Title: Questions raised by students ? ?????????
1Questions raised by students? ?????????
- Q_1 I could not take a note of the URL.
- http//www.goto.info.waseda.ac.jp/goto/tokuron.
html - A_1 Do not worry. It is clearly shown in
the syllabus. - ? ??????URL????????
2- Q_2 Why the token-ring network is not used
anymore? - ? ??2??????????LAN????????????????
-
- A_2 It was not widely used because it was more
expensive than Ethernet. - ? ??2 ???????????????????????
3Four (4) FDDI Interface cards?FDDI ?????????? 4?
- JPY 932,400
- USD 11,655 (_at_180yen)
- ? 932,400?
4THE ARPA NETWORKDEC 19694 NODES
940
2 SRI
4 UTAH
3 UCSB
PDP 10
360
1 UCLA
Sigma 7
? 1.1 ARPA???????(1969)?Famous ARPAnet at the
initial stage, 1969
5THE ARPA NETWORK SEPT 1969 1 NODE
1 HOST Sigma 7
1 IMP UCLA
? 1.2 ARPA?????????? The very first
configuration of the ARPAnet in 1969
6??????)???????????????????????????????????????????
??????????????????????????????????????1983????????
????????????????????????????
? http//www.isc.org/solutions/survey
??)??????????????? The original data for the
graph
Date Hosts 08/1981 213 05/1982
235 08/1983 562 10/1984 1,024 10/1985 1,961
02/1986 2,308 11/1986 5,089
? 1.3 ???????????????????? ? The number of
connected hosts in the Internet (Domain Survey)
7? 1.4 ??????????????? The history of the
Internet in the US
- APRAnet
- 1972 ???????????? ? Demonstrated at a conference
- TCP/IP????? ? Converted from NCP to TCP/IP
- ???????? ? Introducing Domain Names
- NSFnet
- 1995 NSFnet???? ? NSFnet stopped
1990 ARPAnet???? ? ARPAnet stopped
vBNS remained Super Computer Centers(5 sites
only)
100
Internet2
- In 1995, US Government stopped their support to
the Internet. - In 1996, US Government resumed their strong
support.
8What are non-trivial technologies in POTS?
Plain Old Telephone Service ? ???? ???
? ??????????????????
9We need four (4) wires for duplex communications.
receiver
transmitter
???
???
transmitter
receiver
???
???
? ? 2.1 ????????4????(?????????????????)
10We need an invention to reduce the number of
wires from four (4) to two (2).
receiver
???
????? ???????
?????? ?????
???
transmitter
Balanced circuit in the telephone set
Impedance of the circuit
? 2.2 2????????
11If you have five (5) subscribers, how many links
we need?
(54)/210
Subscriber A
Complete graph? ?????
? ? 2.3 5?????????
12subscribers
A
B
C
D
E
Crossbar switch
? ? 2.4 ???????
A
B
C
D
E
13incoming
1
1
1
2
2
3
3
2
4
4
3
5
5
outgoing
1
2
3
Notational convention crossbar switch
? ? 2.5 ???????
1420
20
(53)4(44)3(35)4168
(2019)/2190
Combination of small crossbar switches
? ? 2.6 ??????????????
15Traffic theory, ???????
- Call Poisson distribution
- ? ???? ??????
- Holding time negative exponential distribution
- ? ????(????) ??????
16Computer networks used analog telephone lines.
? ? 2.7 JUNET???????????
17dialing
POTS
ENUM
gateway
????
SIP server
DNS
IP??
IP network
IP phone
? ????IP??????????????? ????2002?2?
?5-4
Report by MIC, JP government
http//www.soumu.go.jp/s-news/2002/020222_3.html
Telephone number and enum, ? ? 2.8 ?????ENUM
18Examples of URI (RFC 2396)? ? 2.9 URI??
ftp//ftp.is.co.za/rfc/rfc1808.txtgopher//spinal
tap.micro.umn.edu/00/Weather/California/Los20Ange
les http//www.math.uio.no/faq/compression-faq/pa
rt1.html mailtomduerst_at_ifi.unizh.ch
newscomp.infosystems.www.servers.unix
telnet//melvyl.ucop.edu/
20 means a space ? 20?????(??)?????
