More on remailers.

[Steve Schear]

At 06:01 PM 12/21/2001 -0500, dmolnar wrote:
>On Fri, 21 Dec 2001, Len Sassaman wrote:
>
>
> > Publishing failure notifications with sender-provided keys, as Steve
> > Schear suggests, seems likely to have large implementation and usage
> > hurdles. (A separate user's public key for each remailer in the chain
> > would have to be sent along with each message, and managing this would
> > become quite difficult for the user.)
>
>One way around this management issue might be to use a public-key
>cryptosystem which supports "key blinding." (Note - A Google search
>reveals that this term seems to be used in other places as well, and it
>looks like the usage there is not quite consistent with the way it is used
>in this message. Caveat lector.)

An alternative method, discussed privately with another CP list member, 
would have the sender could provide a response-inbound message appropriate 
for each remailer in the chain and imbed this with the outbound message 
(maybe in the header). This imbedded message would be a concentrically 
wrapped and encrypted message just like the sender's outbound message, but 
constructed so it would backward chain to the originator.  Might not even 
be to the same address as the sender's to obfuscate the linkage. Similar to 
reply block.

My preference is using a Web server interface in the remailer to allow the 
originator's client to automatically check the progress of their message.

steve