Preda Vanja

5/27/2018 Preda Vanja

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?


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?

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( )

(, ,

, , ...)

( )

,

( )

, ,

5


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, , Skype, Messinger

,

,

6


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(LAN)

Ethernet

( )

7


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( )

( )

(

)

?

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( )

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11


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12

M

? .

, () .


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(

)

,

13


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15


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:

, ,

.

,

16


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?

?

,

(CRC, Sumcheck) 17


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( )

*

...)

(

...) 18


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19

?

, .

--


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--

,

?

?

20


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De facto ( RFC)

De jure ( ISO)

21


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22


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23

Step 1:

Step 2:

Step 3:

::::::::::

1:

2:

3:

::::::::::

1:

2:

3:

::::::::::

( )


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?

,

24


25/467

25

(padding)

.


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(, ,

, ,

)

LAN

(, ,

).

26


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,

,

Token-ring FDDI

27


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28

--

Frame relay


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29


30/467

(.)

B ursty ()

symmetric ()

D elicate ()

30


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(.)

31


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(

) (

)

32


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()

()

33


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34

1

2

3

(router)


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35

Buffering (queues)


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:

36

A

B


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37

:

4

= 9600 bps

= 5000bits

, Tp= 1 ms

Tcs= 1 s

= 1024 bits

.= 24 bits

,

= + +

Tc = 1 + 5000/9600 + 4 0.001 = 1.53 s

= 5000/(1024 24) = 5

= +

+ Tp = 5 (1024/9600) + (4 1)(1024/9600) + 4

0.01 = 0.857


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1

2


39/467

2

ISO OSI TCP/IP

(NIC)

(hub) (switch)

(router)


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3


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?

( )?

()

TCP/IP

( )?

() ()

?

? ? 4


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5

(router) (workstation)

(server) (mobile)


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(,

, , , ....)

()

()

( )

( )

6


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7

1:

2:

3:

::::::::::

1:

2:

3:::::::::::

1:2:

3:

::::::::::


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1969

ARPANET (Advanced Research Project Agency

Network)

,

1970

,

*

) 8


46/467

(.)

1984 TCP/IP

,

,

19891993

1995

9


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( )

?

, ,

10


48/467

IABInternet rchitecture Board

IETFInternet Engineering Task Force

IRTF- Internet Research Task Force ISOCInternet society

IANAInternet Asigned Number Authority

ICANNInternet Corporation for AssignedNames and Numbers

IGFInternet Governence Forum

11


49/467

Internet Service Providers (ISP)

naInternet

POP (Point-of-

presence) ISP

12

NAP (Network Access Point) O (router switch)

ISP

)


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1987 .

NAP

13


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,

RFC (Request For Comments)

FYI (For Your Informaion)

RFC

14


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?

Best effort

(QoS, Quality of Service)

15


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16


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.... 17


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18


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19


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SNA (System

Network Architecture) IBM, DecNet Digital

OSI (Open System Interconnection) TCP/IP

20


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OSI

TCP/IP

TCP/IP

TCP/IP

21


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SI

22

Application

Presentation

Session

Transport

Network

Data Link

Physical

Network

Data Link

Physical

Intermediate System

End

System

Application

Presentation

Session

Transport

Network

Data Link

Physical

R


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SI

23

Application

Presentation

Session

Transport

Network

Data Link

Physical

(FTP, WWW,

, e-, ....).

,

.

(,

)

,

,

.

,


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peer-to-peer

peer-to-peer

24


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25


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26

5

4

3

2

BITS

H2 DATA UNIT T2

DATA UNIT

H4 DATA UNIT

H5 DATA

H3

DATA

5

4

3

2


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27

frame

packet


65/467

TCP/IP

de facto

OSI

28


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TCP/IP OSI

29

Transport

Network

Application

Physical

SMTP FTP

TELNET DNS

HTTPApplication

Presentation

Session

TransportTCP UDP

NetworkIGMPICMP

IP

DHCPARP

Data Link

Physical

Protocols defined by the

underlying networks


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30


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(Repeater)

(Hub)

(MAC )

(Bridge) (Switch)

31

(Router)

Gateway


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(NIC)

()

6 (48

)

(11-2-34-0-23-47)

32


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33


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,

34


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(Bridge)

35

Bridge

A B C D E F


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(Switch)

36

Switch


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( )

?

37


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Spanning tree protocol 38

B1

B2

1

1

3

2

2 3 4

4

B1

B2

Network abstracted into a graph

Each LAN and each bridge represent

a node in the graph


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Cut-through

store-and-forward

store-and-forward

cut-

through

39


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(router)

( plug-and-play)

40


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41

hubs Bridges Routers Ethernetswitches

Traffic isolation no yes yes yes

Plug-and-play yes yes no yes

Optimal routing no no yes no

Cut-through yes no no yes

DevicesProperties

( )


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(e )

: (bridges)

(switches) .

.

IP .

42

?


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?

3000

1000 Hz.

( )

.

43


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1

3


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IP

, ,

VLSM

CIDR

2


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(? ?)

()

( ?) 3


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(interface)

IPv4

4 (32 )

4

1000111110000000 1000100110010000

1st

Byte

= 128

2nd

Byte

= 143

3rd

Byte

= 137

4th

Byte

= 144

128.143.137.144


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IP ?

IP

5


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6

R1

R3

R2

H1

H5H4

H2 H3 H7H6

Network1 (Ethernet) Network3 (Ethernet)

Network2(FDDI)

Network4 (point-to-point)

( )


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(.)

7

Application layer protocol

Transport layer protocol

IP

protocol

Ethernet

protocol

App.

Transp.

Network

Eth.

IP

protocol

FDDI

protocol

IP

Eth. FDDI

IP

FDDI PPP

IP

PPP Eth.

IP

protocol

App.

Transp.

Network

Eth.

PPP

protocolEthernet

protocol

IP

protocol

H1 H6

R1 R2 R3

Network1(Ethernet)Network2(FDDI) Network4(point-to-point)

Network3 (Ethernet

IP


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8

IP

32

232= 4.292.967.296

IP

IP

()

IP


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9

2 23 34 4

5 56 27 38 3

1


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()

10

1.1

3.1

1.21.3

2.1

3

2

3.2

2.2

3.3

1Destination Next hop

1.2 1.21.3 1.32.* 2.13.* 3.1

1.1

Destination Next hop* 1.1

1.2

IP


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IP

IP

( , ,

)

( , , )

( )

11

Network ID Host ID

0 31

IP


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IP

IP

Multihomed host (

)

( ),

12

IP


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IP

IANA (Internet Assigned Number Authority) ICANN (The Internet Coorporation for Assigned Names and Numbers)

RIPE -

ARIN

13


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( )

32 ,

14


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15

IP 193.5.1.5 255.255.255.0

255.255.255.0

24 8 .

24

193.5.1.5/24

Network ID = 193.5.1 Host ID = 5

0 3124


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( 1980.)

5

( 8 , 255.0.0.0)

( 16 , 255.255.0.0)

( 24 ,

255.255.255.0)

, D ( )

( )

16


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1980

( )

,

,

17


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,

:IP 0

B:IP 10 C:IP 110

D: IP 1110

E:IP 11110

18


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19

Net ID Host ID

C

D

E 0

0

0

0 1 2 3 4 8 16 24 31

Net ID Host IDA 0

Net ID Host IDB 01

1 1

1 1 1

1 1 1 1


100/467

,

(193.4.5.0)

,

(0.0.0.3)

, (193.4.5.255)

,

20


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(loopback)

127.0.0.0127.255.255.255 ( )

127.0.0.1

255.255.255.255

21


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22

0

0 hostId

1netId

127

1

0

0 netId


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23

192.16.5.0 192.16.5.3

192.16.5.2192.16.5.1

192.16.4.3

192.16.4.2192.16.4.1

192.16.4.0

192.16.3.0

192.16.3.3192.16.3.2192.16.3.1 192.16.3.4 192.16.3.5

192.16.4.255

192.16.3.255

IP


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24

IP

RFC 1918

(

()

10.0.0.0. - 10.255.255.255 ( A )

172.16.0.0172.31.255.255 (16 B )

192.168.0.0192.168.255.255 (256 C )

A


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25

A: 0 7-

127 (0111111)

( )

: 272 = 126 ,

125

: 2242 =

16.777.214 0 1

B C


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26

B C

B: , 10 128-191

: 214 = 16.384 21416 =16.368

: 2162 = 65.534

C: , 110 192-223

: 221= 2.097.152 or 221256 =2.096.896

:282= 254


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27

1980- 1990-

( )

1990- ( )


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28

C

B

,

( )


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29


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30

IP IP 5

IP 6

(DHCP, NAT)


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31

ISP

B

2

1

?


