15. Mew $B$NMh$?F;(B

$BLr$K$ON)$A$^$;$s$,!"(BMew $B$NNr;K$r$R$b$H$$$F$_$^$7$g$&!#(B

15.1 mh-e $B$+$i$NC&5Q(B
15.2 Mew $B$NCB@8(B
15.3 PGP $B$H$N=P2q$$(B
15.4 MH $B$+$i$NFHN)(B
15.5 $B%K%e!<%9$NE}9g(B

15.1 mh-e $B$+$i$NC&5Q(B

1993$BG/$N=)$K(B WIDE Project $B$N(B FJPEM $B$N<B83$K;22C$7$^$7$?!#$=$N$3$m!"]/0f(B $B$5$s$,(B FJPEM $B$r(B mh-e $B$GMxMQ$7$d$9$/$9$k$?$a!"(Bmhpem $B$r:n$j$^$7$?!#(Bmhpem $B$K?(H/$5$l!"(B1994$BG/$NE_$O=$O@$NF(Hr9TF0$r7s$M$F(B mhpem $B$N2~NI$KNe$_$^$7$?!#(B

mhpem $B$O0E9f%a%C%;!<%8$r<+F0E*$KI|9f2=$9$k$*$7$c$l$J%W%m%0%i%`$G$7$?$,!"(B $B$$$/$D$+LdBj$,$"$j$^$7$?!#Bg$-$JLdBj$O!"(Bmh-e $B$,4JC1$K3HD%$G$-$J$$=@Fp(B $B$K7g$1$?%W%m%0%i%`$@$C$?$3$H$G$9!#I|9f2=$7$?%a%C%;!<%8$O!"<!$KFI$`$H$-$O(B $BB.$/$J$k$h$&J]B8$7$?$$$H;W$$$^$9$,!"(Bmh-e $B$r2~NI$9$k$N$OFq$7$$$N$G$9!#(B mh-e $B$,%P!<%8%g%s%"%C%W$7!"(Bmhpem $B$,?7$7$$(B mh-e $B$GF0$+$J$+$C$?$H$-!"Cx<T(B $B$O@Z$l$^$7$?!#(B

$BI|9f2=$7$?(B PEM $B$rJ]B8$7$?$$!#(BMIME $B$bJ]B8$7$?$$!#$I$&$7$F!"4JC1$K(B MIME $B$r(B $B<h$j07$($k%$%s%?!<%U%'%$%9$,$J$$$N$+!#$J$<!"J#?t$N%a%C%;!<%8$+$i4JC1$K0z(B $BMQ$G$-$J$$$N$+!#%^!<%/$r6n;H$7$FLLGr$$$3$H$,$G$-$J$$$J$s$F!#%a%C%;!<%8$N(B $B@0F\$,BgJQ$J$N$O$$$d$!#7k6I!"(Bmh-e $B$r2~NI$9$k$3$H$G$O!"<+J,$NM_$7$$%W%m(B $B%0%i%`$O=q$1$J$+$C$?$N$G$9!#(B

mhpem $B$N<+F0I|9f5!G=!"(Bmhasync $B$NHsF14|$J(B scan $B5!G=!"%&%$%s%I%&$NBg$-$5$r(B $BF0E*$KJQ99$G$-$k(B GNUS $B$N5!G=!"%^!<%/$rIU$1$FJ#?t$N%K%e!<%9$r<h$j07$($k(B gnus-mark $B$N5!G=!"(BVM $B$N$h$&$J@0F\5!G=!"2r@O$7$?%a%C%;!<%8$NJ]B8!"H~$7$/(B $B=@Fp$N$"$k%W%m%0%i%_%s%0%9%?%$%k(B.... $B$5$^$6$^CGJR$,Cx<T$NCf$G(B1$B$D$K$^$H(B $B$^$j;O$a$^$7$?!#(B1994$BG/(B3$B7n!"F`NI$X$N0z1[$7A0$N$3$H$G$7$?!#(B

15.2 Mew $B$NCB@8(B

1994$BG/(B4$B7n!"K\3JE*$K(B Mew $B$N@=:n$K<h$j3]$+$j$^$7$?!#0lMwI=<($N=*N;$rBT$?$J(B $B$/$F$h$$5!G=!"F0E*$J%&%$%s%I%&@_Dj!"%^!<%/!"2r@O$7$?%a%C%;!<%8$NJ]B8$J$I(B $B$O!"$*

