Subject: [Asrg] My take on e-postage

From: Jonathan Morton <[email-masked]>
Date: Sun, 25 Apr 2004 07:55:13 +0100

First things first.  The resource being consumed/abused is the 
recipient's inbox.  Therefore we need to make any charge a condition of 
entry into a participating recipient's inbox.  That means the recipient 
is the one who needs to decide whether a stamp is needed, and whether 
any given stamp is sufficiently valid.

Unilaterally charging a levy at the sending side isn't going to work, 
for a variety of reasons - primarily that the major ISPs will start 
using it as a revenue stream in it's own right, rather than for the 
intended purpose of preventing abuse by it's customers.  Another reason 
is that spammers will set up their own ISPs and backbones to avoid the 
normal stamping routes as much as possible.

In a recipient-driven scheme, senders still have to be able to buy 
stamps, but they will be able to choose their stamp vendor, rather than 
being limited to their ISP.

There's always going to be a zombie-PC problem, to some extent at 
least.  At the moment there are hundreds of thousands of insecure 
Windows machines out there, and they aren't going away.  There is a 
very slight possibility that it might be feasible to economically force 
novice users onto a more secure platform - such as the Mac - but we 
can't rely on that, either.

A problem is that zombies can't merely be used as a relay, they can 
also be used to leech any stamp account the victim uses for their own 
e-mail.  However, the compromised stamp account will quickly either 
become empty or run up a monstrous bill on the victim's credit card 
(the former situation is obviously preferable, and I'd hope that 
consumer stamp accounts were set up that way).  After that, the zombie 
can still spew mail all over the place, but it will be unstamped.  The 
empty account (or huge bill) also serves as a wake-up call to the 
victim, to get their machine cleaned and secured.

The interesting thing is that a stamp can also act as proof of where 
the mail was sent from, and/or who by, because there's a money trail 
(if nothing else) to follow, and each stamp is unique.  This probably 
won't tell you who the spammer is, but it can help for whitelisting, 
forgery detection, and for notifying victims.  And it doesn't require 
the victim's ISP to lift a finger, unless they also happen to be the 
stamp vendor.

The big disadvantage for e-postage is that everyone now has to pay for 
e-mail service.  A service which we presently take for granted as 
incrementally free.

There are alternative schemes which can operate alongside e-postage to 
eliminate the monetary cost for most normal purposes.  A combination of 
a proof-of-work stamp (such as hashcash) and a proof-of-identity 
signature would also serve a useful rate-limiting purpose.  Again, it's 
up to the recipient to decide how strong a guarantee he requires before 
a mail can land in his inbox.  (At the moment, most recipients' 
barriers to entry are exceptionally low, even with today's content 
filters, because there's no practical, universal way to detect forged 
mail.)

The common factor in the above is that the sender can say "I want this 
mail to go through so badly that I will do one or more of the 
following:  prove *I* sent it; pay for a stamp from a trustworthy 
vendor; expend N seconds of CPU time".  The recipient can then look at 
the credentials supplied with the mail, optionally check them against 
stamp vendors' databases (etc.), and decide whether they're good 
enough.

People, please point out what's wrong with the above, specific 
high-level design, not with "e-postage" in the abstract.

--------------------------------------------------------------
from:     Jonathan "Chromatix" Morton
mail:     [email-masked]
website:  http://www.chromatix.uklinux.net/
tagline:  The key to knowledge is not to rely on people to teach you it.

_______________________________________________
Asrg mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/asrg

---

From: der Mouse <[email-masked]>
Date: Sun, 25 Apr 2004 15:05:08 -0400 (EDT)

> high-level design, not with "e-postage" in the abstract.

Have you read the taugh whitepaper?  Some of the points it raises apply
to your sketched design.

In particular, the social resistance to pay-by-unit systems applies,
and the micropayment infrastructure impossibility applies (and even
more so, because you're positing one micropayment infrastructure per
stamp vendor, so you get less economy of scale).

Furthermore, the money paid for stamps goes to the wrong place, ie, not
to the recipients.  (Stamp vendors could in principle pay recipients
who get mail with their stamps.  This involves creation of _another_
micropayment infrastructure per stamp vendor.)

You write that

> stamps, but they will be able to choose their stamp vendor, rather
> than being limited to their ISP.

Except that they have to choose a vendor acceptable to the recipient.
Keeping track of which recipients demand stamps from which vendors will
be another cost which you don't seem to have mentioned.  If there are a
large number of stamp vendors it rapidly becomes almsot intractable.

/~\ The ASCII				der Mouse
\ / Ribbon Campaign
 X  Against HTML	       [email-masked]
/ \ Email!	     7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B

---

From: Barry Shein <[email-masked]>
Date: Sun, 25 Apr 2004 15:18:18 -0400

> any given stamp is sufficiently valid.

Well, I disagree with this 100%, it's just false.

If people could send advertising via paper post for free do you think
the problem is primarily the recipient's? What about the effect it has
on the letter carriers and the postal system in general?

This is another proposal which works forward from spam is free, just
annoying.

It's a terribly naive way to look at resource abuse.

 > intended purpose of preventing abuse by it's customers.  Another reason 

And this is a problem because...?

 > normal stamping routes as much as possible.

But no one will accept their stamps!

Why don't you try setting up your own post office and printing your
own stamps and see how the Royal Post reacts.

 > high-level design, not with "e-postage" in the abstract.

Yeha, who pays for all the overhead in your proposal.

Create an economy, or it's just schoolboy fantasising.

-- 
        -Barry Shein

Software Tool & Die    | [email-masked]           | http://www.TheWorld.com
Purveyors to the Trade | Voice: 617-739-0202        | Login: 617-739-WRLD
The World              | Public Access Internet     | Since 1989     *oo*

---

From: Jonathan Morton <[email-masked]>
Date: Sun, 25 Apr 2004 22:11:16 +0100

> Have you read the taugh whitepaper?  Some of the points it raises apply

No - do you have a link?

> stamp vendor, so you get less economy of scale).

I agree on the social resistance, which is why I proposed the 
proof-of-work stamps (which involve a non-monetary expenditure) to go 
alongside it.  I'm afraid the micropayment argument doesn't hold water, 
because you can always pay for blocks of, say, a thousand stamps at a 
time, and exactly how hard is it to keep track of one counter per 
paying customer?

Incidentally, if you can prove your identity, the recipient can add you 
to a whitelist that says "I don't need a paid stamp from this sender".

> micropayment infrastructure per stamp vendor.)

Good point.  There's a way around this, though - how about the 
recipient's stamp vendor collects a portion of the stamp's value from 
the sender's stamp vendor, and credits it to the recipient's account?  
If accounting is kept at both ends, then actual money would only change 
hands relatively infrequently - in blocks, just like the sender pays 
for the original stamps.  But, this does require some kind of business 
relationship - perhaps via an intermediary to help it scale - between 
the two vendors.

This ignores mailing lists and the like, however.  These are an 
interesting problem, because the sender wants his single mail to be 
seen by all members of the list, which could be thousands of recipients 
- that's a lot of stamps.  For this reason, mailing lists are already 
prime targets of spammers, especially since it's presently quite easy 
to forge entry.

Probably the strongest solution is for the listserv to use the 
proof-of-identity, perhaps combined with a proof-of-work or a paid 
stamp, from the sender - and for the list subscribers to use 
proof-of-identity of the listserv, with a whitelist entry to prevent 
the listserv from having to attach (paid *or* worked) stamps.  But this 
requires upgrading the list software.

Another solution is to use a proof-of-work stamp, made for the 
sender-to-list connection, with a particularly high validity threshold. 
  The recipient can then check that via a whitelist entry on the "To" 
address, without involving the listserv itself.

> large number of stamp vendors it rapidly becomes almsot intractable.

If there are a relatively large number of stamp vendors, then they will 
be differentiated into (roughly) two classes - trustworthy and 
untrustworthy - depending on whether they give out free or subsidised 
accounts to spammers or not.  (Fair enough, some other factors will 
probably come into play as well.)  A relatively large number of vendors 
also helps to open competition.

Recipients can whitelist the trustworthy ones and blacklist the others 
- which is a much easier problem than the present practice of 
blacklisting individual senders.  Senders then only have the task of 
finding a trustworthy stamp vendor, which shouldn't be difficult, and 
they can move away from it if their mails stop getting through.  This 
is made even easier if there are a number of public lists to consult.

