Method and system for filtering electronic messages

A method of identifying an electronic message as an unsolicited electronic message on the basis of a network location specified therein, wherein data indicative of the electronic message are stored in association with the network location, the method comprising:

• responsive to a request for access to the network location from a recipient of the electronic message, accessing data indicative of a classification of said electronic message;
• retrieving data associated with said network location, independent of data contained at the site associated with the network location, and analyzing, by use of a processor, said retrieved data so as to validate said classification of said electronic message as unsolicited or solicited;
• in response to classification of the electronic message as unsolicited, modifying, by use of a processor, the network location specified in the electronic message, wherein modifying the network location comprises:
• modifying the network location specified in the electronic message to comprise matter that represents said network location;
• and
• wrapping said matter within a link directed to an alternative network location which corresponds to a remote processing system that is different than the one corresponding to the network location specified in the electronic message;
• allowing access to the alternative network location;
• and
• in response to classification of the electronic message as solicited, allowing access to the network location specified in the electronic message.

A method of modifying an electronic message transmitted through a communications network, the method comprising:

• receiving an electronic message;
• identifying, by use of a processor, first data indicative of a first network location, the first data being independent of data contained at the site associated with the first network location, said first network location being specified within the electronic message;
• analyzing, by use of a processor, the electronic message on the basis of at least an attribute intrinsic to the message and unrelated to the first network location so as to classify the message as either a suspect message or an acceptable message;
• in response to classification of the electronic message as a suspect message, associating, by use of a processor, the first data with second data indicative of a second network location, said second network location corresponding to a remote processing system different to that corresponding to the first network location, wherein associating the first data with second data comprises:
• generating matter that represents the first data;
• and
• wrapping said matter with the second data;
• modifying the electronic message so as to include the second data;
• transmitting the modified electronic message;
• and
• in response to classification of the electronic message as an acceptable message, transmitting the unmodified electronic message.

A system for modifying an electronic message during transmission through a communications network, said electronic message having a source address and a recipient address, the system comprising:

• a network interface for receiving the electronic message before it has been delivered to a device corresponding to the recipient address;
• the system comprising a processor arranged to identify a first link specified within the received electronic message, said first link directed to a first network location, and to analyze at least the electronic message on the basis of at least one of an attribute of the first link, independent of content of the site associated with the first link, and at least an attribute intrinsic to the received electronic message so as to classify the received electronic message as either a suspect message or an acceptable message;
• wherein, in response to classification of the received message as a suspect message, the system is arranged to modify the received electronic message, wherein modifying the electronic message comprises:
• modifying the first link to comprise link matter that represents the first link;
• and
• wrapping the link matter within a second link directed to an alternative network location said alternative network location corresponding to a remote processing system different from that corresponding to the first link;
• wherein the system is further arranged to transmit the modified electronic message;
• and
• wherein, in response to classification of the received message as an acceptable message, the system is arranged to transmit the unmodified electronic message.