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32

?

, ,

C

B


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33

B 01

B 01

B:

B :

Network ID

Network ID Host ID

Host ID

Subnet ID


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34

C 11

C 11

C:

:

Network prefix

Extended Network Prefix

Host

suffix

Host suffix

Subnet

0

0

Network prefix


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35

()


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36

R1

R2

130.194.1.0

130.194.2.0

130.194.1.5

130.194.2.5

Global

Internet

All traffic to130.194.0.0

I have only130.194.0.0


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37

(N)

(b), N = 2b

n,

216-b

-2 ako 28-b-2

( )


118/467

(.)

16+b

24+b

,

38


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5 B, 138.10.0.0

3 23= 8 < 5

, 16-3 = 13.

2132

= 8190 .

39

138 10 0 0


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40

Subnet ID First host Last host Broadcast address

32.0 32.1 63.254 63.255

64.0 64.1 95.254 95.255

96.0 96.1 127.254 127.255

128.0 128.1 159.254 159.255

160.0 160.1 191.254 191.255

192.0 192.1 223.254 223.255

138.10.0.0

Subnet 0.0 and 224.0 are avoided. The mask for all subnets is 255.255.224.0


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41

Subnet ID First host Last host Broadcast address

0.64 0.65 0.126 0.127

0.128 0.129 0.190 0.191

0.192 0.193 0.254 0.255

1.0 1.1 1.62 1.64

255.128 255.129 255.190 255.191

The subnet mask for all subnets is 255.255.255.192

140.25.0.0 510


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42

VLSM (Variable LengthSubnet Mask)

?


123/467

, b ( )

43

VLSM


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44

0 255


125/467

45

()

,


126/467

46

Class C24-bit prefix

11000000192 168 64 0/24

10101000 01000000

Class C next24-bit prefix

11000000

192 168 65 0/24

10101000 01000001 00000000

Prefix Host part

00000000

Commonprefix: 23 bits 11111111 11111111 11111110 000000000 00000000

00000000

Classless23-bit prefix 11000000

192 168 64 0/23

10101000 01000000 000000000 00000000

201 10 0 0

8


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47

1100 1001 . 0000 1010 . 0000 0000 . 0000 0000

1100 1001 . 0000 1010 . 0000 0111 . 1111 1111201 10 7 255

21 11

2048

addresses

201.10.0.0 / 21 =

201.10.0.0 201.10.0.255201.10.1.0 201.10.1.255201.10.2.0 201.10.2.255201.10.3.0 201.10.3.255201.10.4.0 201.10.4.255201.10.5.0 201.10.5.255201.10.6.0 201.10.6.255201.10.7.0 201.10.7.255

256 addresses = 1 class C network

EightClass CNetworks= 256 X 8

= 2048addresses


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48

Multiregional 192.0.0.0 - 193.255.255.255Europe 194.0.0.0 - 195.255.255.255Others 196.0.0.0 - 197.255.255.255

North America 198.0.0.0 - 199.255.255.255Central & South America 200.0.0.0 - 201.255.255.255Pacific Rim 202.0.0.0 - 203.255.255.255Reserved 204.0.0.0 - 207.255.255.255

ICCAN


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49

ICCAN


130/467

50

Classless Inter Domain RoutingCIDR(pronounced cider)

,

( )

CIDR


131/467

51

(ISP)

( )

()


132/467

52

,

, , .

192.16.128.0/17192.16.0.0/18

192.16.64.0/18

192.16.0.0/16

CIDR


133/467

53

Internet Service Provider 1

(198.0.0.0 - 198.255.255.0)

NAP

Internet ServiceProvider 2(198.32.0.0-

198.32.255.0)

Internet ServiceProvider 3

(198.33.0.0 -198.33.255.0)


(198.32.0.0/16)


(198.33.0.0/16)

198.32.1.0

198.32.2.0

198.32.3.0

198.33.1.0

198.33.1.0198.32.1.0198.32.2.0198.32.3.0

198.32.1.0198.32.2.0198.32.3.0198.33.1.0

Internet Service Provider 1(198.0.0.0/8)

198.33.1.0198.32.3.0

198.32.2.0

198.32.1.0

198.33.0.0/16198.32.0.0/16

198.0.0.0/8

198.32.1.0


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54

Prefix Mask Prefix Mask

Decimal Binary

128 1000 0000192 1100 0000224 1110 0000240 1111 0000248 1111 1000252 1111 1100

254 1111 1110255 1111 1111

/1 128.0.0.0/2 192.0.0.0/3 224.0.0.0/4 240.0.0.0/5 248.0.0.0/6 252.0.0.0

/7 254.0.0.0/8 255.0.0.0/9 255.128.0.0/10 255.192.0.0/11 255.224.0.0/12 255.240.0.0

/13 255.248.0.0/14 255.252.0.0/15 255.254.0.0/16 255.255.0.0

/17 255.255.128.0/18 255.255.192.0/19 255.255.224.0/20 255.255.240.0/21 255.255.248.0/22 255.255.252.0

/23 255.255.254.0/24 255.255.255.0/25 255.255.255.128/26 255.255.255.192/27 255.255.255.224/28 255.255.255.240

/29 255.255.255.248/30 255.255.255.252/31 255.255.255.254/32 255.255.255.255


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56

()

B11

B15

B14

B16

B12

B13


136/467

57

:

? ?

( )

?

?


137/467

58

20- , 172.16.0.0/20 . 400 , 10 100 , 12 45

6 2 . -- . .

?2(32-20)= 212= 4096


138/467

59

. 400 . 400 2 512. 512 9 29= 512. 20 ID na 3 (20+3+9=32). 400 .

2 3 4 5 6 7 81

-

-


139/467

60

.

100 . 100 2 128 (27= 128).

7 .

512

4 128 .

25 (25+7=32). 512 12 128.

10.

2 3 4 5 6 7 81


140/467

61

128

.

45 6 26=64.

512 ,

5

.


141/467

62

512

8 64 .

26 , 3

.

12 6

5. ,

5

, 6. .


142/467

63

WAN

.

30 . 26 ,

16 .

2 3 4 5 6 7 81 5


143/467

64

Subnet Mask First host Last host

172.16.2.0 255.255.254.0 172.16.2.1 172.16.3.254

172.16.4.0 255.255.255.128 172.16.4.1 172.16.4.126

172.16.4.128 255.255.255.128 172.16.4.129 172.16.4.254

172.16.5.0 255.255.255.128 172.16.5.1 172.16.5.126

172.16.5.128 255.255.255.128 172.16.5.129 172.16.5.254172.16.6.0 255.255.255.128 172.16.6.1 172.16.6.126

172.16.6.128 255.255.255.128 172.16.6.129 172.16.6.254

172.16.7.0 255.255.255.128 172.16.7.1 172.16.7.126

172.16.7.128 255.255.255.128 172.16.7.129 172.16.7.254

172.16.8.0 255.255.255.128 172.16.8.1 172.16.8.126

172.16.8.128 255.255.255.128 172.16.8.129 172.16.8.254



144/467

65


172.16.10.0 255.255.255.192 172.16.10.1 172.16.10.62

172.16.10.64 255.255.255.192 172.16.10.65 172.16.10.126

172.16.10.128 255.255.255.192 172.16.10.129 172.16.10.190

172.16.10.192 255.255.255.192 172.16.10.193 172.16.10.252

172.16.11.0 255.255.255.192 172.16.11.1 172.16.11.62

172.16.11.64 255.255.255.192 172.16.11.65 172.16.11.126

172.16.11.128 255.255.255.192 172.16.11.129 172.16.11.190

172.16.11.192 255.255.255.192 172.16.11.193 172.16.11.252

172.16.12.0 255.255.255.192 172.16.12.1 172.16.12.62

172.16.12.64 255.255.255.192 172.16.12.65 172.16.12.126172.16.12.128 255.255.255.192 172.16.12.129 172.16.12.190