Just for the record, I don't believe e-postage is The Solution, in any 
form.  Whether it can sensibly become even part of the solution is open 
to debate.  I'm just trying to get the debate back on track.  :)

---

From: Jonathan Morton <[email-masked]>
Date: Sun, 25 Apr 2004 22:18:08 +0100

> This is another proposal which works forward from spam is free, just

Paper post is charged for on a transportation-costs basis.  If paper 
post were free, then utilisation would indeed go up, increasing it's 
cost, at which point it would no longer be free.  So it stabilises in a 
non-free state, just like it is today.  QED.

By contrast, the transportation costs of e-mail are practically nil.  
Spammers happily paid for phat pipes to send mail through, before 
widespread blacklisting forced them into using zombies.  The cost is, 
and has always been, the recipient's time spent in sifting through the 
mess.  (I count the recipient's ISP in this as well.)

---

From: der Mouse <[email-masked]>
Date: Sun, 25 Apr 2004 17:28:51 -0400 (EDT)

>> Have you read the taugh whitepaper?  Some of the points it raises
>> apply to your sketched design.
> No - do you have a link?

http://www.taugh.com/epostage.pdf - or at least that's where I found it
when I fetched it, and there's still something there now; I haven't
checked that it's the same, but have no reason to think it's not.

> I'm afraid the micropayment argument doesn't hold water, because you
> can always pay for blocks of, say, a thousand stamps at a time, and
> exactly how hard is it to keep track of one counter per paying
> customer?

It's a lot more than that that the stamp vendor needs to keep track of.
The first thing that comes to mind is that recipients need a way to
check that a stamp hasn't already been used - and even if the sender
sends them in order, the recipients won't necessarily check them in
order.

>> Furthermore, the money paid for stamps goes to the wrong place, ie,
>> not to the recipients.  (Stamp vendors could in principle pay
>> recipients who get mail with their stamps.  This involves creation
>> of _another_ micropayment infrastructure per stamp vendor.)

Sounds superficially plausible, but what do you do for fraud
prevention (that is, how can each tell that the other is reporting
honest totals)?  This gets an awful lot of regulatory entities
involved, especially when (say) one of them is in China and the other
is in Nigeria.

> This ignores mailing lists and the like, however.  [...]

Very true.

> Another solution is to use a proof-of-work stamp,

There really is no such thing.  Hashcash is not something that can be
attached to a message; it requires an interactive protocol.  (There may
be some way to do proof-of-work in an open-loop form, but I haven't
seen it yet.)

> Recipients can whitelist the trustworthy [stamp vendors] and
> blacklist the others - which is a much easier problem than the
> present practice of blacklisting individual senders.

For a little while, until spammers start creating throwaway stamp
vendors, the way they create throwaway domains now.

Still, it may be worth trying.  Most of this - on both our parts - is,
fundamentally, speculation, at present.  After all, none of this stops
people who mutually feel like it from continuing to use SMTP the way we
all have been so far.

/~\ The ASCII				der Mouse
\ / Ribbon Campaign

---

From: Jonathan Morton <[email-masked]>
Date: Mon, 26 Apr 2004 00:57:49 +0100

> checked that it's the same, but have no reason to think it's not.

At least some of it's objections seem to hinge on stamps being 
anonymous.  Unlike e-coins, that need not be the case.  As I mention 
below, some problems are more easily solved with identified stamps.

> sends them in order, the recipients won't necessarily check them in

Not necessary, if the stamp cryptographically includes both the sender 
and recipient addresses.  If the recipient doesn't recognise the 
address the stamp was made for delivery to, it's invalid.

> involved, especially when (say) one of them is in China and the other

I don't have a strong solution to that.  However, it should be a simple 
matter to at least list the actual stamps being claimed, and check them 
against stamps issued.

In the event of a dispute - for example, two vendors try to claim the 
same stamp - we start wanting to prove which claiming vendor actually 
has the stamp's addressed recipient as a customer.

One way of doing that, which should be cheap enough to deal with small 
disputes, is to send a special stamp to the recipient and see which 
vendor it comes back from.  Since the revenue from the stamp belongs to 
the recipient, it doesn't matter if he switched vendors in the 
meantime.  It also doesn't particularly matter if the test stamp never 
comes back.

For wider disputes, when measurable amounts of money get involved, you 
start bringing humans in to negotiate.  At some point, you might need 
to downgrade disputing vendors' reputation, or even start legal 
proceedings.  That last, however, is way beyond any reasonable 
technical measures, and indicates (alleged) fraud on the order of 
hundreds of thousands of stamps.

> be some way to do proof-of-work in an open-loop form, but I haven't

Why is this?  Is it because the validity threshold of the recipient 
isn't a priori known to the sender?  If so, then a variation on the 
usual "delivery failed" mechanism (insufficient hashcash for delivery, 
please send 30 bits) should handle it.  If for some other reason, 
please expand.

> vendors, the way they create throwaway domains now.

Which is why I said whitelists as well as blacklists.  It does mean 
there will be some barrier to entry for new stamp vendors, but I don't 
know if that will be a serious problem.

> people who mutually feel like it from continuing to use SMTP the way we

Naturally.  This is also why the proprietary systems being proposed by 
certain large corporations may not succeed, however much money is 
behind them.

---

From: der Mouse <[email-masked]>
Date: Sun, 25 Apr 2004 20:18:49 -0400 (EDT)

>> It's a lot more than that that the stamp vendor needs to keep track
>> of.  The first thing that comes to mind is that recipients need a
>> way to check that a stamp hasn't already been used
> Not necessary, if the stamp cryptographically includes both the
> sender and recipient addresses.

Then the recipient needs a way to check the crypto signature - and even
then, you have to figure out a way that stamps can't get reused with
forged sender addresses.  (That is, X sends mail to Y, with a valid
stamp <X,Y>.  Spammer gets hold of a copy (through any of many possible
means) and sends mail with that stamp, to Y, forging X's address as the
sender.)

>> There really is no such thing.  Hashcash is not something that can
>> be attached to a message; it requires an interactive protocol.
>> (There may be some way to do proof-of-work in an open-loop form, but
>> I haven't seen it yet.)
> Why is this?

Why?  Simply because all the hashcash protocols I've seen outlined, or
that I've thought of, involve some kind of challenge by the recipient
which must be answered by the "payer".  A simple example might be "find
a data blob whose SHA-1 hash has these 20 bits set to these values".

As I said, I don't know whether this is an inherent property of
hashcash (by which I really mean "proof-of-work", even though,
strictly, hashcash is but one form of p-o-w) or whether it's just an
artifact of the hashcash schemes I am aware of.  But until someone
shows me one which doesn't have that property, I have to operate under
the assumption that no such thing exists.

/~\ The ASCII				der Mouse
\ / Ribbon Campaign

---

From: Jonathan Morton <[email-masked]>
Date: Mon, 26 Apr 2004 02:53:53 +0100

> means) and sends mail with that stamp, to Y, forging X's address as the

But the recipient Y will be able to tell if he's seen the same stamp 
twice.  That's trivial to deal with, especially since most modern MUAs 
(well, Eudora and Apple Mail, anyway) index their mail archive already 
by default.

As for verifying crypto signatures, the public key from the vendor is 
needed for that, since the vendor issued the stamp.  This is, broadly 
speaking, a one-time operation, which happens after the sender vendor's 
trustworthiness has been looked up.  It's also an operation that could 
potentially be offloaded on the recipient's vendor, since the recipient 
is probably going to send the stamp there for reimbursement anyway.

> the assumption that no such thing exists.

Ah, I see what you're missing.  What you need is more like "find a data 
blob Y, which is different from this challenge X, where both X and Y 
have the same first N bits in their SHA-1 hash".  The challenge can 
then be arranged so that it contains various pieces of information 
about the mail itself, such as the sender, recipient, creation date and 
time, and possibly part of the content and/or some of the other header 
fields.

This way, the sender and the recipient can both figure out what the 
challenge should be (except for the number of bits, but a sensible 
default can be assumed), and the sender can then, with reasonable 
confidence about validity, attach the hashcash stamp to the mail.  If 
the sender has previously conversed with this recipient, it will also 
have a priori knowledge of N, improving efficiency.

