of
> DCC (e.g. fixes to bugs I've missed in the Postfix stuff) remain as
> free as before to them.

Thank you for that (and for the DCC as it is today).

> (The new ideas can't be free because they are
> likely to cost money in fees to third parties).  The agreement includes
> a promise to me to not sue or try to collect royalties Patent 6,330,590
> from organizations covered by the new, restricted license.

This seems to mean that anyone intending to develop something based on 
the existing DCC code had better be prepared to defend themselves 
against such claims or be willing to pay royalties to Commtouch. It may 
also mean that anyone using the existing DCC code may have to do that. I 
hope that is not the case.

That patent was discussed here last october:
including the following advice to the patent holder:

> The DCC works better as more systems particpate.  Anything that reduces
> participation in the global DCC network might reduce the value of the
> patent.

I hope Commtouch understands that.

> I guess you might say I'm selling out for a pittance to one of the
> commercial anti-spam vendors, but I hope in a way that does not affect
> anyone except other commercial anti-spam vendors, and in a way that
> will help reduce spam overall.  I tell myself there are far worse
> possibilities.

There definitely are, although some who value 'Free Software' or 'Open 
Source[tm]' above anything else will probably disagree.

If the world was as dependant on commercial anti-spam providers to 
reduce spam overall as it is on commercial anti-virus providers to 
reduce the effects of malware I would be worried. That's not the case 
for either effective spamfiltering (many open and free and unencumbered 
solutions are and will continue to be available), and it isn't the case 
for efforts to reduce the amount of spam sent (which do not involve 
spamfilters except indirectly as one way to pressure spammers and 



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