$B$O$8$a$N:"$O(B MIME $B$r(B MIME $B%b!<%I$GI=<($7$F$$$^$7$?!#%^%k%A%Q!<%H$N%a%C%;!<(B $B%8$G(B `SPC' $B$r2!$9$H!"(BSummary $B%b!<%I$+$i(B MIME $B%b!<%I$K0\F0$7$F$$$?$N(B $B$G$9!#$7$+$7!"2NBe$5$s$O8@$$$^$7$?!"!V$J$<(B MIME $B%b!<%I$+$"$k$N!)(B Summary $B$@$1$G==J,$G$O$J$$$+!W!#L\$+$iNZ$NMn$A$k;W$$$G$7$?!#(B

$B$3$N$3$m$NBg$-$J>c32$O!"%a%C%;!<%8$N@0F\J}K!$H(B MIME $B$N:n.J}K!$G$7$?!#(B

$B3N$+$K(B VM $B$N$h$&$K!"%f!<%6$K$$$A$$$A(B Lisp $B$r=q$+$;$l$P!"@0F\$O4JC1$K$J$j(B $B$^$9!#$7$+$7!"%f!<%6$K$3$^$a$K@_Dj$5$;$k$3$H<+BN$,7y$@$C$?$N$G$9!#!V%a%C(B $B%;!<%8$N%X%C%@$+$iL58B$N2DG=$N$"$k@0F\@h$rLO:w$9$k$N$OGO

$BJ#;($J(B MIME $B$r4JC1$K:n.$9$k$K$O$I$&$9$l$P$h$$$+!)(B $B%f!<%6$K$O:n.J8K!$H(B $B$+(B MIME $B$N=q<0$J$I$NM}2r$r2!$7$D$1$k$N$O$"$s$^$j$!#0l8@bL@$9$l$P!"$@$l(B $B$G$bD>46E*$K(B MIME $B$r:n$l$k$h$&$K$7$?$$!#$3$NEz$($r$/$l$?$N$OLgNS$5$s$G$9!#(B $B!V(BMIME $B$N9=B$$C$F%U%!%$%k%7%9%F%`$K;w$F$$$k$h$M!W!#$=$&$G$9!"%7%s%0%k%Q!<(B $B%H$r%U%!%$%k!"%^%k%A%Q!<%H$r%G%#%l%/%H%j$H9M$($l$P$h$$$N$G$9!#%U%!%$%kA`(B $B:n$O$@$l$K$G$b$G$-$k$7!"%U%!%$%k9=B$$r(B MIME $B$KJQ49$9$k;E;v$O(B Mew $B$,@A$1(B $BIi$$$^$9!#(B

15.3 PGP $B$H$N=P2q$$(B

FJPEM $B$N<BAu$K5?Ld$r46$8$F$$$?Cx<T$O!"(B1994$BG/$N=i2F(B PGP $B$H=P2q$$$^$7$?!#(B $B$=$N$3$m$O(B PGP 2.5$B!"$D$^$j!"(BMIT $B$,(B RSAREF $B$r;H$C$F!"(BRSA $B$NFC5v$KDq?($7$J(B $B$$Hs>&MQ$N(B PGP $B$rLO:w$7$F$$$?;~4|$G$9!#(BPGP 2.6 $B$N%j%j!<%9$K$h$C$F!"(BPhil $B$H(B RSADSI $B$OOB2r$7$^$7$?$,!"(BRSAREF $B$r;H$C$F$$$k(B 2.6 $B$OJF9q9q30$X$N;}$A=P(B $B$7$,6X;_$5$l$F$$$^$9!#(B

