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��̋L�^�͖^��w��WWW�T�[�o�� traceroute ��ʂ��̂ł��B ��ǂ�ňȉ��̖�ɓ��B

% traceroute www.keio.ac.jp
traceroute to sh.cc.keio.ac.jp (131.113.1.25): 1-30 hops, 38 byte packets
 1  atm-gw.is.kochi-u.ac.jp (133.97.166.1)  2.56 ms  1.49 ms  1.49 ms
 2  cisco-c2.cc.kochi-u.ac.jp (133.97.8.12)  1.93 ms  1.74 ms  1.78 ms
 3  csi-kochi.cc.kochi-u.ac.jp (133.97.1.2)  2.61 ms  2.71 ms  2.20 ms
 4  202.15.112.81 (202.15.112.81)  21.3 ms  17.6 ms  23.7 ms
 5  numata-saijo.csi.ad.jp (202.15.112.49)  24.2 ms  14.7 ms  40.4 ms
 6  cisco1.hiroshima.wide.ad.jp (203.178.138.1)  32.6 ms  15.9 ms  14.9 ms
 7  cisco7.nara.wide.ad.jp (203.178.141.69)  354 ms  310 ms  264 ms
 8  cisco8.nara.wide.ad.jp (203.178.137.182)  266 ms  *  342 ms
 9  cisco6.nara.wide.ad.jp (203.178.140.225)  318 ms  *  397 ms
10  cisco2.otemachi.wide.ad.jp (203.178.136.85)  313 ms  *  371 ms
11  cisco12.fujisawa.wide.ad.jp (203.178.141.82)  378 ms  352 ms  *
12  cisco18.fujisawa.wide.ad.jp (203.178.137.87)  436 ms  350 ms  426 ms
13  keio-wide-p2p.sfc.keio.ac.jp (133.27.1.253)  409 ms  393 ms  430 ms
14  fw3.sfc.keio.ac.jp (133.27.1.3)  521 ms  426 ms  *
15  131.113.4.161 (131.113.4.161)  390 ms  452 ms  329 ms
16  icr.cc.keio.ac.jp (131.113.4.169)  244 ms  390 ms  *
17  sh.cc.keio.ac.jp (131.113.1.25)  363 ms  *  438 ms

�ړI�z�X�g�̖{�� IP �A�h��X�𓚂��B
sh.cc.keio.ac.jp (131.113.1.25)
��m��w��O��֐ڑ��Ă��郋�[�^�� IP�A�h��X�𓚂��B
(133.97.1.2)
�ړI�̃z�X�g�܂ł̊Ԃɉ��̃��[�^��邩�B
csi.ad.jp ��
```
s. [�g�pIP�l�b�g���[�N]         202.15.112.0-202.15.115.0
```
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22bit
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```
�ŏ��A�h���X 202.15.112.0   = 11001010.00001111.01110000.00000000
�ő�A�h���X 202.15.115.255 = 11001010.00001111.01110011.11111111
```
��A�z�X�g�� 8+2 = 10bit �l�b�g��[�N�� 32-10 = 22bit
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2¹⁰ - 2 = 1024 - 2 = 1022

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- ��l�b�g��[�N�̒��ŒʐM�� IP�A�h��X��m��Ă��邪�A Ethernet �A�h��X��m��Ȃ��B
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