19Next Generation Network is real? ? 2.10
?????????(NGN)
New Generation Network
Internet
Public Switched Telephone Network
Mobile phone
20?)????????????????????
6
6
2
461500(???)
2
???MAC???? ????MAC???? ???,Type ???, Data FCS
Source
Destination
???MAC???? ????MAC???? ??????? LLC SNAP ???,Data FCS
6
6
2
3
5
381492(???)
2
Length
?? Terms FCS Frame Check Sequence LLC Logical
Link Control SNAP Sub-Network Access Protocol
There are two (2) Ethernet Frame formats. ? ? 3.1
2??????????????????
21IETF
???
??(1) ?????1-3 ??????????????????? ????????RFC??
?????????1998 ??(2) ?????3-5 ?????MCR? ?????????
????IE??????2000 ??????????????
Other
Internet-Draft (?????)
??????????
Other organizations
approval
Experimental RFC (?????????)
IESG?????
Proposed Standard (??)
Draft Standard (?????)
Informational RFC (???????? ???RFC)
BCP(????????RFC) (Best Current Practice)
Internet Standard (??????????)
Historic RFC (?????RFC)
Standard track (??????)
BCP??
FYI?? For Your Information
STD??
- How to standardize RFCs in IETF? ?3.2
IETF??????????
22?7? ?????????
?6? ??????????
?5? ??????
?4? ????????
?3? ???????
?2? ???????
?1? ???
Application
Presentation
Session
Transport
Network
Data Link
Physical
OSI reference model, 7 layers? ? 3.3 OSI?????
23EthernetHeader
IPHeader
TCPHeader
ApplicationData
EthernetTrailer
?????????? IP???????? TCP???????? ??? ???????FCS
Actual Data Format in Communication Channel ? ?
3.4 ????????????
24???, Application Data
TCP????????,Header TCP????, TCP Data
IP????????,Header IP????, IP Data
??????????, Ethernet Header ??????????, Ethernet Data ???????FCS, Ethernet
Encapsulation of Packets? ? 3.5 ????????????
25Topology of Local Area Network? ? 4.1
LAN???(????)
?Bus ? ??
Bus? (b) ???
lt Omnibus? ?????
Star Shape ? (a) ????
Ring ? (c) ????
26Multiplex, ? ???
- TDM, Time Division Multiplex
- ? ???????
- FDM, Frequency Division Multiplex
- ? ?????????
- CDMA, Code Division Multiple Access
- ? ????????
27Collision, ??
- Token
- ? ??????
- Collision Detection
- ? ????
28Ethernet, ? ??????
- CSMA/CD
- CS, Carrier Sense
- ? ????(???)????
- MS, Multiple Access
- ? ??????
- CD, Collision Detection
- ? ????
Robert MetCalfe
29Ethernet and a coaxial cable (yellow) ? ? 4.2
????????????????
3024 bits24???
24 bits24???
0 0 ? ?????? ? ?????????
OUI, Organizationally Unique ID
Network Interface Controller (NIC) specific
The most significant bit is 0, the address is
individual. If it is 1, the address is used for a
group. ????1?????0 0?????????????????
???0??????1????????????????? If the
second bit is 0, the address is universally
administrated. If it is 1, it means local
administrated address. ?2???1????0
???????????????????
???0??????1???????????????? IEEE assigns an OUI
to an organization. ??????? OUI
(Organizationally Unique Identifier)
IEEE??????? The organization assigns the three
octets, observing the uniqueness ruls. ?????????
??????????????????????
MAC address (IEEE 802) ? ? 4.3 MAC???????
31Is it possible to use MAC address only for the
Internet?? MAC??????????????????????
- Why we need IP addresses while each host machine
can be identified by the MAC address? No answer
is given in this slide. - ? MAC?????????????????????????????IP??????????????
? ?????????????
32Repeater, ?????
One network segment,? ?????????????????
Bridge, ?????
Two separate network segments,? ?????????????????
Repeater and Bridge, ?? 4.4 ?????????
