Re: Card Playing Protocol?

tcmay@netcom.com writes:
>Find a _reason_ to use crypto in games...

Easy.  Three quick ones.

1) If you like nice distributed "I don't need no stinkin' trusted
server" ways of doing things, it is the only way to play some virtual
games.

2) Games are very important.  (Quick: Name 10-industries which are
bigger.  ...  Betcha ya made at least one mistake.)

3) A simple game of cards is very non-threatening.  It doesn't smack
of anarchists or revolutionaries or anything frightening like that.
Those words scare a lot of people.  This is politics man, these things
matter.

Tim also writes:
>An obvious problem with crypto card games is this: what does it
>provide that is worth the extra effort of doing encryption?

I admit I originally considered a situation where the user actually
saw the crypto elements in action, I have since convinced myself that
is silly.  At least in the case of doing cards, too complicated.
Seeing the results is pretty powerful, however.

Also, remember who suggested this (today): I am a user interface
freak.  The effort is in the protocol, the user never sees it, she
only notices that she can now be part of the World Wide Duplicate
Bridge Tournament that she heard about on All Things Considered.

The effort in building the protocol?  I love that stuff.  

The effort in writing the software?  I like that stuff somewhat--but
there is possible *profit* here, I might not have to write more than
the crude 0.9 version.  Some game company might finally bring down
ITAR.  (Now that is economic might.)

The effort in CPU time or communication bandwidth?  Shit!  We are
talking a world of digital video, for christsakes!  What's a few
computrons and bauds burnt to deal a hand of go-fish?

Is there a flavor of effort I forgot?


-kb

--
Kent Borg                                                  +1 (617) 776-6899
kentborg@world.std.com                                
kentborg@aol.com                                      
          Proud to claim 32:00 hours of TV viewing so far in 1994!

Actually, I'm going to somewhat reverse direction and _encourage_ Kent
Borg to continue on with his card playing idea.

Not that my message a short while ago was condemning it, just pointing
out that one must motivate people to use something (or, even better,
cater to their natural motivations). The "castor oil" approach rarely
works. (For those younger than about 35, castor oil was once touted as
being "good for you." Actually, it has faded out before my time, but
the cultural effluvia of my childhood covered it.)

Kent writes:

> Easy.  Three quick ones.

Kent is showing the classic signs of infatuation with a new idea.
Which is good. The problem, which I'll get back to later, is that
this enthusiasm usually fades....this has been the experience on our list.

> 2) Games are very important.  (Quick: Name 10-industries which are
> bigger.  ...  Betcha ya made at least one mistake.)

I don't know, but so what? Lots of things are classed as games.
Gambling is big, but so are a lot of other things.

Nick Szabo, no longer of this list, was once very hot on creating the
"Internet Casino." I have been, too, in an abstract sense...crypto
gambling as a legal "cover" for crypto protocols, since around 1989.
But I've not worked on these protocols, so I claim no credit.

(By the way, an imnplementation of mental poker would be useful. Once
people got the idea, though, they'd probably stop playing. A lot of
games are "funny onces," to again cite 'The Moon is a Harsh Mistress.')

> 3) A simple game of cards is very non-threatening.  It doesn't smack
> of anarchists or revolutionaries or anything frightening like that.
> Those words scare a lot of people.  This is politics man, these things
> matter.

Kent is ranting here, which is good. But this still won't make people
play your game.

> Also, remember who suggested this (today): I am a user interface
> freak.  The effort is in the protocol, the user never sees it, she
> only notices that she can now be part of the World Wide Duplicate
> Bridge Tournament that she heard about on All Things Considered.
> 
> The effort in building the protocol?  I love that stuff.  

I agree the protocols are the interesting part. This is why, despite
my cynicism about people actually playing this game, I encourage Kent
to continue. 

A recurring problem we all have is one of initional wide-eyed, ranting
enthusiasm, resulting in the idea being the thread du jour for a
couple of days, followed by....silence. And nothingness. (I won't
embarrass or anger anyone here by mentioning recent examples. There
are of course various reasons things don't take off, or even clear the
launching tower.)

> The effort in writing the software?  I like that stuff somewhat--but
> there is possible *profit* here, I might not have to write more than
> the crude 0.9 version.  Some game company might finally bring down
> ITAR.  (Now that is economic might.)

A huge issue. The cryptographic primitives needs are poorly
implemented, in my opinion. "Bit commitment" is one good example. The
papers on mental poker and secret sharing are not filled with code
examples, to say the least! It took 10-12 years to get widely
available examples of something so semantically simple as RSA, and
digital cash remains in a sorry state. 

