Block Spam with Spoofed Domain Names

"Internet Initiative Japan Inc., one of Japan's leading Internet-access and comprehensive network solutions providers, today announced it will improve email spam filtering by introducing sender authentication on the IIJ4U and IIJmio Internet access services for retail customers starting on December 21, 2005. Through the Sender Policy Framework (SPF) (*1), a mechanism for preventing falsified sender domain names, the IP address of IIJ's originating e-mail servers will be made public in the company's DNS information, thus guaranteeing the validity of the originating server. This system makes it possible to determine if mail with an IIJ4U/IIJmio e-mail address is actually being sent from an IIJ4U/IIJmio mail server, thus effectively deterring spam using a spoofed IIJ4U/IIJmio domain name." Source: tmcnet.com