The Penny Black Project is a
Microsoft Research
Microsoft Research (MSR) is the research subsidiary of Microsoft. It was created in 1991 by Richard Rashid, Bill Gates and Nathan Myhrvold with the intent to advance state-of-the-art computing and solve difficult world problems through technologi ...
project that tries to find effective and practical ways of fighting
spam
Spam may refer to:
* Spam (food), a canned pork meat product
* Spamming, unsolicited or undesired electronic messages
** Email spam, unsolicited, undesired, or illegal email messages
** Messaging spam, spam targeting users of instant messaging ( ...
. Because identifying spams consumes a recipient's time, the idea is to make the sender of emails "pay" a certain amount for sending them. The currency or the mode of payment could be
CPU cycle
The instruction cycle (also known as the fetch–decode–execute cycle, or simply the fetch-execute cycle) is the cycle that the central processing unit (CPU) follows from boot-up until the computer has shut down in order to process instructions ...
s,
Turing test
The Turing test, originally called the imitation game by Alan Turing in 1950, is a test of a machine's ability to artificial intelligence, exhibit intelligent behaviour equivalent to, or indistinguishable from, that of a human. Turing propos ...
s or
memory cycles. Such a payment would limit spammers' ability to send out large quantities of emails quickly.
The project's name is derived from the
Penny Black
The Penny Black was the world's first adhesive postage stamp used in a public postal system. It was first issued in the United Kingdom (referred to in philatelic circles as Great Britain), on 1 May 1840, but was not valid for use until 6 May. ...
, the world's first adhesive stamp used for prepaid postage.
Objective
The goal of the project is to move the e-mail costs from the receiver to the sender. The general idea is that if the sender must prove that they have expended a certain amount of effort specifically for the receiver and the message alone.
The project aims to devise a method to do this without introducing additional challenge-response mechanisms and third parties, and without requiring extra maintenance and updates, while retaining the current architecture of the e-mail system.
Ticket server
One of the project's ideas was the "ticket server", a credit-based method for validating emails. Tickets would be required to perform actions, such as sending emails. There are three operations the ticket server provides: "request ticket", "cancel ticket", and "refund ticket".
The server would allow the user to request a ticket in exchange for a
proof of work: expending
CPU cycle
The instruction cycle (also known as the fetch–decode–execute cycle, or simply the fetch-execute cycle) is the cycle that the central processing unit (CPU) follows from boot-up until the computer has shut down in order to process instructions ...
s solving hard algorithms with processing power,
Turing test
The Turing test, originally called the imitation game by Alan Turing in 1950, is a test of a machine's ability to artificial intelligence, exhibit intelligent behaviour equivalent to, or indistinguishable from, that of a human. Turing propos ...
s, or even just by paying money. The server could also cancel a ticket. For example, after receiving an email with a ticket, the receiver could request the ticket to be cancelled so it cannot be reused. The person who cancels a ticket also has the option to refund the ticket to the sender. This causes the original sender to regain a new ticket. For example, a user might refund a ticket that came with an email if it was not spam.
Using this, friendly and trusted emails would have little to no cost as tickets would be frequently refunded. However, spammers would be required to invest either a lot of computing time or money in order to create enough tickets to send large numbers of e-mails.
See also
*
Proof-of-work system
*
Hashcash
Hashcash is a proof-of-work system used to limit email spam and denial-of-service attacks, and more recently has become known for its use in bitcoin (and other cryptocurrencies) as part of the mining algorithm. Hashcash was proposed in 1997 by Adam ...
*
Internet Mail 2000
Internet Mail 2000 is an Internet mail architecture proposed by Daniel J. Bernstein (and in subsequent years separately proposed by several others), designed with the precept that the initial storage of mail messages be the responsibility of the ...
*
Anti-spam techniques
Various anti-spam techniques are used to prevent email spam (unsolicited bulk email).
No technique is a complete solution to the spam problem, and each has trade-offs between incorrectly rejecting legitimate email (false positives) as opposed to ...
References
External links
An overview of the Penny Black Project from Microsoft(archived fro
the original
{{Microsoft Research
Anti-spam
Microsoft Research
Research projects