$B!X%7%9%F%`$N5!L)J];}$N;EAH$_!Y(B

$B!{%;%-%e%j%F%#$r9M$($k:]$K$O!"0J2<$N(B7$B$D$NAX$K$D$$$F=gHV$K8!F$$9$k$N$,DLNc$G$9!#(B

application	Netscape$B$J$I!"%V%i%&%6$H$7$F$N5!G=!#(B
presentation	HTTP$B$H$7$FF@$i$l$?%G!<%?$r(BHTML$B$H$7$F(Bparse$B$7$FI=<($9$k!#(B
session		HTTP$B$J$I$N$R$H$D$N%j%/%(%9%H$r9=@.$9$k!#(B
protocol	HTTP,FTP$B$J$I!"(BOS$B$h$j>e$N%M%C%H%o!<%/%W%m%H%3%k(B
transport	TCP/IP,UDP$B$J$I!"(BOS$B$h$j2<$N%M%C%H%o!<%/%W%m%H%3%k(B
network		EtherNet 
datalink	CSMA/CD
physical	10Base-T$B$J$I!#J*M}E*$J@~!#(B


$B""%/%i%$%"%s%HB&$N%;%-%e%j%F%#$K4X$7$F=R$Y$^$9!#(B

1. physical /datalink/network/transport layer

$B%5!<%P$H$J$k%^%7%s$r(Binternet$BB&$+$i$O(BIP-reachable$B$K$7$J$$$h$&$K!"(B
$BEEDLFb$N(Bfirewall$B$NFbB&$K@_CV$9$kI,MW$,$"$k!#(B

$B$3$&$7$F!"EEDLFbIt$H(Binternet$B$N4V$K(Bfirewall$B@_CV$,$5$l$F$$$k$N$J$i$P!"(B
$B30It$+$iDL?.$r$5$l$?$j!"DL?.FbMF$r4V0c$C$F1L$i$7$F$7$^$&$3$H$O$J$$!#(B

$B$9$Y$F$NDL?.$O(BTCP/IP$B$G9T$J$o$l$k$N$G!"(B
NT$B%I%a%$%s$N6h@Z$j$d(BAppleTalk$B$N(BZone$B@_Dj$J$I$K$D$$$F$J$I$OL54X78$G$"$j!"(B
$BLdBj$H$J$i$J$$!#(BIP-reachable$B$G$"$j$5$($9$l$P$h$$!#(B

$B0J>e$N$h$&$K!"(Bphysical/datalink/network/transport layer$B$K$*$1$k0BA4@-$O!"(B
$BEEDLFb%M%C%H%o!<%/$N9=C[FbMF$K$N$_0MB8$9$k!#(B
$B30It$+$i$N%"%?%C%/$J$I$KBP$7$F$O!"(B
$BEEDL$N(Bfirewall$B$K$h$C$FKI1R$5$l$k$3$H$r4|BT$9$k!#(B

$B0J>e$NE@$K$D$$$F$N%;%-%e%j%F%#$O3NJ]$5$l$k$b$N$H$9$k!#(B

2. protocal layer

$BMxMQ<T$N%/%i%$%"%s%H(BPC$B$H!"%5!<%P$H$J$k%^%7%s$N4V$G$O!"(B
HTTP$B$K$h$kDL?.$r9T$J$&!#(B
$B$3$l$O!"EEDLFbIt$N%M%C%H%o!<%/$+$i$N%"%/%;%9$O?.MQ$G$-$k$b$N$HH=CG$7!"(B
$BDL?.$K;H$&%W%m%H%3%k$ODL>o$N(BHTTP($BJ?J8$K$h$k>pJsE>Aw(B)$B$K$h$k$b$N$G$"$k!#(B
$BEEDLFbIt$N%M%C%H%o!<%/7PO)>e$G$N>pJs$NEp$_8+$N2DG=@-$OL5;k$9$k!#(B

