Method and system for selectively blocking delivery of bulk electronic mail
First Claim
1. A method of filtering e-mail comprising the steps of:
- a) determining an e-mail source address from a message;
b) accepting said message by a first computer where said source address is known to a second computer;
c) (i) autonomously issuing an e-mail message to said source address where said source address is unknown to said second computer, said e-mail message including predetermined data for use in identifying a response message, said predetermined data including a challenge request having a text statement and a digital signature;
(ii) delaying acceptance of said message by said first computer where said source address is unknown to said second computer until predetermined criteria are met, wherein a first predetermined criteria includes receipt of said response message with a modification to said text statement and with said digital signature.
3 Assignments
0 Petitions
Accused Products
Abstract
The origin address of an e-mail message is validated to enable blocking of e-mail from spam e-mail sources, by preparing, in response to the receipt of a predetermined e-mail message from an unverified source address, a data key encoding information reflective of the predetermined e-mail message. This message, including the data key, is then issued to the unverified source address. The computer system then operates to detect whether a response e-mail message, responsive to the challenge e-mail message, is received and whether the response e-mail message includes a response key encoding predetermined information reflective of a predetermined aspect of the challenge e-mail message. The unverified source address may be recorded in a verified source address list. Thus, when an e-mail message is received, the computer may operate to accept receipt of a predetermined e-mail message on condition that the source address of the predetermined e-mail message is recorded in the verified source address list and alternatively on condition that the predetermined e-mail message includes the response key.
543 Citations
24 Claims
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1. A method of filtering e-mail comprising the steps of:
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a) determining an e-mail source address from a message;
b) accepting said message by a first computer where said source address is known to a second computer;
c) (i) autonomously issuing an e-mail message to said source address where said source address is unknown to said second computer, said e-mail message including predetermined data for use in identifying a response message, said predetermined data including a challenge request having a text statement and a digital signature;
(ii) delaying acceptance of said message by said first computer where said source address is unknown to said second computer until predetermined criteria are met, wherein a first predetermined criteria includes receipt of said response message with a modification to said text statement and with said digital signature. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A spam filter system for blocking the acceptance of e-mail from unverifiable sources, said system comprising:
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a) a filtering computer system coupleable to a network for the exchange of e-mail messages; and
b) a repository coupleable to said filtering computer system that stores first and second e-mail source lists, wherein said filtering computer system accepts receipt of e-mail having an e-mail source identified on said first e-mail source list, rejects receipt of e-mail having an e-mail source identified on said second e-mail source list, and accepts receipt of e-mail including predetermined data, wherein said predetermined data includes receipt of a response message with a modified text statement and with a digital signature. - View Dependent Claims (11, 12, 13, 14, 15)
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16. A method of operating a computer for the purpose of validating the origin address of an e-mail message to enable blocking of e-mail from spam e-mail sources, said method comprising the steps of:
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a) preparing, in response to the receipt of a predetermined e-mail message from an unverified source address, a data key encoding information reflective of some aspect of said predetermined e-mail message;
b) issuing a challenge e-mail message including said data key to said unverified source address; and
c) detecting whether a response e-mail message, responsive to said challenge e-mail message, is received and whether said response e-mail message includes a response key encoding predetermined information reflective of a predetermined aspect of said challenge e-mail message. - View Dependent Claims (17, 18)
a) recording, in response to receipt of said responsive key, said unverified source address in a verified source address list; and
b) accepting receipt of a predetermined e-mail message on condition that the source address of said predetermined e-mail message is recorded in said verified source address list and alternatively on condition that said predetermined e-mail message includes said response key.
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18. The method of claim 17 wherein said response key is provided in said challenge e-mail message so as to be returned with any automatic return of said challenge e-mail message as said response e-mail message.
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19. A system for discriminating between messages categorizable as first or second message types exchangeable between first and second computer systems via a communications network, wherein messages are directed from originators to recipients, said system comprising:
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a) an authentication computer system associated with a predetermined recipient, said authentication computer system being coupleable to said communications network to allow receipt of a predetermined original message directed to said predetermined recipient;
b) a database of identified originators operable to provide a determination of whether a predetermined originator is identified in said database, said determination being accessible by said authentication computer system, wherein said authentication computer system includes means, responsive to the state of said determination, for issuing a predetermined reply message to said predetermined originator, said predetermined reply message including an encoded digital predetermined signature, and means, responsive to the receipt of a predetermined response message including data derived from said predetermined signature, for validating said data and causing said predetermined originator to be added to said database. - View Dependent Claims (20, 21, 22, 23, 24)
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Specification