# US 8,751,808 B2 · Method and system for sharing trusted contact information > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,751,808 B2 - Document ID: US8751808B2 - Status: Granted - Kind: B2 - Application number: 12/943,982 - Filed: 2010-11-11 - Published: 2011-05-12 - Granted: 2014-06-10 - Earliest claimed: 2009-11-12 - Applicants: Roy Gelbard; Ran M. Bittmann - Inventors: Roy Gelbard; Ran M. Bittmann - Web page: https://patentgrep.com/patent/US8751808B2 ## CPC - H04L 51/212: using filtering or selective blocking - H04L 9/3236: {using cryptographic hash functions} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method and system for sharing trusted contact information between trusted, known and unknown parties, without revealing the contact information itself, thus protecting the party defined in the contact from possible unsolicited messages known as “Spam”. Addresses of trusted senders are encrypted using a one-way encryption and stored in a whitelist repository that can be shared by different users. When a message is received, its senders address is extracted, encrypted using the same encryption method, and compared if it is found in the whitelist repository. ## Claims ### Claim 1 A method for enabling two or more parties to share contact information by sharing a whitelist without revealing the content of said whitelist and for permitting a party sharing such a whitelist to identify a received message as coming from a trusted sender, the method comprising the steps of: (i) creating a whitelist of encrypted addresses of trusted users that are approved for sending messages using a one-way encryption method producing an encrypted sender's address, wherein the one-way encryption method can produce an encrypted address from a non-encrypted address but the non-encrypted address cannot be determined based on the encrypted address; (ii) sharing said whitelist of encrypted addresses of trusted users among two or more parties; (iii) when a message to be approved is received by a party sharing said whitelist of encrypted addresses of trusted users, extracting from the message its sender's address; (iv) encrypting said sender's address according to the same one-way encryption method used in step (i), thereby producing an encrypted senders address; and (v) verifying if said encrypted sender's address is present in said whitelist containing encrypted addresses of trusted sender addresses encrypted by said one-way encryption method and identifying a received message as coming from a trusted sender only if said encrypted sender's address is present in said whitelist of encrypted addresses of trusted users. ### Claim 2 (depends on 1) The method according to claim 1, wherein said one-way encryption method is a hashing function. ### Claim 3 (depends on 1) The method according to claim 1, wherein said received message is an e-mail message, instant message, fax message, Short Message Service (SMS) message, telephone call, Voice over IP (VoIP) call or any combination thereof. ### Claim 4 (depends on 1) The method according to claim 1, wherein a plurality of whitelists are maintained in a whitelist repository, each whitelist containing encrypted addresses of trusted senders. ### Claim 5 (depends on 4) The method according to claim 4, wherein trusted sender addresses and the whitelist repository are managed at separate devices, computers or locations. ### Claim 6 (depends on 4) The method according to claim 4, wherein said plurality of users share encrypted addresses of trusted senders via peer to peer networks. ### Claim 7 (depends on 4) The method according to claim 4, wherein said plurality of users are members of the same social network. ### Claim 8 (depends on 4) The method according to claim 4, wherein said plurality of users use the same web-based email program. ### Claim 9 (depends on 4) The method according to claim 4, wherein at least one of said encrypted addresses or at least one said whitelists or both comprise one or more tags. ### Claim 10 (depends on 9) The method according to claim 9, wherein said one or more tags represent the credibility of an encrypted sender address, wherein the unencrypted sender address is unknown. ### Claim 11 (depends on 9) The method according to claim 9, wherein said one or more tags represent the credibility of a known provider of a whitelist. ### Claim 12 (depends on 9) The method according to claim 9, wherein received messages are classified based on tags of encrypted sender addresses or whitelists or both. ### Claim 13 A system for enabling two or more parties to share contact information by sharing a whitelist without revealing the content of said whitelist and for permitting a user sharing said whitelist to identify a received message as coming from a trusted sender, the system comprising: (i) a whitelist repository maintaining one or more whitelist shared by two or more parties, each said whitelist comprising encrypted addresses of trusted users that are approved for sending messages, the encrypted addresses being created using a one-way encryption method producing an encrypted sender's address, wherein the one-way encryption method can produce an encrypted address from a non-encrypted address but the non-encrypted address cannot be determined based on the encrypted address; (ii) a message handler that (a) receives a message to be approved, (b) extracts from the message its sender's address, (c) encrypts said sender's address according to the same one-way encryption method used to create the encrypted addresses in the whitelist, thereby producing an encrypted sender's address, and (d) sends the encrypted sender's address to a verification server; (iii) a verification server that verifies if said encrypted sender's address is present in said whitelist repository containing addresses of trusted sender addresses encrypted by said one-way encryption method, and approves a received message as coming from a trusted sender only if said encrypted sender's address is present in said whitelist repository. ### Claim 14 (depends on 13) The method according to claim 13, wherein said received message is an e-mail message, instant message, fax message, Short Message Service (SMS) message, telephone call, Voice over IP (VoIP) call or any combination thereof. ### Claim 15 (depends on 13) The system according to claim 13, wherein said whitelist repository contains a plurality of said whitelists. ### Claim 16 (depends on 15) The system according to claim 15, wherein at least one of said encrypted addresses or at least one of said whitelists or both comprise one or more tags. ### Claim 17 (depends on 16) The method according to claim 16, wherein said one or more tags represent the credibility of an encrypted sender address, wherein the unencrypted sender address is unknown. ### Claim 18 (depends on 16) The method according to claim 16, wherein said one or more tags represent the credibility of a known provider of a whitelist. ### Claim 19 (depends on 16) The method according to claim 16, wherein received messages are classified based on tags of encrypted sender addresses or whitelists or both. ### Claim 20 A computer-usable memory having computer readable instructions stored thereon for execution by a processor to perform a method for enabling two or more parties to share contact information by sharing a whitelist without revealing the content of said whitelist and for permitting a user sharing such a whitelist to identify a received message as coming from a trusted sender in a whitelist repository, the method comprising the steps of: (i) creating a whitelist repository shared by two or more parties, the whitelist repository comprising one or more whitelists of encrypted addresses of trusted users that are approved for sending messages, the encrypted addresses being created using a one-way encryption method producing an encrypted sender's address, wherein the one-way encryption method can produce an encrypted address from a non-encrypted address but the non-encrypted address cannot be determined based on the encrypted address; (ii) when a message to be approved is received by a party sharing said whitelist repository of encrypted addresses of trusted users, extracting from the message its sender's address; (iii) encrypting said sender's address according to the same one-way encryption method used in step (i), thereby producing an encrypted sender's address; and (iv) verifying if said encrypted sender's address is present in the whitelist repository containing encrypted addresses of trusted sender addresses encrypted by said one-way encryption method and identifying a received message as coming from a trusted sender only if said encrypted sender's address is present in said whitelist repository of encrypted addresses of trusted users.