33Decimal, ?10??
172.16.73.108
172
16
73
108
Binary, ?2??
1 0 1 0 1 1 0 0
0 0 0 1 0 0 0 0
0 1 0 0 1 0 0 1
0 1 1 0 1 1 0 0
Network ID? ???????
Host ID? ????
An example, IP address? ? 4.5 IP???????
348 bits? 8???
8 bits? 8???
8 bits? 8???
8 bits? 8???
Class A ????A
0
1 bit, ?1???
Class B? ???B
1 0
2 bits, ?2???
Class C????C
1 1 0
3 bits, ?3???
Address Class (traditional) ? ? 4.6 ????IP????????
35Telephone Numbers in Japan
- Area Code ?????
- Tokyo ?? 03-3203-4141
- Kawaguchi ?? 048-269-7961
- Saga ?? 0955-58-9000
36IP???????? Data, IP payload, ?IP????
header
?IP???????
?????, Ver. ????, length ???????, type (TCS) ?????, total length
(????)
???, identification ???, flag ???????????, offset
(????)
????, TTL ?????, Protocol ?????????, checksum
(????)
???IP????, source IP address
(????)
??IP????, destination IP address
(????)
?????, option ?????, padding
0
31
7
8
15
16
23
24
IP Header ?? 5.1 IP???????????
37A simple network ?? 5.2 ????????????
38Domain Name????? example.goto.waseda.ac.jp IP
addressIP???? 133.9.81.79 MAC
addressMAC???? 00080D435AD8
DNS???
ARP???
Address resolution ?? 5.3 ???????
39RARP request, ??????
RARP reply, ???
Disk ?????
Diskless workstation (D) ???????D???????????????
Workstation (C)???????C?????????
D knows its MAC address, ????MAC???????????D
does not know its IP address, ????IP?????????
IP address 133.9.81.79 MAC address
00080D435AD8
RARP???
Reverse ARP?? 5.4 RARP?????????
40router???
A router has at least two interfaces ?? 5.5
?????????
41Router ????
This slide does not cover the whole story. ?
????????
- ????
- Scholarship and the martial arts
- Be both a good warrior and a good scholar
- Software and hardware
42One may lose money through stock options?
????????????????
- A company gave him a stock option instead of JPY
500,000 cash. - When the exercise term was about to over, the
stock value was JPY 200,000,000. - He had to pay JPY 100,000,000 as an income tax.
- Can you guess how much he earned?
43Ikebukuro
?? ??
Shinjuku
A traffic sign does not give you the global
map. ? ? 5.6 ?????????????????????
44Sugamo
Ikebukuro
Shinjuku
Shibuya
Meguro
Gotanda
??
??
??
??
??
???
???1 Distance 1
??1
??1
??1
??1
Interconnection of multiple routers ?? 5.7
??????????????????
45Sugamo
Ikebukuro
Shinjuku
Shibuya
Meguro
Gotanda
??
??
??
??
??
???
?? 8
?? 1
?? 8
???
?? 1
?? 0
?? 8
11
81
min(81), (11)
2??
?? 8
?? 1
?? 2
?? 1
?? 0
?? 8
21
?? 3
?? 1
?? 2
?? 1
?? 0
?? 8
3??
31
?? 3
?? 1
?? 2
?? 1
?? 0
?? 4
4??
Calculation of the metric ?? 5.8 ?????????????
46Sugamo
Ikebukuro
Shinjuku
Shibuya
Meguro
Gotanda
??
??
??
??
??
???
????
?? 3
?? 1
?? 2
?? 1
?? 0
?? 4
1??
?? 3
?? 8
?? 2
?? 1
?? 0
?? 4
31
81
min(31), (81)
2??
?? 3
?? 8
?? 4
?? 1
?? 0
?? 4
41
3??
?? 5
?? 8
?? 4
?? 1
?? 0
?? 4
41
51
51
?? 5
?? 8
?? 6
?? 1
?? 0
?? 6
4??
Count to the infinity ?? 5.9 ????????
47TCP???????? TCP????, TCP data
TCP header? TCP???????
(????)