$B$7$+$7!"(B2.3a $B$r4p$K$7$?(B 2.6ui $B$NB8:_$rCN$j!"(BPGP $B%f!<%6$K$J$j$^$7$?!#(BPGP $B$r;O$a$F;H$C$?$H$-$N46F0$OK:$l$i$l$^$;$s!#K\Ev$K7W;;$7?T$/$5$l$?%W%m%0%i(B $B%`$G$9!#(B1995$BG/$NE_!"%5%s%G%#%(%4$G3+$+$l$?DL>N(B ISOC Security Symposium(NDSS)$B$H$$$&9q:]2q5D$K;22C$7$^$7$?!#$3$N$H$-!"%W%m%7!<%G%#%s%0(B $B$H6&$K(B O'Reilly $B$+$iH/Gd$5$l$F$9$0$N(B Simson $B$N(B PGP $B$H$$$&K\$r$b$i$$$^$7(B $B$?!#5W!9$KFI$_$U$1$C$?7f:nCf$N7f:n$G$9!#$3$N$h$&$JM}M3$+$i!"(BPEM $B$H(B MIME $B$NE}9g$h$j$b!"(BPGP $B$H(B MIME $B$NE}9g$KNO$rCm$0$h$&$K$J$j$^$7$?!#(BPGP/MIME $B$O(B $B8=:_<B83CJ3,$G$"$j!"I8=`2=$K$O$^$@;~4V$,$+$+$j$^$9!#(B

$B!V0E9f2=$H$+=pL>$O%^!<%/$GI=$;$P$$$$!W$H$$$&%"%$%G%#%"$O!"]/0f$5$s$H>pJs(B $B=hM}A49qBg2q$NO@J8$r=q$$$?$H$-$K65$($F$b$i$$$^$7$?!#%^!<%/$J$i$$$D$G$b9%(B $B$-$J$H$-$K%-%c%s%;%k$G$-$k$H$$$&MxE@$rM}2r$9$k$N$O>/$7;~4V$,$+$+$j$^$7$?(B $B$1$I!#(B

15.4 MH $B$+$i$NFHN)(B

$B!V$&$^$$<w;J$r?)$o$;$F$d$k$+$i$_$s$JJ!2,$K=89g$!W$N$+$1@<$N$b$H!"(B1997$BG/(B 4$B7n$K$=$&$=$&$?$k%W%m%0%i%^$,J!2,%I!<%`$N$"$kI4F;$K7k=8$7$^$7$?!#6e=#%7(B $B%9%F%`>pJs5;=Q8&5f=j$K%O%C%/It20$r<Z$j!"6a$/$N%O%$%d%C%H!&%j!<%8%'%s%7!<(B $B$r?2>2$K$7$F!"(B3$BGq(B4$BF|$K5Z$V(B MH $B$+$i$NFHN):n@o$,3+;O$5$l$^$7$?!#(B

$B$H$K$+$/?)$Y$k!"5$$KF~$k$^$G%O%C%/$9$k!"$H$3$H$s$^$G5DO@$9$k$H$$$&:n6H$r(B $B$J$s$I$b7+$jJV$7!"J!2,$r8e$K$9$k$3$m$K$O$[$\(B Mew $B$,(B MH $B$+$iFHN)$7!"(BIM $B$r(B $B;H$&$h$&$K$J$C$F$$$^$7$?!#(B($B$3$N=5$N%(%s%2%k78?t$,9b$+$C$?$N$O8@$&$^$G$b(B $B$"$j$^$;$s!#(B)

$B$=$N8e$b%a!<%j%s%0%j%9%H$G5DO@$r@o$o$;!"9g0U$r'$($F!"$h$&$d$/(B7$B7nF,$K%Y!<(B $B%?%j%j!<%9$K$3$.$D$1$^$7$?!#(B

15.5 $B%K%e!<%9$NE}9g(B

1994$BG/=)$N(B WIDE $B9g=I$G(B Mew $B$N(B BOF(Birds Of a Feather::$B0f8MC<2q5D(B)$B$r$7$^(B $B$7$?!#$3$N(B BOF $B$G:4Ln$5$s$O!VEE;R%a!<%k$H%K%e!<%9$NCf4V$,%a!<%j%s%0%j%9(B $B%H$@$h$M!W$H$$$&K:$l$i$l$J$$8@MU$r;D$7$^$7$?!#0G$NCf$G<jC5$j>uBV$@$C$?$H(B $B$3$m$K!"0l6Z$N8w$r8+$?;W$$$G$9!#(BPerl 5 $B$,0BDj$7$F$-$?8=:_!"%K%e!<%9$NE}(B $B9g$O4V6a$KGw$C$F$$$^$9!#(B