172.16.12.191 255.255.255.192 172.16.12.193 172.16.12.254


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66

Subnet number Mask First host Last host

172.16.14.0 255.255.255.254 172.16.14.1 172.16.14.2172.16.14.4 255.255.255.254 172.16.14.5 172.16.14.6

172.16.14.8 255.255.255.254 172.16.14.9 172.16.14.10

172.16.14.12 255.255.255.254 172.16.14.13 172.16.14.14

172.16.14.16 255.255.255.254 172.16.14.17 172.16.11.18172.16.14.20 255.255.255.254 172.16.14.21 172.16.11.22


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67

202.12.28.0/25

128 hosts

202.12.28.128/26

64 hosts

202.12.28.192/26

64 hosts

202.12.28.128/25

128 hosts

202.12.28.0/24

256 hosts

202.12.29.0/24

256 hosts

202.12.28.0/23

512 hosts

202.12.30.0/24

256 hosts

202.12.31.0/25

128 hosts

202.12.31.128/25

128 hosts

202.12.31.0/24

256 hosts

202.12.28.30/23

512 hosts

202.12.28.0/22

1024 hosts

202.12.28.0/22. 7 , 2

254 , 126 62 .

.


147/467

IP, ICMP, IGMP 1

4

(IPv4),ICMP, IGMP

4


148/467

IP, ICMP, IGMP 2

4

TTL (Time To Live)

ICMP

IGMP


149/467

4 (IPv4)

IP, ICMP, IGMP 3

IP

(.)


150/467

IP, ICMP, IGMP 5

( )

( )

Connectionless

Best effort

IP


151/467

IP

IP connectionless data delivery

UDP(User Datagram Protocol)

(Transmission Control Protocol) connection-oriented data delivery

IP, ICMP, IGMP 6

IP ()


152/467

IP

IP

IP, ICMP, IGMP 7

IP , 4


153/467

(4 )

4 4

(4 )

32- 5(

20 )

15 (

60 ) (8 )

IP, ICMP, IGMP 8

IP (.)


154/467

(16 )

(16 )

(3 )

(13 )

L (Time To Live) (8 )

IP, ICMP, IGMP 9

IP (.)


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(8 )

(1=ICMP, 2=IGMP, 6=TCP, 17=UDP)

(16 ) IP (32 )

IP (32 )

IP, ICMP, IGMP 10

IPv4


156/467

IP, ICMP, IGMP 11

0 3115 16

Source IP address

length

checksum

Destination IP address

version h -length type of service

flagsIdentification Fragmentation offset

time to live protocol

options padding


157/467

IP

IP, ICMP, IGMP 12


158/467

IP, ICMP, IGMP 13


159/467

IP, ICMP, IGMP 14

Precedence Definition

0 routine (normal)

1 priority

2 immediate

3 flash

4 flash override

5 critical

6 internetwork control

7 network control


160/467

IP, ICMP, IGMP 15

Value Service Description AP using the suggested value

0 normal normal datagram ICMP error messages, DNS TCP

1 minimize delay the packet must go through anet with a low latency

NNTP

2 maximize throughput the packet must go over a netthat maximizes throughput

SNMP

4 maximize reliability the packet must be routedover the most reliable net

SMTP data, DNS zone transfer,

8 minimize cost the packet must be routedover the least expensive

route

Telnet, FTP control, SMTPcommands, DNS UDP

15 maximize security the packet must be takenover the most secure net


161/467

IP ( + )

16 IP

65 535

IP, ICMP, IGMP 16

,


162/467

IP

( 0)

IP, ICMP, IGMP 17

TTL ( )


163/467

,

1

, TTL = 0

TTL = 0,

IP, ICMP, IGMP 18


164/467

,

( NAT

)

IP, ICMP, IGMP 19


165/467

()

( 4)

n (16)

IP, ICMP, IGMP 20

Sender T Receiver-T


166/467

()

:

( 5)

0,

0,

IP, ICMP, IGMP 21

-


167/467

IP, ICMP, IGMP 22

n bits

n bits

all 0s

n bits

n bits

n bits

n bits

Sender

Section 1

Complement

PacketSum

Section 2

Checksum

Section k

If the result is 0, preserve

the packet otherwisethrow it away

Checksum

Checksum

n bits

n bits

n bits

n bits

n bits

n bits

Receiver

Section 1

Complement

Sum

Section 2

Checksum

Section k

Result

-


168/467

IP : 01 00 F2 03 F4 F5 F6 F7 00 00 (00 00 e

).

16-

0100 F203 F4F5 F6F7

IP, ICMP, IGMP 23

0000 0001 0000 0000


169/467

0000 0001 0000 0000

1111 0010 0000 00111111 0100 1111 0101

+ 1111 0110 1111 0111

1101 1110 1110 1111

+ 101101 1110 1111 00011-

0010 0001 0000 1110

:

01 00 F2 03 F4 F5 F6 F7 21 0

IP, ICMP, IGMP 24


170/467

IP, ICMP, IGMP 26


171/467

MTU (Maximum Transmission

Unit)

(IP)

( ),

IP, ICMP, IGMP 27

MTU (aximum Transmission Unit)


172/467

IP, ICMP, IGMP 28

Topology MTU (in bytes)

Hyper-channel 65 535

16 MB/s Token Ring 17 914

802.4 Token Bus 8166

4 MB/s Token Ring 4464

FDDI 4352

DIX Ethernet 1500

Point to Point Protocol (PPP) 1500

802.3 Ethernet 1492

Serial Line IP (SLIP) 1006

X.25 and ISDN 576

ARCnet 508

-


173/467

IP, ICMP, IGMP 29

4KB Datagram for 192.168.20.60

Happy192.168.10.10

Sneezy192.168.10.40

Queen192.168.10.3192.168.20.3

6 packets for 192.168.20.60

6

4 2

1

5 3

-


174/467

IP, ICMP, IGMP 30

Sneezy192.168.10.10

modem

modem

modem

modem

Datagram for 192.168.30.10

192.168.10.3192.168.100.1

192.168.30.1

172.16.110.1

192.168.100.100172.16.100.1

192.168.110.100

172.16.100.2

Carriernetwork


175/467

IP, ICMP, IGMP 31

+

U

U,


176/467

(16 )

(13 )

()

IP

IP, ICMP, IGMP 32

(3 )


177/467

IP, ICMP, IGMP 33

.

.

.

Flag number Bit value Interpretation

1 0 always set to zero, and preserved for futureuse

2 0 fragmentation allowed

1 no fragmentation

3 0 last fragment1 more fragments to come

?


178/467

IP, ICMP, IGMP 34

Inputan IP packetDetermine the size of the datagramIf (size >MTU) then

If (do not fragment =1)

Discard the datagram

Send ICMP message

Go backElse

Calculate the max size

Fragment the datagram

Add header to each datagram

Send the datagram

Go back

ElseSend the datagram

End


179/467

IP, ICMP, IGMP 35

.

Input-datagram from processing

If (offset = 0 and LF=0) then

Put the datagram into a queue

Go backSearch through the reassembly table

If (failure) then create a new entry

Insert the fragment into the LL

If (all fragments in) then

Reassemble

Push the datagram to transport

Go backElse

If (time-out expired) then discard everything and send ICMP message

Go back

/


180/467

IP, ICMP, IGMP 36

IP HEADER Original datagram data area

IP Hdr Data IP Hdr Data IP Hdr Data 3

-


181/467

IP, ICMP, IGMP 37

TCP 4444 ( TCP ). Rainy MTU= 1492 bytes TCP . TCP IP 20 .

Sunny Network B MTU = 508bytes. Network C MTU = 572 bytes.

Cloudy Sunny.

.