????????, Source Port ??????? ,Destination Port
???????(SEQ)
(????)
??????(ACK)
(????)
???????? ???Reserved ?????????, flag ????????, window size
(????)
??????, TCP checksum ??????, Urgent pointer
(????)
?????, Options if any ?????
0
31
7
8
15
16
23
24
TCP header? ? 6.1 TCP????????
48UDP???????? UDP????, UDP data
UDP headerUDP???????
(????)
????????, source port ???????, destination port
?????, UDP length ??????, UDP checksum
0
7
8
23
24
31
15
16
UDP packet header ? ? 6.2 UDP????????
49Waseda University
?????
Relay ???
????
Osaka University
????
Kyushu University
Good Old Days, kind Mail servers? ? 6.3
???????????
50FTP serverFTP???
FTP client FTP??????
21
1202
Notify the port number by a PORT command ?
PORT?????1203???
1203
FTP server FTP???
FTP client FTP??????
21
1202
20
1203
Port numbers of FTP, they use two port numbers?
? 6.4 FTP?????????
51 telnet muse01.mse.waseda.ac.jp Trying
133.9.6.71... Connected to muse01.mse.waseda.ac.jp
. Escape character is ''. Red Hat Linux
release 7.1 (Seawolf) Kernel 2.4.2-2smp on an
i686 login goto Password
Echo of the input?????????????
No echoes for the password?????????????
Old style Telnet starting sequence ? ? 6.5
TELNET?????
521. Selection of the protocol, TCP/IP or DECnet ?
1.????????
Packet???????????????
Uni-directional Or One-way link ???????? ????????
??????
???packet?????
Packet ???????????????
Bi-directional Link ???????? ?????????????? ????
?????
???packet?????
2. Uni-directional link vs. Bi-directional
link ?? 6.6 ??????????????????
53Server???
Client ??????
Client ??????
Client ??????
Super Node ???????
Node ???
Node ???
Node ???
Client and Server model vs. P2P (Peer to Peer) ?
6.7 ??????????P2P???
54Japanese people do not invent a new device. They
improve everything.??????????????
- Remarkably new ideas in the InternetAvenue,
prior to Gopher ???? K. UmemuraDelegate, prior
to Java ??? Y. Sato
55Good responses bring an invention? ????????????
- Why they stopped their projects?????????????
- Poor responses???????
- Good responses?????????????????
56TCP connection, establish and terminate? ? 7.1
????????????
SYN
FIN
SYN, ACK
ACK
time
ACK
time
FIN
? ?????
? ?????
ACK
(a) establishment, 3-way handshake ?(a)
????3-way???????
(b) termination, FIN and ACK? (b) ????FIN?ACK
57TCP packet, ?????
IP header???? TCP header? ??? TCP date, ? ???
IP packet, ?????
TCP packet and IP packet, encapsulation? ? 7.2
TCP??????IP??????????
58Data, ????
Communication link? ????
Sender????
Receiver????
ACK
Data should be copied for re-transmission?
????????????????
The sender waits for the acknowledgement for
2(normal RTT).????????ACK????????????????2?????
It re-transmits the data when there is no ACK.?
ACK????????????????
Resend, ???
Sender? ???
Receiver ????
ACK
Acknowledgement and re-transmission? ? 7.3
ACK??????????
59Sender? ???
Receiver? ???
Data, ????
One-way delay??? 2.5ms (???)
ACK
Round trip time? ?? 5ms (???)
time
? ????
The receiver is located 450km away from the
sender? ? 7.4 ????????450km???????
60Receiver????
Sender? ???
The sender does not wait for the ACK. It
continues to send the data until it reaches the
limitation of the window size. ?
???????ACK???????????????????????????????????????
???
Window control? ? 7.5 ???????
61Data which will be sent, ?????????????
The leftmost data is sent first, ???????????
ACK
ACK
Data????
Sent????
Sent and ACK received????ACK???
Sliding window, ?? 7.6 ??????????
62A simple exampleFrom Tokyo to Kansai
450km?????450km
Data, ????
ACK
(450/180)25ms
63How much we can send???????????
