??????????????? ???????(IP????)

1
??????????????????????(IP????)
2
???????????????OSI

• OSI?7??????????????5???????
• ???web??????

3
???1(???)
4
???1

• ????10BaseT?????

5
???2
6
???2

• ???2?LAN?????????????????

7
???3(???????)

• ???3????????????

8
???3

• ???3????2????,???2????1?????

9
???4(????????)

• ??????????,??????????????????

10
???4

• TCP?UDP

11
???5(????????)

• ???????????????

12
??????????
13
???????(IP?)???

• ?3?(???????)???
• ???????????????????????????
• ?????????????????????????????
• ????????IP??????
• IP??????

14
IP????

• IP?????1??????
• ???????????????????????,????????????
• IP?????2????
• ??????????????????

15
IP??????(IPv4)

• IP??????????????????????
• ???????????????????????
• 32??????(2324,294,967,296?????)
• ???????????????
• 8?????????10???????????????????

11000000 10101000 10100111 11110111
192.168.167.247
?40?
16
IP?????????????

• IP?????????????????????
• ??????????????
• ????????????????
• ????????????????????

???? 8bit
??????? 24bit
17
IP????(????NW?????)

• ???????????????????????
• ?????????NW????
• NW??(????)????3??NW-ID????
• ?????????

126????????,0.0.0.0???,127.0.0.0?????????? 256256
256-216,777,214?????
Class A (1.0.0.0 126.0.0.0)
?????0???????????????,?1??????????????????????????
????????????????????????2??
??????????
0 Network ID Host ID
(191-127)25616,384???????? 256256-265,534?????
Class B (128.0.0.0 191.255.0.0)
1 0 Network ID Host ID
(223-191)2562562,097,152???????? 256-2254?????
Class C (192.0.0.0 223.255.255.0)
1 1 0 Network ID Host ID
?1?????
?2?????
?3?????
?4?????
?1????????????????
18
????????

• ?????????NW?????????????????????NW???????????????
  ??
• ?????????????NW????????????

???B?Network ????
???B?Host ????
10000001 10101000 10100111 11110111 11111111
11111111 11111100 00000000 10000001 10101000
10100100 00000000
129.168.167.247 255.255.252.0 129.168.164.0
AND
Subnet address
Host part
Network part
Subnet part
Subnet mask
??????????????
19
?????????????
10000001 10101000 10100111 11110111 11111111
11111111 11111100 00000000 10000001 10101000
10100100 00000000
129.168.167.247 255.255.252.0 129.168.164.0
??? IP????
????? ???
?????? (??)???????
??????????????????129.168.164.0????. ????,????????
????????????????????,?????????all0??all1??????
?????
10000001 10101000 10100100 00000000
(129.168.164.0)
10000001 10101000 10100111 11111111
(129.168.167.255)
???,129.168.164.0????????????,129.168.167.255????(
????????????)??????????????
20
CIDR(??????????????)

• 1991-CIDR(Classless Inter-Domain Routing)
• ?????????????B?????????????.
• ???C???????,?????.
• ???(??????????)???.
• ?????????
• ?????????????,???????????????(???)????.
• prefixIP????/????????
• 192.32.1.0 255.255.255.0 ltgt192.32.1.0/24
• 192.32.0.0 255.255.0.0 ltgt192.32.0.0/16
• ???????,
• ???????129.168.164.0?,??????255.255.252.0????????,
  ??? 129.168.164.0/22?????.
• ??????????????????????????

21
CIDR???????
201.23.1.0 201.23.2.0 201.23.3.0 201.24.1.0
23 00010111 24 00011000 16 00010000
201.16.0.0/12
201.23.1.0 201.23.2.0 201.23.3.0
201.24.1.0
201.23.0.0/16
201.24.0.0/16
201.23.1.0
201.23.1.0
201.23.2.0
201.23.2.0
201.24.1.0
201.24.1.0
201.23.3.0
201.23.3.0
22
CIDR???????

• 212.56.132.0/24 11010100.00111000.10000100.000000
  00
• 212.56.133.0/24 11010100.00111000.10000101.000000
  00
• 212.56.134.0/24 11010100.00111000.10000110.000000
  00
• 212.56.135.0/24 11010100.00111000.10000111.000000
  00
• ????????????????????????
• ???????????(???????????????)
• 212.56.132.0/22 11010100.00111000.10000100.000000
  00

23
???????????????
????IP???? 212. 62. 31. 90 ???????? 255.255.255
.224 ???,???????????????????????? 11010100
00111110 00011111 010 11010 (212.62.31.90)
11111111 11111111 11111111 111 00000
(255.255.255.224) 11010100 00111110 00011111
010 00000 (212.62.31.64) ? ??????????,212.62.31.
64??? CIDR??????,212.62.31.64/27
??? ??????????????IP?????,?????????all 0 ??all
1?????? 11010100 00111110 00011111 010
00000 (212.62.31.64) ?? 11010100
00111110 00011111 010 11111 (212.62.31.95) 212
.62.31.64 ?? 212.62.31.95???. ????,64???????,95???
????,65??94?30??????????????
24
ICMP (Internet Control Message Protocol)

• ICMP??????????
• IP???????????????????????????
• ????????????????????????????
• ICMP?IP?????????????????,
• ???????
• ??????
• ????????(TTL)?????
• ?????????
• ...
• ??????????
• ping, traceroute ? ICMP???????
• ping?????????????????????
• traceroute?????????????????

25
??????????

• ????PC?
• IP???? 192.168.1.10 (1000001010)
• ???????? 255.255.255.248 (24811111000)
• ????,???????????????????????????,192.168.1.8
  ???(800001000)
• ???
• 192.168.1.12????????????
• ?????????????????????????????????
• 192.168.1.12255.255.255.248192.168.1.8 ?????!
• 1200001100
• 24811111000 ? 000010008

26
????????????

• ????
• 192.168.1.20 ????????????
• ???????????????????????
• 192.168.1.20255.255.255.248192.168.1.16? ????!
• 2000010100
• 24811111000 ? 0001000016
• ??????????????????????
• ???????????????????????????????