182/467

IP, ICMP, IGMP 38

Network A

Network B

Network C

The size of the segmentdelivered to IP from TCP is4444 bytes

MTU = 508

Cloudy Sunny

MTU = 1492

MTU = 572Rainy

4444 bytes20 bytes


183/467

IP, ICMP, IGMP 39

header

header

header

header

header

data

data

data

data

data

First fragment

Second fragment

Third fragment

Last fragment

20 bytes 1472 bytes

1472 bytes

20 bytes

20 bytes

20 bytes

1472 bytes

28 bytes

1492 bytes

Rainy

IP ( + 20 IP )


184/467

IP, ICMP, IGMP 40

fragment fragmentID

reservedflag

mayfragment

morefragments

fragmentoffset

packetlength

1 321 0 0 0 0 4464

fragment fragmentID

reservedflag

mayfragment

morefragments

fragmentoffset

packetlength

1 321 0 0 1 0 1492

2 321 0 0 1 184 1492

3 321 0 0 1 368 1492

4 321 0 0 0 552 48

IP

IP ( + 20 IP )

Network B


185/467

IP, ICMP, IGMP 41

fragment fragmentID

reservedflag

mayfragment

morefragments

fragmentoffset

packetlength

1 321 0 0 1 0 508

2 321 0 0 1 61 508

3 321 0 0 1 122 508

4 321 0 0 1 183 28

fragment fragmentID

reservedflag

mayfragment

morefragments

fragmentoffset

packetlength

1 321 0 0 1 184 508

2 321 0 0 1 245 508

3 321 0 0 1 306 508

4 321 0 0 1 367 28

Network C


186/467

IP, ICMP, IGMP 42

fragment fragmentID

reservedflag

mayfragment

morefragments

fragmentoffset

packetlength

1 321 0 0 0 552 48

fragment fragmentID

reservedflag

mayfragment

morefragments

fragmentoffset

packetlength

1 321 0 0 1 368 572

2 321 0 0 1 437 572

3 321 0 0 1 506 388

Transport Transport

IP


187/467

IP, ICMP, IGMP 43

Header-addition

Forwarding

Reassembly

FragmentationProcessing module

DLLDLL

MTU table

Reassemblytable

Forwardingtable

Data and DA

IP

IP IP NH

IP

Data

IP NH

IP

IP


188/467

ICMP

(Internet Control Message Protocol)

IP, ICMP, IGMP 44

ICMP?


189/467

IP best effort

:

ICMP

IP, ICMP, IGMP 45

ICMP


190/467

IP

TTL 0

ICMP

IP, ICMP, IGMP 46

ICMP -


191/467

,

ICMP IP

( )

IP, ICMP, IGMP 47

ICMP


192/467

ICMP

Destination unreachable

Time Exceeded

Source Quench

Ping

Ridirect Traceroute

IP, ICMP, IGMP 48

Type Name Type Name


193/467

IP, ICMP, IGMP 49

Type Name

---- -------------------------0 Echo Reply

1 Unassigned

2 Unassigned

3 Destination Unreachable

4 Source Quench

5 Redirect

6 Alternate Host Address

7 Unassigned

8 Echo

9 Router Advertisement

10 Router Solicitation

Type Name

---- -------------------11 Time Exceeded

12 Parameter Problem

13 Timestamp

14 Timestamp Reply

15 Information Request

16 Information Reply

Destination unreachable


194/467

ICMP

ICMP

IP, ICMP, IGMP 50

-


195/467

IP, ICMP, IGMP 51

Happy192.168.10.10

Doc192.168.10.60

Queen192.168.10.3192.168.20.3

Error:network unreachable

Packet for 192.168.30.10

-


196/467

IP, ICMP, IGMP 52

Happy192.168.10.10

Packet for UDP port 69

Doc192.168.10.60

Error: Port unreachable2

1


197/467

IP, ICMP, IGMP 53

192.168.30.20

192.168.10.10

192.168.10.3

192.168.30.3

16 KB packet for 192.168.10.10

Do not fragment

1.5KB MTU

Error: fragmentation required

1

2

Source Quench


198/467

( )

IP, ICMP, IGMP 54

Redirect -


199/467

IP, ICMP, IGMP 55

R1 redirect

192.16.1.1

10.1.1.1

R2

Redirect


200/467

IP, ICMP, IGMP 56

192.168.10.10

192.168.30.10

192.168.30.1

192.168.10.1

Doc

1 192.168.20.60

King

192.168.20.3

192.168.10.3

Queen

Happy

Packet for 192.168.30.10

2

3

3


201/467

IP, ICMP, IGMP 57

IP L

L=0, ICMP Time exceeded

TTL

IP Parameter problem


202/467

IP, ICMP, IGMP 58

IP

, IP

IP Parameter problem

Time stamp and Time stamp reply


203/467

IP, ICMP, IGMP 59

ICMP Echo Request and Echo Reply


204/467

IP, ICMP, IGMP 60

Ping

ICMP Echo

Traceroute

ICMP Echo 1 TTL.

TTL=1, TTL=2

. Time exceeds

Echo request, Echo reply


205/467

IP, ICMP, IGMP 61

Happy192.168.10.10

Echo request

Duck192.168.10.40

Echo reply2

1

Query messages

Echo request cho reply


206/467

IP, ICMP, IGMP 62

192.168.30.10

192.168.10.10

Doc

1

2 fragments containing Echo reply

192.168.30.3

192.168.10.3

Queen

Happy

2KB Echo request for 192.168.20.10

4

3

2

Solicitation advertisement


207/467

IP, ICMP, IGMP 63

defaultgateway, (route discovery) ICMP router solicitation

(224.0.0.2 )

advertisement ICMP

Advertisement

Router discovery -

KingHappyadvertisement preference 102


208/467

IP, ICMP, IGMP 64

192.168.30.10

192.168.30.10

192.168.20.60

192.168.30.1

192.168.10.1

192.168.10.1

192.168.10.1Queen

Sleepy

2

1router solicitation

advertisement preference

advertisement preference 10

Router discovery -


209/467

IP, ICMP, IGMP 65

192.168.30.10

192.168.30.10

192.168.20.60

192.168.30.1192.168.10.1

192.168.10.1192.168.10.1

Queen

King

Sleepy

Happy

4

32

packet for 192.168.30.101

ICMP


210/467

ICMP IP

,

IP, ICMP, IGMP 66

ICMP


211/467

IP, ICMP, IGMP 67

ICMP

ype

Code

Checksum

?

ICMP ?


212/467

IP, ICMP, IGMP 69

?

?

ICMP

ICMP


213/467

IP, ICMP, IGMP 70

ICMP

MTU ICMP


214/467

.

MTU ,

ICMP

ICMP

MTU.

MTU.

,

MTU.

IP, ICMP, IGMP 71

MTU -

192.168.100.100172 16 100 1

1500 byte


215/467

IP, ICMP, IGMP 72

192.168.10.10

192.168.100.10

modem modem

172.16.100.1

Carriernetwork

192.168.100.70

172.16.60.70

1500 byteMTU

1500 byteMTU

512 byte

MTU

MTU

1500 bytes packetfor 192.168.100.10

1

2

ICMP

(firewalls)


216/467

IP, ICMP, IGMP 73

ICMP

MTU

ICMP

Echo


217/467

IGMP

(Internet Group Management Protocol)

IP, ICMP, IGMP 74


218/467

,

IP, ICMP, IGMP 75

Destination


219/467

IP, ICMP, IGMP 76PIO TCP/IP Networking 76

Unicast

Source

Router

Router

Source

Multicast

Destination

Destination

Destination

Destination

Destination


220/467

D (224.0.0.0239.255.255.255

224.0.0.0 224.0.0.25

224.0.0.1

IP, ICMP, IGMP 77


221/467

IP, ICMP, IGMP 78

IGMP e

.

Sleepy


222/467

IP, ICMP, IGMP 79

Happy192.168.10.10

py

192.168.20.60

Queen192.168.10.3192.168.20.3

224.1.2.3

Sneezy192.168.10.40

224.1.2.3

?