- 64bit5ms 12.8Kbps
- 512bit5ms102.4Kbps
- 64Kbit5ms 12.8Mbps
- 512Kbit5ms102.4Mbps
Window size cannot be infinite.? ?????????
64Regardless of the speed of the fiber?
?????????????
- 64KBytes
- ACK
- 64K 8 bits / 5msec 102.4 Mbps
65From Tokyo to Singapore? ????????
- Distance 5940km, delay time 33ms (one-way)
- Window size 64KBytes
- Throughput 7.76Mbps
- Data communication is slow,While the Fiber link
offers a high speed. - ????????????,????????
- (2.4Gbps, 10Gbps, 100, 200...)
6610Gbps
throughput
? ??????
RTT, Round Trip Time, ? ??????
Speed of the link, ????????
155Mbps
Slope???
W
RTT
Speed of the link, ????????
13Mbps
Speed of the link, ????????
Window size, ??????????(W)
Limitation of the throughput, ? ? 7.7 ?????????
67Why the window size is small???????????????
688. Management and Operation? ????????????
- The Internet was operated by volunteers.Now, the
most traffic is carried by commercial ISP.?
??????????????????? ????????????????????? - It was in a state of anarchy.In reality, there
is an established order.? ???????????????????
??????????????????? - NIC and NOC? ???????? NIC and NOC
69NIC, Network Information Center
- JPNIC in Japan, APNIC in Asia Pacific?
????JPNIC, ???????APNIC - IP addresses, and AS numbers? IP?????AS??
- How about domain names? JPRS in Japan?
??????????JPRS (JPNIC??) - History of JPNIC1984 Junet-admin, 1991 JNIC,
1997 JPNIC? JPNIC???
70JPNIC
- JPNIC web page, www.nic.ad.jp? JPNIC?web???
- JPJapan (ISO country code)UK did not follow ISO
code which is GB.? ccTLD?ISO????????????? - www.waseda.ac.jpWWW.WASEDA.AC.JP
- Internationalize domain names (IDN)???.jp
????.jp
71JP domain names
- JPRS, http//jprs.jp/info/jp-dom/
Generic, ? ??JP????? ?EXAMPLE.jp
?????????.jp Attribute, ? ???JP?????
?EXAMPLE.co.jp Geographical, ? ???JP?????
?EXAMPLE.chiyoda.tokyo.jp
72NOC, Network Operation Center
- MNC, Media Network CenterIT Center, Waseda
University? ???????MNC,IT??????? - Monitoring? ???????????
- It is important to know the normal state
statistics.? ??????????????? - Trouble ticket? ????????(?????)
73Trouble shooting ? ????
Machine for Analysis ? ???????
Capturing packets ? ???????
Communications ? ??
Network Analyzer, or Sniffer ? ? 8.1 ????????????
74Number, Address, Port, Address, Port, Protocol,
Summary, Length, Time, Delta, Time stamp
http//www.asteceyes.com/
GUI Interface of Analyzer ? ? 8.2
??????????????????
75SNMP Agents devices Which responds to SNMP
protocol? SNMP?????????? ???(SNMP??????)
SNMP Managerworkstation? SNMP??????(?????)????
????????
Computers ? ??????
Routers ? ???
Switches ?????
Devices report the value of counters etc. to
the manager ? MIB II ??????????? ????????????
SNMP, Simple Network Management Protocol? ? 8.3
SNMP??????????????
76Trouble Shooting (1)
- Slow speed ? ???????
- Saturated bandwidth, pathchar? ??????????
- Traffic congestion, TCP retransmission ?
??(???????)?TCP??? - Heavy load routers? ?????????????
- Disconnected ? ????????
77Trouble shooting (2)
- Cannot connect ? ??????
- DNS, PTR record? DNS????????????
- Routing loop ? ?????????
- Software, e.g. acking ack? ?????????, acking ack
- Human error, mis-configuration? ?????????????
- Physical problems, electric power, fiber cut?
????????????????????
78Routing Loop ? ? 8.4 ??????
79Security issues ??????????
- Malware, malicious software? ??????????????
- Incident response JPCERT/CC, IPA? ?????????