---

From: Seth Breidbart <[email-masked]>
Date: Sun, 25 Apr 2004 22:50:21 -0400 (EDT)

> a data blob whose SHA-1 hash has these 20 bits set to these values".

Simple attempt (which probably won't work, but would take me a few
hours to figure out why):  "The message, including the timestamp
(which must be accurate to 10 seconds and only one is accepted per 10
seconds) and including From and Envelope-To (same as To) must have the
first 20 bits of its MD5 equal to 10101010101010101010; you may insert
an X-HashCash-Munger: header to make it work"

You can't do the work once for many recipients because the recipient
is included in the hash; and you can't re-use it because of the
timestamp.

Seth

---

From: der Mouse <[email-masked]>
Date: Mon, 26 Apr 2004 00:12:25 -0400 (EDT)

>> Why?  Simply because all the hashcash protocols I've seen outlined,
>> or that I've thought of, involve some kind of challenge by the
>> recipient which must be answered by the "payer".  A simple example
>> might be "find a data blob whose SHA-1 hash has these 20 bits set to
>> these values".
> seconds) and including From and Envelope-To (same as To) must have
> the first 20 bits of its MD5 equal to 10101010101010101010;

> is included in the hash;

Right.

> and you can't re-use it because of the timestamp.

Not quite that simple.

If the timestamp must match the time of the SMTP handoff, then you have
to recompute the hashcash for every retry (and are vulnerable to
unusually slow SMTP connections or recipient clocks set wrong); if the
timestamp need not match the time of the SMTP handoff, you are
vulnerable to backdated reuse.

You may be on to something here, though.  How about:

	The MD5 of the envelope-from, the envelope-to, the From:, To:,
	Message-Id:, and X-HashCash: headers, in that order,
	concatenated with the entire message body, must begin with
	however many 0 bits the recipient requires.

I think that addresses the issue.  Thank you.  (Replay isn't, I think,
much of an issue, when you can replay only whole messages including the
envelope.)

Of course, it still suffers from the usual problems endemic to all
hashcash, notably the very wide variety in CPU speeds out there.
J. Random Hacker in Outer Slobbovia running on a half-lung salvaged
68020 will be utterly blocked by hashcash values high enough to be even
noticed by Evil Q. Spammer's late-model 8-CPU 18GHz Hexium.

/~\ The ASCII				der Mouse
\ / Ribbon Campaign

---

From: Jonathan Morton <[email-masked]>
Date: Mon, 26 Apr 2004 07:54:08 +0100

> noticed by Evil Q. Spammer's late-model 8-CPU 18GHz Hexium.

Some numbers, using hashcash 0.27 (compiled with optimisation for each 
machine):

My 16MHz 68030 (an old Mac pulled from a skip) can do 1000 hashes a 
second - it'll take 15-20 minutes on average to do a 20-bit collision.  
For the impoverished people that must rely on such a machine, this is 
vaguely acceptable.  They can always go outside and do a bit of 
gardening while they wait.

My 200MHz Pentium-MMX can do 84000 hashes a second, reducing the time 
for a 20-bit collision to 12 seconds - a much more acceptable figure.  
The vast majority of Internet users in the Western world have a machine 
at least this fast.  Indeed any Pentium-class CPU would appear to be 
able to produce a 20-bit collision in under a minute (on average).

My 1600MHz Athlon-XP can do 575000 hashes a second - enough to reduce 
the time for a 20-bit collision to 2 seconds.  Most enthusiasts and 
power users have a machine about this size, which reduces a 20-bit 
hashcash to near invisibility for normal levels of e-mail.

I estimate that the fastest current-generation CPUs can do a 20-bit 
collision in about 1 second.  Assuming spammers can build 4-way boxes 
out of these, how many boxes will they need to fill a T1 to capacity, 
the way they used to?  Assuming a 5KB spam size, about 7500 of them.  
Is this economically feasible for the spammer?  You tell me.

So, assuming the spammer is limited to conventional CPUs and that 
hashcash is widely used, he is now rate-limited to 1 spam per second 
per CPU for machines he builds himself, and perhaps 1 spam per 2-5 
seconds per zombie he controls.  This is a VAST improvement on the 
current situation.

On the other hand, in an earlier discussion on this subject, I pointed 
out that dedicated hardware can be built to accelerate hashcash 
generation.  Someone else replied that if the spammers can do it, so 
can Taiwan, and cheaper.  If everyone has access to a SHA-1 coprocessor 
and an e-mail program that supports it, the playing field becomes more 
level, not less.

However, there's a flaw in that argument too, because coprocessors 
cheap enough for Aunt Tillie to buy one without thinking too hard about 
it, are also cheap enough for the spammers to buy in hundreds, together 
with a huge batch of USB hubs to plug them into a mere handful of 
servers.  But that still means the spammers can "only" send hundreds of 
times as much mail as Aunt Tillie, which is still a vast improvement on 
the status quo.

---

From: Eric Rescorla <[email-masked]>
Date: Mon, 26 Apr 2004 06:12:42 -0700

> noticed by Evil Q. Spammer's late-model 8-CPU 18GHz Hexium.

One response to this has been to try to design functions that are
less dependent on processing power and more dependent on stuff
that's less variable. 

See, e.g.,

http://citeseer.ist.psu.edu/context/2125750/0
http://citeseer.ist.psu.edu/554568.html

That said, I seem to remember hearing that there have been
problems with these functions, though I don't track the
field that carefully...

-Ekr

---

From: Jonathan Morton <[email-masked]>
Date: Mon, 26 Apr 2004 14:41:08 +0100

> problems with these functions, though I don't track the

The main one I remember (offhand) is something using memory bandwidth 
rather than core.  The problem with that is anything with a large 
enough working set to swamp the 2MB and 4MB on-die caches that are now 
appearing, will simply not run on my Mac IIcx with only 8MB *total* 
RAM.

And the spammers can always splurge for a big IBM POWER5 workstation 
with 8MB on-module L2 cache (4 dies per module, 2MB per die) and insane 
amounts of L3 cache.

---

From: John Levine <[email-masked]>
Date: 26 Apr 2004 14:55:39 -0000

>  Assuming spammers can build 4-way boxes out of these, how many
> boxes will they need to fill a T1 to capacity, the way they used to?
> Assuming a 5KB spam size, about 7500 of them.  Is this economically
> feasible for the spammer?  You tell me.

Of course it is.  They infect 10,000 new zombie PCs every day.

Regards,
John Levine, [email-masked], Taughannock Networks, Trumansburg NY
http://www.taugh.com

---

From: "Chris Lewis" <[email-masked]>
Date: Mon, 26 Apr 2004 12:37:47 -0400

> Of course it is.  They infect 10,000 new zombie PCs every day.

Multiply that by 6. We're seeing 65,000 - 70,000 zombie detections per 
day, and the daily detection count is still trending upwards.

80% of spam detected by this method (it's catching approximately 65-70% 
of all of our spam) is coming from detections less than 4 days old.  90% 
< 6 days old.  95% < 12 days old.

Are we having fun yet?

---

From: Daniel Feenberg <[email-masked]>
Date: Mon, 26 Apr 2004 14:17:39 -0400 (EDT)

> < 6 days old.  95% < 12 days old.

Can you tell us the number of hosts in each category? And how long hosts
remain infected? That would give us an idea of the gross flows into and
out of infected status.