223/467

IP, ICMP, IGMP 80

R IGMP Membership-Report


224/467

224.2.0.1

DR za

pripadnost na grupata

DR

DR

IP, ICMP, IGMP 81

R

R: ReceiverDR: Designated Router

Network A

DR


225/467

R e

,

DR

IP, ICMP, IGMP 82

Data to 224.2.0.1

R

R

R: Receiver

DR: Designated Router

IGMP Leave-Group

Network A

IGMP

8 bytes20 bytes14 bytes


226/467

IP, ICMP, IGMP 83

Ethernet Header IP header IGMP

Message

Version

(= 0)

Type

(=1-2)(unused)

32-bit Class D address

Checksum

IGMP 8 (query report)

IGMP


227/467

IP, ICMP, IGMP 84

Queen192.168.10.3192.168.20.3

joining 224.0.1.1 sent to 224.0.1.1

Sneezy192.168.10.40

Doc192.168.10.30

Merlin192.168.10.5

Happy192.168.10.10


228/467

NAT, DHCP, ARP 1

5

NAT, DHCP, ARP


229/467

IPv4

(NAT)

(DHCP)

() IP

RP (Address Resolution

Protocol)

NAT, DHCP, ARP 2


230/467

IPv4

NAT, DHCP, ARP 3


231/467

NAT (Network

Address Translation)

DHCP (Dynamic Host Configuration Protocol)

NAT, DHCP, ARP 4


232/467

NAT, DHCP, ARP 5

IP

NAT (Network Address Translation)

?


233/467

NAT, DHCP, ARP 6

,

,

NAT

Src. Add. Dest. Add. Src. Add. Dest. Add.


234/467

NAT, DHCP, ARP 7

Localhost

Remotehost

NAT10.1.1.1 193.1.1.1.

10.1.1.1 193.1.1.1Before NAT

Outbound packet

14.38.1.1 193.1.1.1After NAT

Outbound packet

Dest. Add.14.38.1.1

Src. Add.193.1.1.1

Before NAT

Return packet

Dest. Add.10.1.1.1

Src. Add.193.1.1.1

After NAT

Return packet

NAT IP

Internet

NAT -

(Inside local address)

Internal IP header


235/467

NAT, DHCP, ARP 8

(Inside globaladdress)

(Outside localaddress)

(Outside globaladdress)

Source Address

10. 1. 1. 1

DestinationAddress

193. 1. 1. 1

Source Address

14. 38. 1. 1

DestinationAddress

193. 1. 1. 1

Inside local address Outside local address

NAT

Inside global address Outside global address

External IP header

NAT


236/467

NAT, DHCP, ARP 9

(

)

NAT

, .

PAT (Port Address Translation) Dynamic

NAT with overload Masquerading

NAT

Inside local

Address

Inside global

Address


237/467

NAT, DHCP, ARP 10

NAT

PAT

Inside local

address

Inside local

Port

Inside global

address

Outside

Port

Transport

Protocol

172.18.3.1 1400 25.8.3.2 80 TCP

172.18.3.2 1401 25.8.3.2 80 TCP

... ... ... ... ...

172.18.3.1 25.8.3.2

172.18.3.2 25.8.3.2

... ...

NAT -


238/467

NAT, DHCP, ARP 11

ISP

, NAT

NAT round-robin

NAT


239/467

NAT, DHCP, ARP 12

NAT -


240/467

NAT, DHCP, ARP 13

checksum IP

checksum

,

nd-to-end


241/467

NAT, DHCP, ARP 14

,

IP


242/467

IP

(subnet mask) (default

gateway)

(DNS

)

NAT, DHCP, ARP 15


243/467

, ,

NAT, DHCP, ARP 16

Dynamic Host Configuration

Protocol (DHCP)


244/467

NAT, DHCP, ARP 17

DHCP

RARP RP BOOTP

DHCP BOOTP

UDP

RARP (Reverse ARP)

RARP ARP


245/467

NAT, DHCP, ARP 18

IP RARPrequest

IP 0.0.0.0 255.255.255.255. MAC

,

RARP IP IP

.default gateway DNS

1985 .

BOOTP (BOOTstrap Protocol)

IP

( 199 )


246/467

NAT, DHCP, ARP 19

( 1995.)

IP , , IP default

gateway, IP DNS

BOOTP DHCP

IP

DHCP

(


247/467

( )

(

)

BOOTP

DHCP ,

DHCP

NAT, DHCP, ARP 20

DHCP?

DHCP


248/467

NAT, DHCP, ARP 21

DHCP

,

.

DHCP ,

IP

DHCP

DHCP DHCP

DHCP


249/467

NAT, DHCP, ARP 22

IP Lease Selection

IP Lease Request

IP Lease Offer

IP Lease

Acknowledgment

DHCP

1 DHCPDISCOVER DHCP


250/467

NAT, DHCP, ARP 23

1 DHCPDISCOVER DHCP

2 DHCPOFFER

3 DHCPREQUEST

4 DHCPDECLINE

5 DHCPACK

6 DHCPNAK

7 DHCPRELEASE

8 DHCPINFORM

DHCP 1

DHCP Client00:a0:24:71:e4:44 DHCP Server

DHCPDISCOVERS t t 255 255 255 255


251/467

NAT, DHCP, ARP 24

DHCP Discover

DHCP Offer

Sent to 255.255.255.255

DHCP Server


DHCP Server

DHCPOFFER

DHCPOFFER

DHCPDISCOVER

Source IP Address = 0.0.0.0

Dest IP Address = 255 255 255 255

DHCP 1 (.)

DHCP


252/467

NAT, DHCP, ARP 25

DHCP ServerDHCP Client

Dest. IP Address = 255.255.255.255Hardware Address = 08004....

IP Router

DHCPOFFER


Dest. IP Address = 255.255.255.255

Offered IP Address = 131.107.8.13

Client Hardware Address = 08004...Subnet Mask = 255.255.255.0

Length of Lease = 72 hours

Server Identifier = 131.107.3.24

DHCP

DHCP 2

DHCP Request with ACK


253/467

NAT, DHCP, ARP 26

.


DHCP Server

DHCPREQUEST

DHCPACK

DHCPREQUEST


Dest. IP Address = 255.255.255.255

Hardware Address = 08004....

Requested IP Address = 131 107 8 13

DHCP 2 (.)


254/467

NAT, DHCP, ARP 27

DHCP ServerDHCP Client

Requested IP Address = 131.107.8.13Server Identifier = 131.107.3.24

IP Router

DHCPACK


Dest. IP Address = 255.255.255.255

Offered IP Address = 131.107.8.13

Client Hardware Address = 08004...

Subnet Mask = 255.255.255.0Length of Lease = 72 hours

Server Identifier = 131.107.3.24

DHCP Option: Router = 131.107.8.1

DHCP

DHCP Request with ACK

DHCP Client

00:a0:24:71:e4:44 DHCP Server


255/467

NAT, DHCP, ARP 28

( 50% )(ipconfig/renew)

DHCP DHCPNACK, .

00:a0:24:71:e4:44 DHCP Server

DHCP Server

DHCPREQUEST

DHCPACK

DHCP IP

(ipconfig/release)


DHCP Server

DHCPRELEASE

DCHP Release


256/467

ARP (Address Resolution Protocol)

NAT, DHCP, ARP 29

MAC


257/467

NAT, DHCP, ARP 30

( ) MAC

48


258/467

NAT, DHCP, ARP 31

48

( )

3 (IEEE).

3 .

Vendor code or OUI(Organizationaly UniqueIdentifier), assigned by IEEE

Vendors assigned. Vendorsare responsible for theuniquenss

01 12 23 34 a3 b4

()


259/467

NAT, DHCP, ARP 32

, ()

,

,

IP MAC

IP


260/467

NAT, DHCP, ARP 33

IP .

MAC

IP

The Address Resolution Protocol (ARP)

ARP


261/467

NAT, DHCP, ARP 34

ARP

ARP

,

ARP

IP

ARP RARP

ARP RARP (Reverse ARP)


262/467

NAT, DHCP, ARP 35

RARPEthernet MAC

address(48 bit)

ARPIP address(32 bit)

ARP RARP (Reverse ARP) IP MAC

ARP?