JPCERT, IPA - Virus and vacctine? ?????????
- Security hole, stepping stone? ?????? ???????
- Buffer overflow attack? ????????????????
80? 9.1 ??????????????
?ISP
?ISP
?ISP
POP
????
????
????
??????
??????
POP (Point of Presence)
POP
POP
??????
??LAN
?? (???????)
ADSL
FTTH
???
????
?????
?????
81? 9.2 Single Star???Double Star??
SS Single Star ?? ?????? ????????? ??
DS Double Star ?? (PON??) B-PON?G-PON, E-PON
????
OLT
OLT
OLT
????
????
82? 9.3 ????(POP)?????????
??????
R
R
?????? ?????
R
R
???? (POP)
SW
SW
??????
R
R
R
R
????????
?????
?????
83? 9.4 ??????
???????
???????
???? (POP)
???? (POP)
??????
???
???
???
?? ??????
?? ??????
???
???????????? ?????????
?????????????? ?????????
84? 9.5 ?????????
??
??
R
R
????
????
R
R
????
????
???
R
R
????
????
R
R
????
????
???
???? (POP)??
???? (POP)??
??????????????POS????????? (POS Packet over
SONET/SDH)
85? 9.6 ????????????
?????? Transit
????? Peering
?????????
?????X
?????Y
?????
?????X??????Y???????????????????
??????????????X?????????????????????????
?????X
86? 9.7 ????????
???????????
(?????)????? ???2
(?????)????? ???3
?????
?????
?????
?????
?????
?????
SW
R
?????
?????
?????
?????
?????
?????
BGP??
??????????? ?Layer2? (?????)????? ?Layer2? (?????)????? ?Layer3?
?? ???????????????????????? L2?????????????LAN????????(BGP???) L3???????????????????????????????
?? ??????????????? ??????????????? ????????????????1???????
?? ??????????????????????????? ??????????????????? ?????????????????????????????
87? 9.8 ?????????????????????????
?????A
?????B
?????X
?????Y
??
??
88? 9.9 ??????????
??
??
R
R
????
????
R
R
???? ??? ??
????
????
?????
?????
??????????? ??????? ??? ???????????? ???????????
?? ??????????????
89? 9.10 ????????????????(OSPF)
??
??
??
100
100
R
R
R
40
30
20
R
R
R
100
100
(1)
(2)
(3)
(1) 40 100 100 140 (2) 100 30 100
130 (3) 100 100 20 120 ? ????
??-???????????
??
??
??
100
100
R
R
R
40
30
20
R
R
R
100
100
(1)
(2)
(1) 40 100 100 140 (2) 100 30 100
130 ? ????
90? 9.11 ????(POP)?????
??????
R
R
?????? ?????
R
R
???? (POP)
?????????????????????OSPF?????? ??????????????????
??
SW
SW
??????
R
R
R
R
????????
?????
?????
91? 9.12 ????????
???
?????????
???????????? ?????????
?????-1
?????-2
?????-3
?????A
?????B
IX
?????C
IX
???
92? 9.13 ????????????????
??????????????? ????????????????
????????????????(??)
??????????????? ?????????????????????????
????????????????(??)
93? 9.14 ?????????????
??
??
?????
??????? ?????? (???????)
??(??? ??)??? ????
IX??????
??(?????) ???????
?????? (?????????) (?????)
??? ?????
94? 9.15 ????????
?????????
?????A
?????B
??????? ??????
?????D
?????E
?????C
95? 9.16 ???????
????????? ?????C??????E?????????????????? ????????
????????
?????A
?????B
?????D
?????E
?????C
????? IX
???????? ?????C??????E????????????????
96? 9.17 ????????????(95??)
????
??
??????????????
????
????? ????? ????
95
5
97? 9.18 ?????
????? ???
???????
?????-A
?????-B
??????
???????? ??????????
?????-X
?????-Y
98? 9.1 ???????????
???? POP ?????? ????
??? (????) ??????????? (????) ?????? ??????2???????? ?????????????? ???????????? ????????(???????????) ??????????????? ??IX???(?????
