There is a need to improve the use of whitelists and blacklists in fighting spam.Much spam also comes from addresses claiming to be on common domains such as yahoo.com, msn.com, aol.com, and One such technique is to allow e-mail recipients to specify a list of addresses, domains, and/or top-level domains to be always blocked or automatically allowed.The “block” list is often referred to as a “blacklist”, while the “allow” list is often referred to as a “whitelist”.illustrates the method of the present invention as having three generic steps: 11, 12, and 13.In step 11, the actual IP address 23 of sending computer 21 is determined.Blocking these domains would, for most computer users, block too much legitimate e-mail.Furthermore, many spammers falsely indicate that they are sending e-mails from such common domains when, in reality, they are not.
Steps 11, 12, and 13 may be performed by one or more modules associated with recipient computer 26 and/or with one of the MTA's 25.
These and other more detailed and specific objects and features of the present invention are more fully disclosed in the following specification, reference being had to the accompanying drawings, in which: As used throughout this specification including claims, the following terms have the following meanings: “OSI” is the Open System Interconnect model developed by the International Standardization Organization (ISO) in 1984. It operates at the transport layer (layer 4) of the OSI model to establish data transmission reliability. “IP address” is the unique address of a computer that is coupled to the Internet.
This model, described at describes how data is transferred from an application on one computer to an application on another computer. The IP address has the form #.#.#.#, where each # is a number from zero to 255. “DNS address” is an address of a computer, complying with the DNS and expressed in a form that is relatively user friendly compared with the IP address. In this address, “fenwick” is a domain and “.com” is the top-level domain. “SMTP” is the Simple Mail Transfer Protocol, a protocol which currently governs all e-mail sent over the Internet.
The inspiration behind blacklists and whitelists is the observation that most computer users exchange e-mail with a relatively small and fixed set of addresses.
These addresses are on a smaller list of domains, and these domains are on an even smaller list of top-level domains.