If spam is proportionate to hosts, then the above figures suggest that 75%
of hosts are corrected within 4-6 days. My reasoning is that only 10x more
hosts are in the 6 day window than in the 4 day window. So if there are
80x infected hosts in 4 days, that is 20x hosts/day. But in 6 days there
are only 90x total infected hosts, or 5x hosts/day for the 2 additional
days rather than the expected (steady state) 20x hosts. That suggests that
15x hosts were cleaned up. This would be clear if we knew the number of
hosts, so that I didn't need the mystery factor x =spams/(hosts*100)

Daniel Feenberg

---

From: "Chris Lewis" <[email-masked]>
Date: Mon, 26 Apr 2004 14:33:14 -0400

> remain infected? That would give us an idea of the gross flows into and

Here's a table:

Age (days)   IP Count/cum%  Hit Count/cum%
          0      67974/ 5.0     174862/25.4
          1      65816/ 9.8     184589/52.1
          2      54233/13.8     118338/69.3
          3      48207/17.4      50991/76.7
          4      38517/20.2      45567/83.3
          5      42021/23.3      42143/89.4
          6      55652/27.4      26002/93.2
          7      57634/31.6       3889/93.7
          8      50108/35.3       2445/94.1
          9      45304/38.6       1551/94.3
         10      54740/42.6       3264/94.8
         11      60550/47.1       3612/95.3
         12      43338/50.3       2883/95.7
         13      42773/53.4       7164/96.8
         14      47288/56.9        942/96.9
         15      44260/60.1        524/97.0
         16      48189/63.7       1087/97.1
         17      43812/66.9       1147/97.3
         18      39178/69.8        864/97.4
         19      39474/72.7        611/97.5
         20      38916/75.5       1320/97.7
         21      40344/78.5        894/97.8
         22      37221/81.2       3122/98.3
         23      28497/83.3        907/98.4
         24      32483/85.7       1000/98.6
         25      38186/88.5       4719/99.3
         26      42249/91.6       1393/99.5
         27      41198/94.7       1816/99.7
         28      39267/97.6       1487/99.9
         29      33023/100.0       396/100.0
         30        261/100.0         0/100.0
     Totals    1360713/ 100     689529/ 100

We expire after 30 days.

> of hosts are corrected within 4-6 days.

It isn't proportionate to hosts.

> My reasoning is that only 10x more

I think you'll find that the rapid dropoff isn't necessarily due to 
system cleanups, but rather to spammers using the newest ones possible 
to avoid blacklisting.

---

From: Barry Shein <[email-masked]>
Date: Mon, 26 Apr 2004 17:03:42 -0400

> By contrast, the transportation costs of e-mail are practically nil.  

 No they're not.

  Yes they are.

 No they're not.

  Yes they are.

 No they're not...

  Yes they are.

I can see we are now in a context-free loop.

As founder and CEO of an ISP for these past ~15 years I actually
provide e-mail systems to the general public and do the budgets etc so
have some actual, current, knowledge about the costs.

And you...?

 > mess.  (I count the recipient's ISP in this as well.)

Spammers use zombies for two major reasons:

1. IP mobility - to avoid blacklisting as you say.

2. Free resources - the economics of spamming is such that they must
steal resources, they could never pay for what they consume, their
service just isn't valuable enough which is why it tends to revolve
around cheesy come-ons for mostly phony penis enlargement pills and
similar.

Point 2 is in direct contradiction to what you asserted, that they
"happily paid for phat pipes", can you tell me what you base that
assertion on?

The important point is that what spammers sell is CRIME.

They don't sell advertising, any more than a guy who sells stolen
watches out of the back of his car is selling watches.

You might end up with a watch, but the value of his service is CRIME,
being able to offer you one cheaper than one might reasonably expect
because it's stolen, his costs are nearly zero.

The same can be said of spammers.

They employ zombies and open relays etc because that is the crime they
are selling.

If the spammer had to provide the service legally he'd have to charge
many times what he charges, probably some astronomical sum to slam
100M mailboxes w/ a penis enlargement ad, just for a comparison paper
email to 100M in the US would cost around $2M in postage alone.

I'll wildly guess that for a legitimate advertiser $100,000 would be a
very reasonable charge for sending email to 100M mailboxes, assuming
such a thing existed. That's around 1/10th cent per piece.

What do you imagine a spammer charges to send 100M pieces? $100?
Probably around that.

Now, tell me what your brain says to you when someone offers you a
brand new Rolex in the box for $100? Howsabout $10? Howsabout 10c?

Anyhow, just like the watch, the customer might ultimately get some
advertising (and that watch *might* be a rolex for $100), but the
actual service is crime.

Just like you could steal a watch for yourself, you could spam for
yourself, but there is a certain wisdom in paying a criminal to do it
for you.

Thus, all spammers are criminals.

                          Quod Erat Demonstrandum.

-- 
        -Barry Shein

---

From: Jonathan Morton <[email-masked]>
Date: Mon, 26 Apr 2004 22:48:38 +0100

> have some actual, current, knowledge about the costs.

I have a calculator and a rough idea of what a T1 line costs, plus I'm 
making some assumptions which are probably valid in the US and many 
other Western countries.

As an ISP, you're part of the recipient's end of the system, not the 
transport part.  If you were a backbone, your experience on transport 
costs would be more useful for this particular argument.

> "happily paid for phat pipes", can you tell me what you base that

I've read a couple of media interviews with spammers, back when they 
still did use their own T1 lines and servers.  The journalist could see 
all the equipment stacked up and working away.

> What do you imagine a spammer charges to send 100M pieces? $100?

Given that spammers typically work from an illegally collected list of 
addresses, that's actually quite a reasonable price.  If each spam is 
5K, 100M of them can be sent over a T1 in about an hour or two, 
ignoring bounces and retries, and assuming he's got a fast enough 
server.  He only needs four or five $100 jobs a month to break even on 
the T1 rental.  Ten, and he can live comfortably off the proceeds.

So clearly the bandwidth cost of e-mail is negligible, somewhere around 
the microcent level.  The costs to the recipient - and his ISP - are 
not.  That was my entire point.

The reason why the legit advertiser could charge so much per impression 
is that their address list must be collected and maintained far more 
carefully.  They might also get a better response rate, because they 
can target the appropriate markets and avoid causing offence.

---

From: GertJan Hagenaars <[email-masked]>
Date: Mon, 26 Apr 2004 18:03:23 -0400

Apparently, der Mouse wrote:
% >> It's a lot more than that that the stamp vendor needs to keep track
% >> of.  The first thing that comes to mind is that recipients need a
% >> way to check that a stamp hasn't already been used
% > Not necessary, if the stamp cryptographically includes both the
% > sender and recipient addresses.
% 
% Then the recipient needs a way to check the crypto signature - and even
% then, you have to figure out a way that stamps can't get reused with
% forged sender addresses.  (That is, X sends mail to Y, with a valid
% stamp <X,Y>.  Spammer gets hold of a copy (through any of many possible
% means) and sends mail with that stamp, to Y, forging X's address as the
% sender.)

Keep a cache of "seen stamps" for 10 days, refuse delivery of duplicate
stamps, and make sure that stamps expire after a week or so.

I do that now with message-IDs to remove duplicate messages to my inbox.

However, the real trick is that it becomes much harder to scale this
even if stamps are readily available.  Instead of just using a single
"to", now the spammer needs to keep track of both "from" and "to".  And
because of this, it becomes much easier to filter out specific spam.

E.g. if I intend to receive email from you, I would have a specific
filter that says that I will need to see a received line with
sparkle.rodents in it.  Or that I need to see the phrase "Ribbon
Campaign" in the body of the email.

Now we're getting into the area where it is no longer possible for a
spammer to break into this scheme without a lot more knowledge of how my
filters are set up.

<pre>
% /~\ The ASCII				der Mouse
% \ / Ribbon Campaign
%  X  Against HTML	       [email-masked]
% / \ Email!	     7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B
</pre>

CHeers,
GertJan.

-- 
+++++++++++++ -------- +++++ --- ++ - +0+ + ++ +++ +++++ ++++++++ +++++++++++++
sed '/^[when][coders]/!d         G.J.W. Hagenaars -- gj at hagenaars dot com
    /^...[discover].$/d          Remembering Mike Carty 1968-1994
   /^..[real].[code]$/!d         UltrixIrixAIXHPUXSunOSLinuxBSD, nothing but nix
' /usr/dict/words                I'm Dutch, what's _your_ excuse?

---

From: Jonathan Morton <[email-masked]>
Date: Tue, 27 Apr 2004 00:12:53 +0100

>>> 80% of spam detected by this method (it's catching approximately 
>>> 65-70% of all of our spam) is coming from detections less than 4 
>>> days old.  90% < 6 days old.  95% < 12 days old.
>>

<snip>

I don't get it.  Why is the hit count for some days so much lower than 
the host count?

Anyway, assuming your figures are correct, that indicates that 2/3rds 
of the hosts are rolling around to the beginning of the list again, 
because they're being detected as new immediately after being expired.  
That in turn seems to suggest 25k new zombies per day, rather than 70k. 
  The total zombie pool is probably a more reliable figure, which I'll 
round up to 1500k.