??? (????) ???????? (????) ?????????????????????? POP?LAN???? ????(BGP?OSPF????) ????(BGP?OSPF)???? ????(BGP)?????
99? 10.1 ???????? (1)?????????????????
???????
???
???
????????????????????????????????????????
100? 10.2 ???????? (2)???????????????
SYN
SYN
???????
SYN
SYN
SYN
SYN
SYN
SYN
SYN
SYN
SYN
SYN
SYN
SYN
SYN
SYN
???
SYN
SYN
SYN
SYN
??????????????????????????????????????????
101? 10.3 Botnet???
SPAM?????
??
DDoS??
????
?? (Herder)
???????? ????
?????? (IRC??)
???PC (????PC)
102? 10.4 spam???????????
??? ?????
?????
???????
SPAM???
????????????????????
?????
103? 10.5 ??????????? DKIM (Domain keys Identified
Mail)
(3) ??????????????DNS????????????????????????
(2) ?????????????????????????????????????????????
????????
???? ????????? ?????
????????
example1.co.jp
example2.co.jp
DNS??? (example1.co.jp)
(1) ???????????????DNS???????
104? 10.6 OP25B, Outbound Port 25 Blocking??????????
???? ?????
????????????????????
??? ?????
?????
25
25
25
?????
25
SPAM???
?????
?????
SMTP(TCP/25)?????????????????
105? 10.7 OP25B, Outbound Port 25 Blocking)
?????????????? ?????
???????????????????25???????(?????????????????????
)
??????25?????????? Submission port
(587)????????SMTP????????????
??? ?????
?????
25
25
587
25
?????
25
SPAM???
?????
?????
??IP????????????????????????TCP25(SMTP)???????? ??
????????IP???????25???????????
106? 10.8 SYN Flood??
???
???
SYN
(1) ????????????????TCP SYN???????????
(2) TCP????(???????)??????????
????
????
(3) ??????????????????????? ??????????????????????
?????
(4) ??????????(?????)?????????????
107? 10.9 Smurfing??
PC
PC
PC
R
PC
PC
PC
R
PC
PC
???????????IP???????? ????????????????ICMP??????
R
PC
1??ICMP echo request ????????ICMP echo request
?????????????????
108? 10.10 DNS???? (DNS Amp Attack)
DNS ?? ???
??
DNS ????? ???
??????????????????????
??
?
??
???
DNS ????? ???
?
??
??
?
?
????
??
?
?
??
DNS ????? ???
???????????IP???????? ???????DNS???????????? (??
?????????????????????????????????)
???????DNS?????????????????DNS???????????????????
???????
109? 10.11 ???????????
?????? ??????
???? ??????
R
R
R
R
????????
????????
110? 10.12 ????????????????????????
?????? ??????
???? ??????
R
R
??
R
??
R
??
???????????????????????????
?????????
111? 10.13 ?????????????????????
?????? ??????
???? ??????
R
R
R
R
????
??????????????????????????
??????????????????????????? ?????????????????????
?????????
112? 10.14 ????????
???????
??????????
?????
????????
??
???????????????NW??????????????????
113? 10.15 ???????????
DMZ
DNS ???
?????????DMZ??DNS?????Web???????? ??????????DMZ???
???????
????DMZ???DNS?????Web???? ????????
???? ??????
???? Web???
DNS Cache ???
??
????????
????????
??????????????????????????
????????????????Web??????????????????????
114? 11.1 Lipsey???24?????
- 1.????? 90008000 BC
2.?????? 85007500 BC 3.?????
80007000 BC 4.??
40003000 BC 5.??
34003200 BC 4.??
2800 BC 7.?
1200 BC 8.??
????
?????????????(476)?????????
115(??)
- 9.3??????? 15th ??
10.?? 16th ??
11.???? 18th ???19th ????
12.?? 18th ???19th ???? 13.??
19th ???? 14.???? 19th
???? 15.???? 19th ?????
16.?? 19th ????
116(??)
- 17.??? 20??
- 18.??? 20??
- 19.???? 20??
- 20.?????? 20??
- 21.Lean production 20??
- 22.??????? 20??
- 23.????????? 20??
- 24.???????? 21??(??)