start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue= article-no= start-page=384 end-page=390 dt-received= dt-revised= dt-accepted= dt-pub-year=2005 dt-pub=2005 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=A protection method against massive error mails caused by sender spoofed spam mails en-subtitle= kn-subtitle= en-abstract= kn-abstract=Wide spread of spam mails is one of the most serious problems on e-mail environment. Particularly, spam mails with a spoofed sender address should not be left alone, since they make the mail server corresponding to the spoofed address be overloaded with massive error mails generated by the spam mails, and since they waste a lot of network and computer resources. In this paper, we propose a protection method of the mail server against such massive error mails. This method introduces an additional mail server that mainly deals with the error mails in order to reduce the load of the original mail server. This method also provide a function that refuses error mails to these two mail servers to save the network and computer resources. en-copyright= kn-copyright= en-aut-name=YamaiNariyoshi en-aut-sei=Yamai en-aut-mei=Nariyoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OkayamaKiyohiko en-aut-sei=Okayama en-aut-mei=Kiyohiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=MiyashitaTakuya en-aut-sei=Miyashita en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=MaruyamaShin en-aut-sei=Maruyama en-aut-mei=Shin kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=NakamuraMotonori en-aut-sei=Nakamura en-aut-mei=Motonori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil= kn-affil=Okayama University affil-num=2 en-affil= kn-affil=Okayama University affil-num=3 en-affil= kn-affil=Okayama University affil-num=4 en-affil= kn-affil=Kyoto University affil-num=5 en-affil= kn-affil=Kyoto University en-keyword=Internet kn-keyword=Internet en-keyword=security of data kn-keyword=security of data en-keyword=unsolicited e-mail kn-keyword=unsolicited e-mail END