When e-mail was first developed, the network was a friendly place. Most users were researchers, and they had a vested interest in making the network work well. For the most part, they knew each other; in fact, there was a directory of every network user, including their names, physical and e-mail addresses, and phone numbers–printed on paper and weighing less than 2 pounds….In all, financial losses attributed to phishing in 2006 amounted to around $2.8 billion. Because of this, most individuals and companies have little trust in their e-mail systems, and the challenge facing e-mail administrators has evolved from filtering out the bad messages to filtering in the good….Work has been progressing for several years on an e-mail authentication technology known as DKIM (DomainKeys Identified Mail), developed collaboratively by several companies, including Cisco Systems, Yahoo, Sendmail and PGP.
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