Assuming they're maximally used for sending spam for about 4 days on 
average, that's a sending pool of about 100k machines.  If each has an 
average 128Kbit DSL uplink, that's equivalent to about 8000 T1s, each 
at 30k spams per second, totalling 240M spams per second.  Rather a lot 
of bandwidth to draw upon, isn't it?

Now let's assume that hashcash is widely deployed, but that the 
spammers have now set up a reasonably efficient P2P network between the 
zombies, allowing even the blacklisted ones to generate stamps for the 
others.  Most zombies won't be screaming top-of-the-line boxes, rather 
there'll be a lot of 1-CPU Celerons and the like, so say 4 seconds per 
20-bit collision on average.

With 1.5M of them churning away, that's 375k spams a second - a massive 
3 orders of magnitude reduction compared to 240M, even if it is still 
enough to saturate 12 T1s.

So, OK, this is definitely going to turn off the non-hardcore spammers. 
  Those that are left will be the ones to send the law after.  Theft of 
service and computer intrusion on this kind of scale is a crime, no 
matter whether the actual spam is.

---

From: Yakov Shafranovich <[email-masked]>
Date: Mon, 26 Apr 2004 19:50:12 -0400

> matter whether the actual spam is.

What you also have to factor here is how much money will be saved in 
order to produce this reduction versus the costs required to convert 
everybody to hashcash.

Yakov
-------
Yakov Shafranovich / asrg <at> shaftek.org
SolidMatrix Technologies, Inc. / research <at> solidmatrix.com
"And this too shall come to pass"
-------

---

From: Daniel Feenberg <[email-masked]>
Date: Mon, 26 Apr 2004 20:41:19 -0400 (EDT)

> Age (days)   IP Count/cum%  Hit Count/cum%

Comparing IP addresses only, it looks like that dropoff from day zero to
day 9 (10 days) is about 1% per day. That is, 5% of hosts in one day, but
38.6% in 10 days.  1% cure rate per day is much more in accord with my
expectations, but still better than never, which is what I feared.

Daniel Feenberg

---

From: der Mouse <[email-masked]>
Date: Tue, 27 Apr 2004 00:39:51 -0400 (EDT)

> [(No they're not.\nYes they are.\n)*]

> provide e-mail systems to the general public and do the budgets etc
> so have some actual, current, knowledge about the costs.

So, don't be coy, tell us: what _does_ it cost to transport an email -
let's be generous and say a hundred-kilobyte email - from point A to
point B?

I'm paying CAD 30/month for any amount of data transfer up to something
like 4GB.  Of course, that pays for many other things too (like the use
of endpoint equipment), but let's assume that is purely my share of the
transport of up to 4GB of data.

At that rate, transporting that hundred kilobytes costs a smidgen under
CAD 0.0007153 - less than three-quarters of a tenth of a cent.  A more
reasonable ten-kilobyte email - this one is maybe 3.5K before addition
of all the Received: goop - would cost about a tenth that, or some
seven millicents.

Compared to all the other costs, notably the human costs, and
especially considering that that's a gross overestimate because my
$30/mo is paying for a number of things other than pure data transport,
I think it's fair to call this "practically nil".

> 2. Free resources - [...]

What reason do you have to think you know why spammers use zombies?

> "happily paid for phat pipes", can you tell me what you base that

A number of past spamhauser _did_ pay for fairly fat pipes - or at
least I've seen it reported thus, and not contradicted; I've not
personally seen invoices or any such.  Any spamhaus that does this,
though, will rapidly find their IP space blocked (and, depending their
upstream, sometimes yanked); I've always assumed that this is the major
motivation behind spammer use of zombie armies.  Indeed, the whole
basis for differential routing abuse is "fat pipe out, thin pipe in".

>                           Quod Erat Demonstrandum.

You have not demonstrated this.  For all your pretty arguments, and for
all that I agree with most of them, you have not shown any point of
criminal law that they are violating.  (I suspect there are such, but
your arguments haven't shown so.)

/~\ The ASCII				der Mouse
\ / Ribbon Campaign

---

From: "Chris Lewis" <[email-masked]>
Date: Tue, 27 Apr 2004 10:45:06 -0400

> I don't get it.  Why is the hit count for some days so much lower than 

The detector is running on a multitude of dmoains with vastly higher 
flows in total, whereas the hit count above is on our own production 
mail service.

> Anyway, assuming your figures are correct, that indicates that 2/3rds of 
> the hosts are rolling around to the beginning of the list again, because 
> they're being detected as new immediately after being expired.  That in 
> turn seems to suggest 25k new zombies per day, rather than 70k.

Not quite - there's some information you're missing.  Minimum 
redetection interval is 48 hours, yet this is on last detection.  On the 
other hand, the numbers for previous days isn't going down by much. 
That first number (70K) is continuously rising.  A month or two ago it 
was around 15-20K, a few months before that, it was 5kish.  The 
redetection interval hasn't changed.

> The 
> total zombie pool is probably a more reliable figure, which I'll round 
> up to 1500k.

Dynamic IP detections (this thing makes no distinction) would tend to 
push it back down.

When the expiration interval was four months, the total was around 
2200K. The reduction of 4mos -> 1mos resulted in an immediate 
2200K->1000k reduction, but only lost 3% of the detections.

---

From: Barry Shein <[email-masked]>
Date: Tue, 27 Apr 2004 17:56:23 -0400

>let's be generous and say a hundred-kilobyte email - from point A to

Why would you only want to include transportation/bandwidth costs?

This reminds me of people who'd call us and demand that a web site
should only cost what the disk space it takes up costs, pennies, paid
once.

Granted I'd separate, e.g., human costs.

But one reason for that is because we'll see something like 100K spams
for every one that ends up in front of a human (e.g., unknown users
via dictionary searches.)

For those there's zero human cost in terms of someone having to read
and delete those, but the cost in equipment etc bear a barrage like
that seems reasonable (remember my comment about 1,000+ systems
spewing the same spam simultaneously not being unusual?)

Anyhow, what's your point, I seem to have completely lost that, that
movie theater tickets should be about 1c because that's a good
approximation of the wear and tear on the seat and they were going to
show the movie anyhow so why leave a seat empty a penny is better than
nothing?

>your arguments haven't shown so.)

Is your point that you doubt that, e.g., hijacking PCs via use of
viruses/trojans and using them for personal gain (spamming) isn't
criminal?

I suppose you should be free to hold that view or even demand that
someone convince you otherwise but somehow my instincts tell me you're
just being argumentative and grasping for straws here.

My point is that spammers' economics are such that they could not be
the problem they are without mass unauthorized utilization of others'
resources, such as the current favorite mode of using hijacked zombie
PCs by the thousands.

Is that carefully worded enough for your tastes while still making the
point w/o attempting to win a case against Johnnie Cochran? Or should
I throw in some allegedly's also?

Sheesh.

Haven't we gone waaaaaaaaaaay beyond trying to tackle this problem and
are now neck deep in trying to nitpick each other to death?

Ya know who's gonna win that one doncha? THE SPAMMERS!!!

-- 
        -Barry Shein

---

From: der Mouse <[email-masked]>
Date: Tue, 27 Apr 2004 18:32:33 -0400 (EDT)

>> So, don't be coy, tell us: what _does_ it cost to transport an email
>> - let's be generous and say a hundred-kilobyte email - from point A
>> to point B?

Because we were discussing the transportation costs of email as
compared to its other costs.  The quote from chromi in the message of
yours that I replied to is "By contrast, the transportation costs of
e-mail are practically nil.".

> Anyhow, what's your point, I seem to have completely lost that,

That the transportation costs of email are practically nil, as compared
to its other costs (storage, human time, etc).

>> You have not demonstrated this.

No.  Only that your arguments did not support the conclusion you
(apparently) marshaled them to support.  It's not that I doubt the
conclusion (while it's inevitably jurisdiction-specific, I think it's
probably true in most relevant jurisdictions); I'm just calling you on
your invalid argument technique.

> resources,

Yes (most notably the recipients' inboxes and eyeball time).

> such as the current favorite mode of using hijacked zombie PCs by the
> thousands.

"such as", perhaps.  But you appeared to be arguing that the spammers
needed to use the zombie armies for economic reasons, which I think is
false - I think they do it to avoid widespread IP-based blocking.