IP


263/467

NAT, DHCP, ARP 36

IP IP (ARP request).

IP

ARP

IP ARP


264/467

NAT, DHCP, ARP 37

IP ARP

ARP

ARP


265/467

NAT, DHCP, ARP 38

ARP

IP ( )


266/467

NAT, DHCP, ARP 39

IP ( ) ARP 9

Hardware type

Protocol type

Hardware address length Protocol address length

Message type

Source hardware address

Source IP address

Destination hardware address Destination IP address

ARP

Destination

address

6

ARP Request or ARP Reply

28

Source

address

6 2

CRC

4

Type

0x8060Padding

10

Ethernet II header


267/467

NAT, DHCP, ARP 40

Hardware type (2 bytes)

Hardware address

length (1 byte)

Protocol address

length (1 byte)Operation code (2 bytes)

Target hardware address*

Protocol type (2 bytes)

Source hardware address*

Source protocol address*

Target protocol address*

* Note: The length of the address fields is determined by the corresponding address length fields

RP TCP/IP

SMTP FTP

TELNET DNS

HTTP Application

Presentation


268/467

NAT, DHCP, ARP 41

Transport

Network

Application

Physical

TELNET DNS PresentationSession

TransportTCP UDP

NetworkIGMPICMP

IP

DHCPARP

Data Link

Physical

Protocols defined by the

underlying networks

Domain

Happy

Sneezy

DNS serverfor itm.se

Sl


269/467

NAT, DHCP, ARP 42

Happy (ARP ),

sleepy (ping sleepy).

IP IP

sneezy DNS IP R

172.16.5.3172.16.5.2172.16.5.1

Domainitm.se

SneezySleepy

R

172.16.5.4

1. Happy ARP request Sneezy

2. Sneezy ARP response

3 Happy DNS neezy


270/467

NAT, DHCP, ARP 43

3. Happy DNS neezy IP Sleepy

4. Sneezy IP Sleepy

5. IP Sleepy, Happy

Sleepy

6. HappyARP request Sleepy

7. Sleepy ARP response

8. Happy leepy


271/467

NAT, DHCP, ARP 44

E7E6

H0 H1 H4 H5 H8 H9

E1I1I0 E0 E4I4 E5I5 E8I8 E9I9

I7I6E3

I11

E2

I10 LAN 2 LAN 3LAN 1R1 R2

IP ? 4 : ping H9.

?

ARP


272/467

NAT, DHCP, ARP 45

? ARP

. . ARP

IP ?

ARP (request)

Proxy ARP

( )

access router


273/467

NAT, DHCP, ARP 46

access router

H0 H1 H4 H5

E1I1I0 E0 E4I4 E5I5

E3

I11

E2

I10 LAN 2LAN 1R1

H0 asks R1 forMAC address

of H4R1 can provide an answer since ithas this MAC address in its cache

Gratuitous ARP

ARP


274/467

NAT, DHCP, ARP 47

ARP IP

IP

Gratuitous ARP

DHCP


275/467

6

IPv6,

IPv6


276/467

IPv4

IPv6, 2


277/467

IP 6

IPv4

(CIDR, NAT, DHCP

, )


278/467

, )

( Best effort )

IPv6, 4

IPv6

128-


279/467

40

IPSec

IPv6, 5

6


280/467

6

(40 )

IPv6, 6

0 311612 244


281/467

IPv6, 7

0 3116

flow labelversion traffic class

next headerpayload length hop limit

destination address

source address

12 244

(4 )

(8 )


282/467

(8 )

(20 )

(16 )

(8 )

(8 )

(128 )

(128 )

IPv6, 8

6 IPv6


283/467

6 IPv6

IPv6, 9


284/467

(

)

IPv6, 10


285/467

65535 (16) 64

. 0

IPv6, 11


286/467

()

IP e (TCP,

UDP)

( TTL IPv4)

IPv6, 12

()

6 ,


287/467

Hop by hop

Routing

Fragment

Authentication

Encrypted security Destination options

IPv6, 13

()


288/467

a

IPv6, 14

s d


289/467

IPv6, 15

g

gs

g

Anycast

a

as

a

Link local


290/467

Site local

IPv6, 16

Global Link localSite local

0 6432 96

TLA NLA Interface identifierSLA


291/467

TLATop Level Aggregator assigned for 8Kmajor providers(13+3bits)

NLANext Level Aggregator assigned for smaller providers

SLASite Level Aggregator subnetnumbers within organizations (16bits)

IPv6, 17

0 82 4 6 10 12 14

NLA1 NLA2 NLA3

*

()


292/467

( ) IPv4,

( IPv4)

IGMP IPv6

ICMP (

IGMP IPv4)

IPv6, 18

IPv6

( IPv4-

) :


293/467

)

:

IPv6, 19

IPv6

3ffe:0501:0008:0000:0260:97ff:fe40:efab


294/467

3ffe:501:8:0:260:97ff:fe40:efab

3ffe:501:8::260:97ff:fe40:efab

ff02:0000:0000:0000:0000:0000:0000:0001

ff02:0:0:0:0:0:0:1

ff02::1

IPv6, 20

::


295/467

::1

loopback ( 127.0.0.1 IPv4) ping ::1

IP

IPv6, 21


296/467

Stateless

( 3

) Local Link (

)

Stateful

DHCP kaj IPv4

IPv6, 22

IPv4 IPv6

IPv6


297/467

6

4

4

IPv6, 23


298/467

6

(dual

stack)

4

IPv6, 24

dual stack

6


299/467

4

IPv6, 25

TCP

IPv4 IPv6

TCP

IPv6

TCP

IPv4

IPv4-onlyIPv6-only

6


300/467

IPv4,

IPv6 IPv4

IPv4 IPv6

IPv6, 26

IPv6

IPv6


301/467

IPv4

IPv6, 27

IPv6 packet

IPv4 header IPv6 packet

IPv6 only IPv6 only HappyFunny

destinationsource

IPv4


302/467

IPv6, 28

IPv6

Data

IPv6

DataIPv6 /IPv4 IPv4/IPv6

Queenrouter King-router

IPv4 King

IPv6 Happy

Data

IPv4Network


303/467


304/467

IPv6, 30

(Classless inter-domain routingCIDR)

IP


305/467

IPv6, 31

IP IP

IP


306/467

IPv6, 32

(forwarding)


307/467

(forwarding)

(routing)

TTL

ICMP ....

IPv6, 33

Switching fabric

Output PortsForwarding

Table

ForwardingD i i

Input Ports + Processing


308/467

IPv6, 34

Decision

ForwardingTable

ForwardingDecision

ForwardingTable

ForwardingDecision

IP


309/467

(

) Next hop

() ( ). IP

,

IPv6, 35

,


310/467

()

.

IPv6, 36

direct/(conn )

Destination Next Hop Interface

R1


311/467

direct/(conn.) R1 IP,

IP ,

.

IPv6, 37

10.1.0.0/24

10.1.2.0/24

10.2.1.0/24

10.3.0.0/1620.1.0.0/16

20.2.1.0/28

R3

direct /(conn.)

direct /(conn.)