3. session layer

$BMxMQ<T$N%/%i%$%"%s%H(BPC$B$,!"(BHTTP$B$K$h$j%5!<%P$HDL?.$r9T$J$*$&$H$9$k$H!"(B
$B:G=i$K!"%5!<%P!<$O%/%i%$%"%s%H$KBP$7$F!"(BHTTP$B$K$N$C$H$C$F(B
$B3F%f!<%6!<$KBP$7$F8DJL$KH/9T$5$l$?%m%0%$%sL>$H%Q%9%o!<%I$NF~NO$r(B
$B5a$a$k!#(B

$B%/%i%$%"%s%H$,%m%0%$%sL>$H%Q%9%o!<%I$rF~NO$7!"(B
$B%5!<%P$G$3$l$,G'>Z$5$l$k$H!"%5!<%P$O%f%K!<%/$J%;%C%7%g%s(BID-cookie$B$rH/9T$9$k!#(B
$B0J9_$O!"$3$N%;%C%7%g%s(BID-cookie$B$K$h$C$F%m%0%$%s$7$?%f!<%6!<$N>uBVA+0\$r4IM}$7!"(B
$BDL?.$r9T$J$&!#(B

$B%5!<%P$O!"(B
$BH/9T:Q$_$N%;%C%7%g%s(BID$B$K$D$$$F$O!"$=$N%;%C%7%g%s$,G'>Z$5$l$?Aj<j$N(B
User-Agent$B$d%=%1%C%H$N(BIP$B%"%I%l%9$r5-21$7$F$$$k$N$G!"(B
$BIT@5$J%;%C%7%g%s(BID-cookie$B$dIT@5$J(BUser-Agent,IP$B$NAH$_9g$o$;$r;}$D(B
HTTP$B%"%/%;%9$K$D$$$F$O5qH]$9$k!#(B

$B%5!<%PB&$G$O!"FbItE*$K(B45$BJ,4V3V$G(BSIGALRM$B$rH/9T$7!"(B
30$BJ,0J>e7P2a$7$F$b<!$N%"%/%;%9$5$l$J$+$C$?%;%C%7%g%s>pJs$r:o=|!&L58z2=$9$k!#(B

4. presentation	layer

$BI=<($5$l$k(BHTTP$B%G!<%?$O!"(BPragma: no-cache$B$NB0@-$rM?$($i$l$F$$$k$?$a!"(B
$BI=<($5$l$k>pJs$O%G%#%9%/$K%-%c%C%7%e$5$l$J$$$h$&$K;XNa$r<u$1$k!#(B

$B$3$N$H$-!"%/%i%$%"%s%H$d(Bproxy-server$B$,(BHTTP$B4{Ls$K=>$C$F<BAu$5$l$?$b$N$G$"$l$P!"(B
$B%f!<%6!<$,%-%c%C%7%e$K4X$9$k@_Dj$r$I$N$h$&$K$7$?$+$K4X$o$i$:!"(B
$B%G!<%?$,%-%c%C%7%e$5$l$k$3$H$O$J$$!#(B
$B$3$l$K$h$j!"(B
$B%/%i%$%"%s%H(BPC$B$N%G%#%9%/$N%-%c%C%7%e%G%#%l%/%H%jFb$r8!:w$9$k$3$H$G!"(B
$B%-%c%C%7%e$5$l$?>pJs$rG'>Z$J$7$GI=<($5$;$k$J$I$N9T0Y$rKI$0$3$H$,$G$-$k!#(B

5. application layer

$B2hLL$KI=<($7$?$^$^@J$rJ|$l$F$7$^$&$3$H$rA[Dj$7!"(B
$BI=<($5$l$?(BHTML$B$NFbMF$O!"(B60$BJ,4VJ|CV$5$l$k$H(B
$B<+F0E*$K(Blogin$B2hLL$KLa$k(B(reload$B$9$k(B)$B$h$&$J=hM}$r2C$($F$"$k!#(B

$B0J>e$K$h$j!"%/%i%$%"%s%H%"%W%j%1!<%7%g%s>e$+$i$O!"(B
$B<BMQ>e==J,$J%;%-%e%j%F%#$r3NJ]$9$k$3$H$,=PMh$k!#(B