I'm not going to try to argue that point here; I argued it in my
previous message, and nothing you said disputed it either the arguments
or the conclusion as far as I could see.

It's relevant here because antispam techniques that are grounded in
things such as the assumption that spammers are using zombies for
economic reasons will (probably) fail because their underlying
assumptions are invalid.

/~\ The ASCII				der Mouse
\ / Ribbon Campaign

---

From: David Maxwell <[email-masked]>
Date: Tue, 27 Apr 2004 12:53:39 -0400

> order to produce this reduction versus the costs required to convert 

You also need to factor in the ongoing costs to update the hashcash
mechanism.

You may need to either increase the number of bits collided, as generic
hardware capability vs cost increases, or replace the scheme, if the
hashing algorithm is broken, or specialized hardware is built.

-- 
David Maxwell, [email-masked][email-masked] -->
All this stuff in twice the space would only look half as bad!
					      - me

---

From: "william(at)elan.net" <[email-masked]>
Date: Tue, 27 Apr 2004 18:00:47 -0700 (PDT)

As I'm trying to go through emails of last week when I was on vacation 
I get somewhat tired of seeing the same arguments over and over again on 
this never-ending thread. Without specifically commenting if e-postage is 
doable or has any chance of being adapted, I'd instead like people here to 
consider the reasons why e-postage is being proposed, what are the problems
its supposed to solve and then see if there exist any other solutions that
may accomplish the same and possible not have the same likely high
implementation costs as e-postage. 

The reasons that I heard e-postage advocates make that they think e-postage
can solve are:

1. To equalize cost of email distribution (the presumption made is that 
   its cheaper for sender to send email then for recepient to process and 
   store it).

2. To make cost of sending each piece of commercial advertisement email to 
   be higher then possible profit that could result from the majority of 
   spam offers with typical low-response rate. Thus making spammers use 
   very targetted email lists with low # of complaints from those who 
   receive their emails.

Please consider if there exist other general problems that e-postage attempts
to solve and post about it as well as thereafter consider if there exist 
other solutions that may solve these problems.

Also in these and other discussions about cost of sending emails, you 
might want to consider that cost of rejecting email during initial stage 
of SMTP transmission is very low (can be considered 0 for practical purposes)
where as cost is quite real for fully SMTP received email that is thereafter
sent through  filters, classified as spam, stored for human verification, etc

-- 
William Leibzon
Elan Networks
[email-masked]

---

From: Jonathan Morton <[email-masked]>
Date: Wed, 28 Apr 2004 03:46:09 +0100

>> order to produce this reduction versus the costs required to convert

Implementation costs are pretty low - a small plugin or extra feature 
in each popular MUA, plus possibly a verifier in the MTA or MDA chain.  
Aunt Tillie's prehistoric Mac is taken care of by a plugin for Eudora 
v3, for example.  Low-power mobile devices may have a problem 
generating hashcash themselves, but their upstream provider may be able 
to do it for them, especially if they already charge (however 
indirectly) for e-mail.

There's an education cost to get users to adopt it, but this should be 
minimal compared to many other schemes.  Once the plugin/feature is 
installed, it should be possible to make both the hashcash generation 
and signature transparent to the user, except for the processing 
latency.

Whitelisting can be ignored for truly novice users, but should be easy 
to teach to most, and will improve efficiency.  Subscription to mailing 
lists and use of e-mail forwarding boxes will require adding acceptable 
"to" addresses to an internal list, which will be an interesting 
user-interface problem, but not insurmountable.

Running costs are a certain amount of CPU time on the sender side, when 
sending to a recipient who hasn't whitelisted them yet.

> hashing algorithm is broken, or specialized hardware is built.

If specialised hardware is built for one hash algorithm, it will be 
built for whatever other hash we migrate to as well, so unless the hash 
is actually cracked, we don't need to worry about changing it.  The 
solution in the case of hardware acceleration being built is to move to 
a higher bit count, and start getting Taiwan to make cheap hash 
coprocessors so that ordinary users keep up with the spammers.

Many users won't actually need the coprocessors, because they'll 
already have adequate mutual whitelists (so that hashcash is rarely 
needed) and/or decently powerful computers (which can generate even 
high values of hashcash in a reasonable time).  Users who must contact 
strangers on a regular basis, such as sales and customer service 
departments, will benefit from the coprocessors.

In this ecology, is there a place for paid-for e-stamps?  Yes there is, 
in one form or another.  How about if an "e-stamp" is nothing more than 
a hashcash token generated by a third party, to the sender's 
specifications on the sender's payment?  That way, verification is no 
harder than for hashcash (ie. almost trivial), there's no need for 
inter-vendor settlements, there's almost no barrier to entry for 
vendors and there's no limit to scaling.  It also means that hashcash 
becomes available to all, no matter what their hardware.

The vendors are also in a good position to upgrade to coprocessor 
hardware, if and when it becomes necessary - which might, for 
particularly successful vendors, be before the spammers complete 
*their* prototype.  It means Aunt Tillie doesn't need to find and buy a 
coprocessor for her Mac IIcx in order to file her tax return on time, 
or join a gardening discussion list.

A popular argument as to why e-postage requires a micropayment system 
is that the money should go to the recipient.  I don't think the money 
needs to go that far - just the value.  We value having a nice, clean 
inbox - isn't that enough?

---

From: John Levine <[email-masked]>
Date: 28 Apr 2004 03:56:09 -0000

>Please consider if there exist other general problems that e-postage
>attempts to solve and post about it as well as thereafter consider if
>there exist other solutions that may solve these problems.

3. To improve delivery rates for legitimate bulk mailers.

4. To make vendors of e-postage systems rich.

Of all the arguments advanced for e-postage, #3 is the only one that
ever made sense, but there are approaches other than per-message
metering that address that problem.  Look at Ironport's Bonded Sender,
for example.

Regards,

---

From: Seth Breidbart <[email-masked]>
Date: Tue, 27 Apr 2004 23:11:04 -0400 (EDT)

Jonathan Morton <[email-masked]> wrote:

> is actually cracked, we don't need to worry about changing it.

Changing the hash makes the specialized hardware worthless; if it's
spammers who paid for it, that raises their costs.

>  The solution in the case of hardware acceleration being built is to
> move to a higher bit count,

Thereby preventing my mother on her 486 from sending 3 messages a day.

> and start getting Taiwan to make cheap hash 

How does that plug into a 486?

>  Users who must contact strangers on a regular basis, such as sales
> and customer service departments, will benefit from the
> coprocessors.

Why would they be contacting strangers?  They would generally be
_replying_, so should expect to be whitelisted.

Sales and customer service departments should expect to _receive_ lots
of mail from strangers, so if they set their prices too high, they
lose business.

Seth

---

From: "Chris" <[email-masked]>
Date: Wed, 28 Apr 2004 14:07:49 +0930

An e-postage system would need to account for the every day person. why
should they be charged for sending what is currently free?

So if we take that into consideration what is the limit on the number of
emails for free or charged 10,20 per day ?

Who polices that level. what about China who polices it there?

Ok set the level at zero. the average Joe will cop it sweet if it keeps spam
out of their mail box.

Does anyone here think e-mail will survive beyond a fee ?

If so go ahead and introduce a fee. see how long it takes before an
alternative becomes available.

I will start writing one as soon as e-postage looks inevitable!

Regards
Chris

P.S. How many of you would subscribe to this list if it was going to cost
$0.20 every time
And who pays for the duplicates we all receive?

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]]On Behalf Of John
> Levine
> Sent: Wednesday, 28 April 2004 1:26 PM
> To: [email-masked]
> Cc: [email-masked]
> Subject: Re: [Asrg] My take on e-postage
>
>

---

From: Barry Shein <[email-masked]>
Date: Wed, 28 Apr 2004 17:04:07 -0400

Well, for starters I want to thank you for being brutally honest about
the concerns regarding e-postage because I think what you say is
behind every other criticism. That said...

 > should they be charged for sending what is currently free?

Because the current totally free system isn't working very well as
evidenced by our convening here (that is, spam!)

Unlimited free resources tend to get abused if there's some way to
profit from that use. And that's about where we are right now.

 > emails for free or charged 10,20 per day ?

One would imagine it'd become a marketing issue, just like the monthly
price of a connection and how fast that is, etc.

