spf-discuss
[Top] [All Lists]

Re: [spf-discuss] Yet another attempt to fix forwarding

2008-02-01 18:25:02
At 12:16 PM 2/1/2008 +0100, Alessandro Vesely wrote:
David MacQuigg wrote:

Requirements for Solution to Forwarding Problems
1) Use IP-based authentication (signatures are a separate topic)

In this fix-forwarding tentative solution (hereafter FF) we might use 
user/password authentication, where "user" is the above FQDN and "passwords" 
are generated by the granting host.

Good point.  As a Recipient, my own forwarding arrangements involve only 
password authentication.  My Forwarders have no direct relationship with my 
MDA.  To make changes at any of these Agents, I sign in with a password.

I should have said something like - if authentication is necessary, use 
something simple.  I deleted this requirement from the list, since the valid 
parts are implicit in the other requirements.  What I was really trying to say 
was let's not get involved in discussing solutions far outside the scope of 
this group, as the details of signature-based methods would certainly be.

FF requires a database with <forwarder, envelope recipient> tuples. Obviously, 
the Recipient already has an envelope-recipient database: It will be 
multiplied by a number of Forwarders who have the corresponding forwarding 
configuration. On average, the resulting figure could match the number of 
forwarding recipes that a Forwarder already stores for the envelope recipients 
in its own database. However, that may be a problem in some cases.

Even if it represents an additional cost, that data is needed for 
privacy-compliant forwarding - the problem I state below and that is missing 
from http://open-mail.org/Forwarding.html

Problem P - It is a mess to keep track of forwarding chains, let alone 
updating any of those nodes.

Maybe we could re-state this more clearly as: Problem P - Recipients have 
difficulty keeping track of and updating their forwarding arrangements.  I 
added that to our Statement of Forwarding Problems at the link above, with a 
note "still needing discussion".

-- Dave



-------------------------------------------
Sender Policy Framework: http://www.openspf.org
Archives: http://v2.listbox.com/member/archive/735/=now
RSS Feed: http://v2.listbox.com/member/archive/rss/735/
Modify Your Subscription: 
http://v2.listbox.com/member/?member_id=2183229&id_secret=92935678-33ccfd
Powered by Listbox: http://www.listbox.com