R3R2

R2

Eth0/0

Eth0/2

Eth0/0

Eth0/0serial0

serial0

Destination Next Hop

10.1.0.0/2410.1.2.0/2410.2.1.0/2410.3.1.0/24

20.2.0.0/1630.1.1.0/28

R3directdirectR3

R2R2


10.1.0.0/2410.1.2.0/2410.2.1.0/2410.3.1.0/24

20.1.0.0/1620.2.1.0/28

R1R1directR4

directdirect


10.1.0.0/2410.1.2.0/2410.2.1.0/2410.3.1.0/24

20.1.0.0/1620.2.1.0/28

R2R2R2R2

R2direct


312/467

IPv6, 38

to:

20.2.1.2


10.1.0.0/2410.1.2.0/24

10.2.1.0/2410.3.1.0/2420.1.0.0/1620.2.1.0/28

directR3

R3R3R3R3

H1

R1 R2

R3 R4

H2

10.2.1.0/24

20.1.0.0/1610.1.2.0/24

10.1.0.0/24 10.3.0.0/16

20.2.1.0/28

20.2.1.2/28


10.1.0.0/2410.1.2.0/24

10.2.1.0/2410.3.1.0/2420.1.0.0/1620.2.1.0/28

directdirect

R4directR4R4


10.1.0.0/2410.1.2.0/24

10.2.1.0/2410.3.1.0/2420.1.0.0/1620.2.1.0/28

R3R3

R2directdirectR2


10.1.0.0/2410.1.2.0/2410.2.1.0/2410.3.1.0/2420.2.0.0/1630.1.1.0/28

R3directdirectR3R2R2


10.1.0.0/2410.1.2.0/2410.2.1.0/24

10.3.1.0/2420.1.0.0/1620.2.1.0/28

R1R1direct

R4directdirect


10.1.0.0/2410.1.2.0/2410.2.1.0/24

10.3.1.0/2420.1.0.0/1620.2.1.0/28

R2R2R2

R2R2direct


313/467

IPv6, 39

to:

20.2.1.2


10.1.0.0/2410.1.2.0/24

10.2.1.0/2410.3.1.0/2420.1.0.0/1620.2.1.0/28

directR3

R3R3R3R3

H1

R1 R2

R3 R4

H2

10.2.1.0/24

20.1.0.0/1610.1.2.0/24

10.1.0.0/24 10.3.0.0/16

20.2.1.0/28

20.2.1.2/28


10.1.0.0/2410.1.2.0/24

10.2.1.0/2410.3.1.0/2420.1.0.0/1620.2.1.0/28

directdirect

R4directR4R4


10.1.0.0/2410.1.2.0/24

10.2.1.0/2410.3.1.0/2420.1.0.0/1620.2.1.0/28

R3R3

R2directdirectR3

R4 R3


314/467

Network route IP ( 10.0.2.0/24)

Host route IP ( 10.0.1.2/32) Default route

( default gateway gatewayof last resort)

Loopback address ( )

IPv6, 40

Default route?

(

)


315/467

)

IPv6, 41

?


316/467

,

IPv6, 42

ICMP


317/467

ICMP

IPv6, 43

(1) IP datagram

R1

(2) IP datagram

(3) ICMP redirect

DestinationNext Hop10.1.0.0/24

R2

DestinationNext Hop

10.1.0.0/24

R1

Ethernet

H1

R1 R2

ICMP

Windows


318/467

IPv6, 44

Cisco


319/467

IPv6, 45

(Forwarding) (Routing)

:


320/467

IPv6, 46

:

1. :

?

2. :

?

IP

(, ) IP


321/467

IPv6, 47

,

IP ,

,

IP

UDP TCPRouting

Protocol

Static

routing


322/467

IPv6, 48

Input

queue

Lookup next

hopDestination

address local?

Yes

Send

datagram

IP forwarding

enabled?

No

Discard

Yes No

Demultiplex

forwarding(routing)

table

IP module

Data Link Layer

IP

1. IP (

0)

2 IP

IP


323/467

IPv6, 49

2. IP

3. IP

4.

5. TTL

6. ( )

7.

8.

9. ICMP ( )

IP


324/467

IPv6, 50

IP


325/467

IPv6, 51

IP ( )

, , ,


326/467

IPv6, 52

Next hop( )

, default route

default route

default route No route to host ICMP

(CIDR)


327/467

IPv6, 54

(Longest prefix match)

Host route 32 Default router 0

32

ength

.

: ,

.


328/467

IPv6, 55

8

24

Prefixes

PrefixLe

128.9.0.0/16 142.12.0.0/1965.0.0.0/8

128.9.16.14

128.9.172.0/21

128.9.176.0/24

128.9.16.0/21

128.9.16.14 128.9.16.0/21 21 128.9.16.14 128.9.0.0/16 16

128.9.16/21

A

0 1

D

Root

Route Prefixes

A 0*


329/467

IPv6, 56

0

0

0

1

1

0

0 0

0 0

1

1

1 1

B

C E

F G H I

B 01000*

C 011*

D 1*

E 100*

F 1100*

G 1101*

H 1110*

I 1111*

CIDR ISP X 16 C 200.23.16.0 200.23.31.0 (200.23.16/20)

AdjacentISP ISP X

1 Destination Interface

200.23.16/21 21


330/467

IPv6, 57

200.23.16.0/24, 200.200.17.0/24

200.23.18.0/24, 200.200.19.0/24200.23.20.0/24, 200.200.21.0/24

200.23.22.0/24, 200.200.23.0/24

Largecompany

200.23.16.

0/21

Mediumcompany

200.23.24.0/

22

200.23.24.0/24

200.23.25.0/24200.23.26.0/24

200.23.27.0/24

Smallcompany

200.23.28.

0/23

200.23.28.0/24

200.23.29.0/24

Tinycompany

200.23.30.

0/24

router

Destination Interface

200.23.16/20 1

200.23.24/22 3

200.23.28/23 4

200.23.30/24 5

0.0.0.0 1

23 4

5

()

.


331/467

IPv6, 58


10.1.0.0/2410.1.2.0/2410.2.1.0/24

10.3.1.0/2420.0.0.0/8

R3directdirect

R3R2


10.1.0.0/2410.1.2.0/2410.2.1.0/2410.3.1.0/24

20.2.0.0/1620.1.1.0/28

R3directdirect

R3

R2R2

?

/


332/467

IPv6, 59

?

?

?

? .


333/467

7,


334/467

Default route

A

, 2

,,

IP


335/467

IP ,

()

, 3

(

)


336/467

, 4

( )

,


337/467

()

,

,

, 5


338/467

, 6


339/467

(

)

, 7

- R1-R2,

AR2


340/467

, 88

B R2

C R3

B

C

R1

R2

R3 R4

R1s routing table

A

direct

(connected)

Next hopDestin

ation

?


341/467

stub network

, 9

Default Route

stub networks


342/467

default route

Default route

, 10

( )

,


343/467

, 11

Routing versus Routed Protocols

Routing protocols ( )


344/467

Routed protocols ( )

IP (kaj Internet), IPX (kaj Novell)

, 12

( )


345/467

, 13


346/467

,

, 14

Ka


347/467

( )

, 15

Ka (.)

/


348/467

/

, 16

Ka (.)


349/467

,

, 17

(flooding)


350/467

(flooding)

(random routing)

(hot-potato routing)

(Shortest path routing, Least cost routing)

, 18


351/467

A

B

C

D

E

FA

B

C

D

E

FA

B

C

D

E

F


352/467

,

, 20

A

B

C

D

E

F

A

B

C

D

E

F

A

B

C

D

E

F

B

C

D

E

F

B

C

D

E

FA

() ()


353/467

()

( -)

()

, 21

D

5

2

3

3

5C

A

B

12 Destin Next Distn


354/467

, 22

E F

11

2

C

A

B

D

2

11

21

ation hop ce

B B 2

C E 3

D E 4

E E 1

F E 2E F


355/467

(,

)

, 23

()


356/467

, 24

6

5

2

3

3

53

1

4 5

2

1

1

2

1


357/467

( backup)

, 25


358/467

, 26

(distance vector

protocols)


359/467

p )

(

)

-

, 29

140

140

:

, .

, ,

.


360/467

, 30

minimum (185 175, 210) = 175

Destination Next hop Distance 175

140km away

180km

140km 140+45=185

140+35=175

180+30=210

Routing Information Protocol (RIP)

koj e GGP


361/467

, 31


362/467

()

, 33

OSPF (Open Shortest Path First)

RIP


363/467

OSPF IPv6

, 34


364/467

, 36

IP ( )

(AutonomousSystems, AS)

A ()

( )


365/467

, 37

)

16

(Exterior gateways)

,

(Three Autonomous

Systems)

EGP IGP

AutonomousSystem 1


366/467

, 38

IGP AutonomousSystem 2

IGPAutonomous

System 3

EGP- Exterior Gateway ProtocolsIGP Interior Gateway Protocols

Intra-AS and Inter-AS Routing

Hosth2

A.a

C.b

B.a

Inter-AS routingbetween A and B


367/467

, 39

h2

a

b

b

a

aC

A

B

dc

A.c c

b

Hosth1

Intra-AS routingwithin AS A

Intra-AS routingwithin AS B

IGP versus EGP

Interior Gateway Protocols (IGP) Intra-domainProtocols (

) .