------------------------------------------------------------------------
$B""%5!<%PB&$N%;%-%e%j%F%#$K4X$7$F=R$Y$^$9!#(B

$B%5!<%PB&$N%;%-%e%j%F%#$O!"(B
$BDL>o$N(BUNIX OS$B$N%;%-%e%j%F%#(B($B%m%0%$%s%Q%9%o!<%I$K$h$k%;%-%e%j%F%#(B)
$B$K$h$k!#(B
$B$9$J$o$A!"EEDL$N(Bfirewall$B$K$h$C$FKI1R$5$l$k$3$H$rBh0l$K4|BT$9$k$b$N$H$7!"(B
$BBhFs$K!"$3$N%5!<%P%^%7%s$KIU$1$i$l$?%Q%9%o!<%I$K$h$C$FKI1R$5$l$k$b$N$H$9$k!#(B

$B%5!<%PFb$G$N%G!<%?$N%;%-%e%j%F%#$O!"(B
$B3:Ev%G%#%l%/%H%j$N%"%/%;%98"8B$r(B700$B$H$9$k$3$H$G!"(B
$BB>%f!<%6!<$+$i$N%"%/%;%9$r5qH]$9$k!#(B

$B0J>e$K$h$j!"%5!<%P%W%m%;%9C1BN$H$7$F$O==J,$J%;%-%e%j%F%#$r(B
$B3NJ]$9$k$3$H$,=PMh$k!#(B


------------------------------------------------------------------------
$B""%5!<%P$N@_CV0LCV(B

$B%M%C%H%o!<%/%H%]%m%8!<E*$K$O!"(B
$B%/%i%$%"%s%H(BPC$B$+$i(BIP-reachable$B$J0LCV!#(B

$B@_CV>l=j$H$7$F$O!"(B
$BEE8;$N8mA`:n$d%$%?%:%i!"%3!<%R!<$r$3$\$9$J$I$N!"(B
$BJ*M}E*$J>c32$N860x$rKI$2$k$h$&$J!"(B
$B%*!<%W%s%9%Z!<%9$H$O3VN%$5$l$?0BA4$J0LCV$X$N@_CV$,K>$^$7$$!#(B

$B$b$7%*!<%W%s%9%Z!<%9$K@_CV$;$6$k$rF@$J$$$N$G$"$l$P!"(B
$B4V0c$C$FEE8;$r@Z$i$J$$$h$&$KCm0U$9$k$J$I$r!"(B
$B<~0O$G:n6H$r$9$k<T$d@6A]C4Ev<T$J$IA40w$K<~CN$9$kI,MW$,$"$k!#(B


------------------------------------------------------------------------
> $BJ]<i!&1?MQ$*$h$S%H%i%V%k;~$NBP1~$H@UG$BN@)(B
> $B!&J?>o;~$NE@8!:n6H$OI,MW$J$$$N$+!)(B

cron$B$K$h$jDj4|E*$K!"(B

$B!&%F%9%HMQ$N(BHTTP$B%a%C%;!<%8$KEz$($k$+$I$&$+(B
$B!&%5!<%P%W%m%;%9$,5/F0$7$F$$$k$+$I$&$+(B
$B!&%W%m%;%9%a%b%j$O0n$l$F$$$J$$$+(B
$B!&%W%m%;%9$N(BCPU$B@jM-N($O>e$,$j2a$.$F$$$J$$$+(B
$B!&%G%#%9%/$N6u$-$O$"$k$+(B
$B!&%G!<%?MQ%G%#%l%/%H%j$J$I$,=q$-9~$_$,2DG=$+(B

$B0J>e$N%A%'%C%/9`L\$N8!::$r<+F02=$G$-$k!#(B
$B$b$7>c32H/@8$r8!CN$7$?>l9g$K$O!"(B
$B<RFb(Bsendmail$B$r7PM3$7!"(B
$BEE;R%a!<%k$K$h$C$F<R30$N%5%]!<%HC4Ev<T$KDLCN$9$k$h$&$K(B
$B@_Dj$9$k$3$H$b2DG=!#(B