 > Who polices that level. what about China who polices it there?

Again, the market.

As to China, this is probably the least of China's problems. Do we
really think we can solve all of China's problems right here or should
even take them into account?

How about the fact that all the e-mail headers and SMTP etc not to
mention the RFCs are in English? Don't you think that poses some
disadvantage to the average Chinese person? How would you like it if
all that were in Chinese?

It's not somewhere we're really set up to go here.

 > Does anyone here think e-mail will survive beyond a fee ?

If the fee is reasonable, like zero for most common, personal usage,
etc, yes.

 > I will start writing one as soon as e-postage looks inevitable!

Yeah well you could also try setting up your own phone and postage
systems and tell us how it works out.

 > P.S. How many of you would subscribe to this list if it was going to cost

Who suggested $.20? Who suggested it'd be recipient-pays?

 > And who pays for the duplicates we all receive?

Who suggested it'd be recipient-pays?

-- 
        -Barry Shein

---

From: Barry Shein <[email-masked]>
Date: Wed, 28 Apr 2004 16:40:24 -0400

3. a content-neutral way to control the problem.

It may not be the only possible approach, but the hidden problem with
many other approaches is that they still leave the problem of who gets
to decide what is spam and what is not, particularly at the
infrastructure level.

Put another way for those not following, being able to pay your way
tends to be fair in some generally agreed sense, at least it tends to
be judgement-neutral as to the content.

On the other hand, having to establish some sort of bureaucracy to
decide what is spam and what is not could be a very unpleasant road to
start down.

Imagine if the post office would only deliver your mail if they
thought you had something worthwhile to say.

What a step backwards.

Before 1989 you couldn't buy a connection to the internet unless you
could show some bona-fide usage (defense contracting, and towards the
very end of that era, being a university), and then if you were
approved hook-up was basically free.

When I first began getting the general public onto the net for merely
having $20 to spend in 1989 yes, people raved that it was outrageous
that what was previously free was now being charged for, where would
this lead!?

I think it all worked out mostly ok, regardless of the protestations
of the demagogues who insisted that the net should be free and they
alone should have the power to decide who gets access to that free
resource.

Because that's the way that goes. Either it's for sale, or eventually
someone has to have the power to regulate the resources by policy.

Worth a thought, perhaps.

-- 
        -Barry Shein

---

From: "Chris" <[email-masked]>
Date: Thu, 29 Apr 2004 11:14:55 +0930

in reply

> price of a connection and how fast that is, etc.

Marketing drives cost down, not up. take a look at bandwidth charges now and
5 years ago.

If I was to sell a hosting service and wanted to beat the competition I
might say "email at only 10c per 10,000 or get your hosting here and we will
throw in free email!

if you have to "imagine" something perhaps you have not considered all
possibilities.

>  > Who polices that level. what about China who polices it there?

Perhaps I was not clear enough. I was talking about e-mail spewing out of
places like China.
Do you think they will stop it? and if they do a hundred other countries
will take it up.
do we wholesale block entire countries? Does that become censorship?

> systems and tell us how it works out.

Take a look at all the other p2p programs, e-mail could become irrelevant.
If you don't think a lone group of programmers can introduce such a system
look at the software you use everyday
especially open source, Linux and Apache are two prime examples.

To compare an e-mail style system with a bricks, mortar, hardware and
employee system is simply trying to fool the more gullible of us, there is
simply no comparison.

Furthermore the bricks and mortar and hardware are all in place. all you
need is the enthusiasm. add a fee to e-mail and overnight you create the
enthusiasm.

Many Many programmers would see such fees as an attack on the freedom of the
internet. an attempt by governments to shut down the free flow of
information under the GUISE of spam control.

> Who suggested it'd be recipient-pays?

I wasn't in general, but for a list such as this it is inevitable. does the
ASRG pay? of course not. For a list like this it must be recipient pays.

Who else would?

Regards
Chris

> From: [email-masked] [mailto:[email-masked]]On Behalf Of Barry
> Shein
> Sent: Thursday, 29 April 2004 6:34 AM
> To: Chris
> Cc: John Levine; [email-masked]; [email-masked]
> Subject: RE: [Asrg] My take on e-postage
>
>
>

---

From: Barry Shein <[email-masked]>
Date: Wed, 28 Apr 2004 23:03:17 -0400

> Marketing drives cost down, not up. take a look at bandwidth charges now and

(Just to be picky, by "costs" you mean "prices", right?)

Well, if you said "in the case of bandwidth marketing drove the prices
down, not up" perhaps I'd agree, but I'd be hard-put to agree that's
some sort of universal principle, that it always drives prices down.

For example, in the case of MS their aggressive marketing gave them
enough of an effective monopoly in some software areas that they could
raise prices (and costs.) That's not too obscure an example is it?

 > might say "email at only 10c per 10,000 or get your hosting here and we will

Unless there were costs, something akin to settlement, where you had
to pay for the amount of email that flowed through your system and,
presumably, somehow pass those costs on to your customers.

Obviously if we're giving away free stamps then it ultimately doesn't
matter much what stamp you stick on something, may as well print your
own.

 > do we wholesale block entire countries? Does that become censorship?

Well, it'd certainly be reasonable, after some transition period, to
only accept e-mail with a valid e-postage stamp.

Is that censorship? I dunno. Is forcing them to use SMTP censorship?

 > Take a look at all the other p2p programs, e-mail could become irrelevant.

If we could start by re-inventing the entire e-mail system from
scratch then I don't think solving the spam problem is all that
difficult.

I believe most everyone agrees with that.

But you've got this little problem like a billion or two computers out
there who already do e-mail this way, and firewalls and corporate
policies and routers and servers etc.

One nice thing about e-postage is that it could, in theory, be slipped
right w/o particularly interfering with end-users. For example, for an
entire corp it could be done at the edge server, or at the ISP by some
agreement.

It's not unique in that regard, but it's useful to keep in mind that
this is a very important kind of quality for a proposed solution.

 > especially open source, Linux and Apache are two prime examples.

No problem with that.

Um, what are they gonna do when they're flooded with spam through this
new system?

How does painting the car yellow make it run faster? etc.

 > information under the GUISE of spam control.

You do understand the difference between free as in beer and free as
in speech, right?

Does having to affix postage to your letters constitute an
infringement on your freedom?

 > ASRG pay? of course not. For a list like this it must be recipient pays.

The sender?

-- 
        -Barry Shein

---

From: "Chris" <[email-masked]>
Date: Thu, 29 Apr 2004 14:05:28 +0930

> (Just to be picky, by "costs" you mean "prices", right?)

just to be equally picky outside of a monopoly, prices follow costs.

> raise prices (and costs.) That's not too obscure an example is it?

So you are proposing a monopoly to control pricing? Where are the market
forces you spoke of previously, you cannot have it both ways.

> only accept e-mail with a valid e-postage stamp.

well if we are going to implement that sort of infrastructure then why not
just identify the sender with a digest of some sort why make it a "cost"
item

> I believe most everyone agrees with that.

Yes

> policies and routers and servers etc.

Billions? one or two in five for every head of the population. more
exageration I'd say

> entire corp it could be done at the edge server, or at the ISP by some

Isnt that re-inventing the mail system.
admittedly not for the "billions" of end users but the same goes for every
other system

> You do understand the difference between free as in beer and free as

any implementation of a charge would be considered as an impediment to free
speech.
I didn't say it had to make sense. But I can assure you many people would
think this way.

its more about resistance to change.

> How does painting the car yellow make it run faster? etc.

perhaps the new software would be designed to eliminate spam
See your own comments above.
(Red is the faster colour by the way)

>  > ASRG pay? of course not. For a list like this it must be

the sender *is* the ASRG or at least the list manager

I send one email, the ASRG then distributes it to all recipients.

Are you saying I should attach an open cheque to my email and say "charge
this with as many recipients as you have on the list"?

or perhaps you are saying that one charge one email regardless of the number
of recipients?

There is a slight flaw there.

Regards
Chris

> From: Barry Shein [mailto:[email-masked]]
> Sent: Thursday, 29 April 2004 12:33 PM
> To: Chris
> Cc: Barry Shein; John Levine; [email-masked]; [email-masked]

---

From: Eric Rescorla <[email-masked]>
Date: Wed, 28 Apr 2004 22:30:23 -0700

> price of a connection and how fast that is, etc.

