🚀 go-pugleaf

In <1992Aug18.221506.13535@Princeton.EDU> dla@raven (Don Alvarez) writes:

>In article <9208182108.AA09132@news.cis.ohio-state.edu> Marc.Ringuette@daisy.learning.cs.cmu.edu writes:
>>
>>The basic technique I propose in order to achieve this is a two-stage news
>>distribution process, where first the news is distributed to the entire set
>>of receiving machines, then signatures are collected from all receivers and
>>distributed in the same way as a regular news article.  
>>
>>Machines must register themselves by posting to the newsgroup, and must agree
>>to respond to signature requests within a reasonable window, or they will be
>>removed from the set of participating hosts.  
>>
>>What do you think?  See any gaping holes?  Want to flesh it out and 
>>give it a try?
>>
>>    --Marc Ringuette, mnr@cs.cmu.edu

>Gaping holes?  *YES*

>There is no central authentication server, so every subscriber must be
>able to determine authentication themselves.  That means every
>subscriber needs a list of the names of all of the other subscribers.

>Any subscriber can fraudulently "authenticate" any posting simply by
>greping through the list of subscribers and announcing "subscriber foo
>received article 754", "subscriber bar received article 754", etc.

Actually, if the "signatures" are cryptographic, there may be a solution to that.
You have to define "subscribers" as key-holders rather than as machines,
but it seems somewhat reasonable.

...

>Worse, there is no way for any machine even to know that it has a complete
>or accurate list of subscribers because there is no way to distribute
>such a list in a trusted manner.

That's true.

>Providing a centralized server for doing the authentication wouldn't
>help, because there is no way for it to know who is sending the
>subscription messages or who is sending the receipt messages.  There
>would also be no way for the individual subscribers to know who sent
>the "article 754 authenticated" message.

That's not correct.  If you believe public key signature systems can be
secure, then a message can be posted which has the effect that "someone
with key K1 posted message M1".


--
Arthur L. Rubin: a_rubin@dsg4.dse.beckman.com (work) Beckman Instruments/Brea
216-5888@mcimail.com 70707.453@compuserve.com arthur@pnet01.cts.com (personal)
My opinions are my own, and do not represent those of my employer.
My interaction with our news system is unstable; if you want to be sure I see a post, mail it.