The Crypto Proceedings (to answer Kent's earlier question: the Crypto
books for 1985-87 are widely available in technical
bookstores--Computer Literacy, Stanford, many other stores--and
directly from Springer-Verlag, for about $60-80 apiece, in paperback)
provide a few mathematical details, but conversion to C code is iffy.
Ask Bruce Schneier. Complicated protocols will need building
blocks--C++ classes, Smalltalk objects and methods, whatever.

Henry Strickland is working on a TCL toolkit (TCL the
Ousterhout/Berkeley package, not the Symantec product of the same TLA
name). I'm interested in object-oriented protocol building blocks, and
spoke on this at the last physical Cypherpunks meeting.

Kent Borg could make a real contribution by implementing the several
protcols for card games. I don't think it'll be easy, but it could be
rewarding. It has not been done, generally. (Beware of "faking" parts
of the protocols with a GUI facade such as game designer might be
tempted to use...the underlying protocols must be extremely robust.)

> The effort in CPU time or communication bandwidth?  Shit!  We are
> talking a world of digital video, for christsakes!  What's a few
> computrons and bauds burnt to deal a hand of go-fish?

Slow communication has worked well for games of skill like Go and
chess, but an IRC-type speed would most likely be needed to keep
interest up in all the card games I've seen. 

> Is there a flavor of effort I forgot?

The most consistently lacking flavor of effort in these kinds of
enthusiasms is--drum roll--sustained interest. If this becomes an
abiding interest of Kent, progress could be made, perhaps in as short
as a year or so. (Beware of slapping together a Potemkin village
facade of a demo.)

Hence my encouragement that he stick with this. Implementing even a
cryptographically-secure penny matching game would be a start.

Kent, just don't get caught too much up in fantasies about Donald Trump
buying the algorithm...a _lot_ of work has to be done first.

--Tim May


-- 
..........................................................................
Timothy C. May         | Crypto Anarchy: encryption, digital money,  
tcmay@netcom.com       | anonymous networks, digital pseudonyms, zero
408-688-5409           | knowledge, reputations, information markets, 
W.A.S.T.E.: Aptos, CA  | black markets, collapse of governments.
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"National borders are just speed bumps on the information superhighway."

only notices that she can now be part of the World Wide Duplicate
   Bridge Tournament that she heard about on All Things Considered.

Duplicate games won't work on the net because the assumption is that
the players have no advance knowledge of the cards of the other
players.  Even if the same hand is dealt simultaneously to multiple
virtual tables., the differences in order of play will reveal cards
early for some players.

The hole is the sharing of information between players.

Duplicate could still be supported with physically based, but
distributed, rooms of play, using the Internet for logistical support.

   Is there a flavor of effort I forgot?

There is a non-crypto issue of how one finds playing partners without
a central server.  An IRC channel seems to have the right properties:
real-time, centrality of name, distributed information paths.  IRC
might be able to be hacked into directly.

The code to find of playing partners should integrate digital
signatures for identity, in order to make possible long scale
tournament play.

Mutual agreement should be required for the formation of a group.
Automatic agreement can always be implemented in client software.
There is likely an interesting protocol here for the negotiation of
group formation without revealing preferences that are not manifested
in the creation of a group.

I would strongly suggest the separation of the communications, user
presentation, and decision parts of the client software.  Folks should
be able to pick the presentation of the cards that they want: table
layout, card backs, etc.  Decision in current card games is currently
all by user input; the user sees the cards, decides what to do, and
clicks.  People will want to try out card playing algorithms, and you
might as well leave a hook in for them.

Eric

If I implement a card playing protocol and Okamoto & Ohta's bankless cash
system today and tomorrow morning (primarilly to verify that my primitives
work correctly) will you guys promise to pick them apart Sunday evening and
Monday?

JWS

If I implement a card playing protocol and Okamoto & Ohta's bankless cash

Bankless?  The paper I have from them (in CRYPTO '91) is not bankless.

Eric

>   If I implement a card playing protocol and Okamoto & Ohta's bankless cash
>   system today and tomorrow morning (primarilly to verify that my primitives
>   work correctly) will you guys promise to pick them apart Sunday evening and
>   Monday?

I am not a good enough cardplayer to want to play any kind of cards
for money.

however, if you implement a backgammon playing protocol (and there 
already is one in the public domain ... probably more than one) I
will not only do my best to pick it apart, but I will play anyone
else who is willing, for real (electronicized) money.

josh