I don't think that this argument works.

We've got an activity (e-mail marketing) which is profitable
for individuals to engage in but produces a large negative
externality (principally the load on people's mailboxes and
the costs they bear to filter out the spam). The e-postage
solution is basically a Pigouvian tax on spamming, forcing
forcing the spammers to bear the cost externality rather than
letting them impose it on the rest of us.

Purely for the purpose of illustration, imagine we imposed
an actual tax on every e-mail sent. In order to discourage
spamming [0], each e-mail sender has to actually pay for
each message. Obviously, your ISP can pre-pay the tax
and then bundle it as part of your service, but someone
has to pay the tax. If not, it doesn't properly discourage
the activity.

In that respect, I don't think that e-postage is any different.

-Ekr

[0] Technically speaking, to have an efficiently level of spamming,
but I think most people expect that would be close to zero.

---

From: "Tom Thomson" <[email-masked]>
Date: Thu, 29 Apr 2004 11:47:53 +0100

> approved hook-up was basically free.

Strange. I was using the internet (the network interconnecting arpanet,
nfsnet, janet, and various other xxxnets) about the end of 1985 or beginning
of 1986 wearing neither a defence contractor nor a university hat.  The
universities were certainly in at the beginning of the period (via nfsnet
and other nets in the USA, janet in the UK, earnet in the UK and much of the
rest of Europe, and various other nets).  Connection was not free - you
needed a link to an node or gateway somewhere near you, and that link cost
money.  In the US, links  from your local net to the internet were typically
40.8kbits/sec (or some multiple), in Europe 48kbits/sec and 64kbits/sec and
multiples were both common); on both sides of the pond these links were
usually leased lines (although there were packet-switched paid by traffic
volume networks too, mostly left of the pond), and the various universities,
defence contractors, research institutes (both government and
non-government), and defence agencies paid the telecommunication providers a
pretty large sum for them.  Of course a University or a research institute
wouldn't charge its faculty members and research students for use in the
course of their work, any more than a defence contractor or a government
agency would charge its employess for use in the course of their work and
maybe that's what you mean when you claim it was free; but that's a bit like
saying that because I don't pay for the desk I sit at to do my work, or the
chair I sit on, or the office they are located in, the desk, chair, and
office are free when clearly they are not - my employer pays for them.  The
various agencies (Universities, research institutes, companies) which
provided the component networks on internet paid for the communication lines
forming those too.  They also paid for the (much faster) local networks
(typically 10Mbit/sec within a small group of buildings) but that of course
was much cheaper than the longer connections.

> that what was previously free was now being charged for, where would

I realy don't understand this.  You must have come across a bunch of idiots.
It had never been free.  Of course if you were offereing some outfit like a
university or a research agency or a defence contractor the opportunity to
pay $20 per employee in addition to paying for the communications
infrastructure needed to supply a decent high-speed connection they might
have though it a little outrageous.

> alone should have the power to decide who gets access to that free

Do you have any evidence (apart from your own assertion) that such
demagogues ever existed?  There was discussion and disputation about opening
up the internet to a wider community, because those who paid for the
expensive (and in those days they were very expensive) long distance links
like for example the transatlantic link between janet and nfsnet (with its
two ends at UKC and MIT in the early days, if I recall correctly) thought
that as they were paying they had the right to excercise some control over
use of the facility - particularly since bandwidth on those long links was
pretty limited and allowing everyone on would take bandwidth away from what
the links were intended for. So the argument was about who should get access
to resources paid for by agencies like NFS, SERC, CERN, DARPA, MoD, and so
on; those organisations most certainly did NOT regard their very expensive
communications capabilities as a "free resource" - and no-one but those
organisations had any effective say in the matter.

Tom

---

From: Barry Shein <[email-masked]>
Date: Thu, 29 Apr 2004 22:30:27 -0400

> nfsnet, janet, and various other xxxnets) about the end of 1985 or beginning

Well, by nfsnet I assume you mean NSFNET, as in the US National
Science Foundation, came into being in 1988, JANET first started IP
service in 1991, and the rest of your note is just about as reliable
for facts (which is to say, not at all.)

But, fwiw, I probably should have said "internet via DARPAnet" rather
than just internet although, as with the assertion above, you seem to
have created a lot more interconnections than existed (the "very end
of that era" was a reference to the 1988 NSFNET.)

-- 
        -Barry Shein

---

From: "Tom Thomson" <[email-masked]>
Date: Fri, 30 Apr 2004 11:47:12 +0100

> for facts (which is to say, not at all.)

JANET startd internal use of IP in 1991, having used a variety of other
protocols (mostly X25 over wide area, ECMA transport and various home-growns
over local area) for a long time before that. But the "internet" didn't
refer to the use of IP, but to the interconnection of the various networks,
and connections between the Joint Academic Network and various other
networks (including academic netwrorks in the US and elsewhere in Europe)
was achieved using gateways which converted between different local network
standards long before that date.  If you mean "networks using the IP defined
in RFC0791" then fine, your dates are right.  If you mean the network which
grew from the interconnection of a large collection of individual networks
in various parts of the world your dates are completely wrong.  When you
said "internet" I assumed you meant the latter (the internet still has many
subnets which are gatewayed with protocol converters, although it's now much
more common to use IP over the top of the local network layer).

> of that era" was a reference to the 1988 NSFNET.)

OK, NSFNET is 1988;  there were plenty of Universities with access to
Darpanet before then, and there were several inter-university networks
before then, and there were various interconnections between those various
inter-university netwroks before then.

Whatever the dates, the main point remains: there was no "free resource" and
none of the people who were paying for the (very) expensive network
infrastructures that formed the internet (whether by that we mean the
interconnecting network that had joined up all those individual networks, or
the network pervaded by IP which it subsequently eveolved into) were
interested in providing a free ride for non-contributors.

Tom

---

From: Barry Shein <[email-masked]>
Date: Fri, 30 Apr 2004 17:19:05 -0400

Well anyhow the point which you seem to have lost, and which might
have some possible relevance to this discussion, is really very
simple:

Prior to around the Summer of 1989, in The United States of America*,
you could not buy a direct conection to the ARPAnet for money, such
connections were not for sale to the general public.

In order to get a connection, you had to be a qualifying institution
which, prior to NSFnet in 1988, meant you had a demonstrable research
need for a connection of interest to DARPA, and a sponsor.

This mainly meant that you had to have some significant research
contract or grant work with DARPA, ONR, or some other research branch
of the US military. Occasionally an NSF grant would be declared as
qualifying but usually that's because someone felt the tie-in to an
approvable agency existed.

Even the few non-US sites were justified under this requirement.

If you were approved, the funds for hookup (other than whatever bits
you needed to plug it into a computer or LAN on your end) were
included in the approval.

HENCE:

You could only (in effect) get a connection to the ARPAnet for FREE
(from the point of the recipient, applicant), you couldn't BUY your
way in (BBN's CSNET X.25 hookup might be an arguable exception but
it's not worth bickering, I think they managed to get maybe 4
customers of which only one, Apple, ever really paid.)

OBVIOUSLY it wasn't free for DARPA or whomever was providing the
actual funds for the connection but that's not interesting.

Then NSFNET started providing hookups to Universities in the US. But
you had to be a university. They might pay or not, it's a bit
complicated and not worth going into here.

The point was that you had to qualify. You couldn't just buy a
connection.

Which brings us to SPAM.

If we don't devise a method to pay your way, such as e-postage, then
the other choice is, like the ARPAnet, someone would have to vet
whether you get access or not based on some other criteria.

Now, granted (ahem) DARPA handled this quite well but then again it
was a nearly unknown (to the general public) research network with
around 200 member sites at its peak (pre-NSFNET.)

The fear is that if you re-create that sort of environment in today's
internet, for email, by coming up with some content-sensitive criteria
for who can send mail and who can't and under what conditions you'll
of necessity have to come up with some sort of vetting process, a
bureaucracy, demagogues, who make the decision.

Bear that in mind as others make proposals that wave their hands about
what is spam and what is not.

They are probably running for demagogue (or just lack the foresight to
consider this inevitability.)

* And I believe this was generally true elsewhere but you won't
believe me so what the hell I'll limit my comment to the USA as it's
just as valid.

-- 
        -Barry Shein