() .


368/467

, 40

Exterior Gateway Protocols (EGP) Inter-domainprotocols ( )

( )


369/467

, 41

(.)


370/467

, 42

( )

()

(.)


371/467

, 43

,

(AS).


372/467

, 44

(.)

TCP


373/467

, 45


374/467

8

RIP, OSPF

RIP


375/467

OSPF

RIP, OSPF 2

( )


376/467

( ) ( )

, .

a () .

RIP, OSPF 3


377/467

RIP, OSPF 4

R3 R4

R1 R2

0

0

1

1

22

5

5

33

0

0R3 R4

R1 R2

1

32

5

RIP (Routing Information Protocol)

/


378/467

/

( )

RIP, OSPF 5

?

()


379/467

0

a ()

RIP, OSPF 6

RIP


380/467

1( )

( )

RIP, OSPF 7

-


381/467

0

RIP, OSPF 8


382/467

( )

,

RIP, OSPF 99


383/467

RIP, OSPF 10

,

Dest. NH Cost

A loc. 0

A

Dest. NH Cost

B loc. 0

BA = 0

Dest.=destinationNH = Next Hop

1


384/467

RIP, OSPF 11

Dest. NH Cost

C loc. 0CDest. NH Cost

D loc. 0D

Dest. NH Cost

E loc. 0

E

Loc.= Cost =

Dest. NH Cost

A loc. 0

B B 1

D D 1

Dest. NH Cost

B loc. 0

A A 1

C C 1

E E 1


385/467

RIP, OSPF 12

D

A = 0, B=1, D=1

E

Dest. NH Cost

D loc. 0

A A 1

E E 1

C

A B

- Dest. NH Cost

A loc. 0

B B 1

D D 1

C B 2

E B 2

Dest. NH Cost

B loc. 0

A A 1

D D 2

C C 1

E E 1

Dest. NH Cost

C loc. 0

B B 1

A B 2

E E 1

D E 2


386/467

RIP, OSPF 13

A BDest. NH Cost

D loc. 0

A A 1

B A 2

E E 1

C E 2

D

C

D E 2

Dest. NH Cost

E loc. 0

B B 1

A B 2

D D 1

C C 1

E

a

a

Dest. NH Cost

A loc. 0

B B inf.

D D 1

C B i f

Dest. NH Cost

B loc. 0

A A inf

D A inf


387/467

RIP, OSPF 14

A

C B inf.

E B inf.C C 1

E E 1

B

D

B = 0, A = inf., D = inf. , C = 1, E = 1A = 0, B = inf., D = 1 , C = inf., E = inf.

inf. =

- a Dest. NH Cost

A loc. 0

B B inf.D D 1

C B inf.

E B inf.

Dest. NH Cost

B loc. 0

A A inf

D A inf

C C 1

E A 1

Dest. NH Cost

C loc. 0

B B 1A B inf

E E 1

D E 2


388/467

RIP, OSPF 15

A

E A 1

B C

Dest. NH Cost

D loc. 0

A A 1

B A inf.

E E 1

C E 2

D

Dest. NH Cost

E loc. 0

B B 1

A B inf

D E 1

C C 1

E

D=0, A=1, B=inf., E=1, C=2

E=0, B=1, A=inf., D=1, C=1

C=0, B=1, A=inf. , E=1, D=2

Dest. NH Cost

A loc. 0

B B inf.

D D 1

C D 3

E D 2

Dest. NH Cost

B loc. 0

A A inf

D E 2

C C 1

E E 1

Dest. NH Cost

C loc. 0

B B 1

A B inf

E E 1

- a


389/467

RIP, OSPF 16

A

E D 2 E E 1

B

E E 1

D E 2

C

Dest. NH Cost

D loc. 0

A A 1

B E 2

E E 1

C E 2

D

Dest. NH Cost

E loc. 0

B B 1

A D 2

D D 1

C C 1

E

D=0, A=1, B=2., E=1, C=2

E=0, B=1, A=2., D=1, C=1

Dest. NH Cost

A loc. 0

B D 3

D D 1

C D 3

E D 2

Dest. NH Cost

B loc. 0

A E 3

D E 2

C C 1

Dest. NH Cost

C loc. 0

B B 1

A E 3

E E 1

- a


390/467

RIP, OSPF 17

E D 2E E 1 D E 2

Dest. NH Cost

D loc. 0

A A 1

B E 2

E E 1

C E 2

Dest. NH Cost

E loc. 0

B B 1

A D 2D D 1

C C 1


391/467

RIP, OSPF 18

(). Counting-to-infinity problem (

)

Bouncing effect ( )

Counting to Infinity

f

: D

E

A B

C

D

Dest. NH Cost

A loc. 0

B D 3

D D 1


392/467

RIP, OSPF 19

D A

A Do.

A o D -

counting to infinity.

Dest. NH Cost

D loc. 0

A A 1

B E inf.

E E inf.

C E inf.

D

C D 3

E D 2

A

Counting to Infinity (.)

Dest. NH Cost

A loc. 0

B D 3

D D 1

C D 3

() B,

CE A, D


393/467

RIP, OSPF 20

Dest. NH Cost

D loc. 0

A A 1

B A 4

E A 3

C A 4 D

C D 3

E D 2

A

DA TTL=0.

c AD.

Counting to Infinity (.)Dest. Link Cost

A loc. 0

B D 5

D D 1

C D 5

E

A D

.

1.


394/467

RIP, OSPF 21

Dest. Link Cost

D loc. 0

A A 1

B A 4

E A 3

C A 4

D

E D 4

A

.

.

Dest. Link Cost

A loc. 0B D Inf.

D D 1

C D Inf.

,

(


395/467

RIP, OSPF 22

Dest. Link Cost

D loc. 0

A A 1

B E Inf.

E E Inf.

C E Inf.

D

E D Inf.

A

D , . .

)

Bouncing Effect e 10 1.

b .Dest. NH Cost

A loc. 0

B B 1

D D 1

Dest. NH Cost

B loc. 0

A A 1

D A 2

C C 1

Dest. NH Cost

C loc. 0

B B 1

A B 2

B A

inf.

i f

inf

inf.


396/467

RIP, OSPF 23

A

C B 2

E B 2

C C 1

E E 1

B

Dest. NH Cost

D loc. 0

A A 1

B A 2

E E 1

C A 3

D

C

E B 2

D B 3

Dest. NH Cost

E loc. 0

B B 1

A B 2

D D 1

C B 2

E

, A

B.

inf.

inf.

f

B AE.

AE .

Dest. NH Cost

A loc. 0

B B 1

D D 1

C B 4

Dest. NH Cost

B loc. 0

A A 1

D A 2

Dest. NH Cost

C loc. 0

B B inf

A B inf

C AB

Bouncing Effect (.)


397/467

RIP, OSPF 24

a

cd

e (10)

f

A

C B 4

E B 2C A 3

E E 1

B

Dest. NH Cost

D loc. 0

A A 1

B A 2

E E 1

C A 3

D

E B inf

D B inf

Dest. NH Cost

E loc. 0

B B 1

A B 2

D D 1

C B 4

E

C 10 .

E 1 11 > 4( )


398/467

RIP, OSPF 25

AE

BD, C 5.

E C 11.

C e, .

?

Count to Infinity


399/467

RIP, OSPF 26

( )

ouncing effect

() 1

- Split Horizon

( )

:

.


400/467

RIP, OSPF 27

Split horizon

Split horizon

: , ( )

: , (split horizon with poison reverse)

Split Horizon -

Dest. NH Cost

B l 0

B

Dest. NH Cost

C loc 0

C

Dest. NH Cost

A loc. 0

A

A=0 C=0

B=0, C=1 B=0, A=1


401/467

RIP, OSPF 28

B loc. 0

A A 1

C C 1

C loc. 0

B B 1

A B 2

B B 1

C B 2

B-C ,

.

count-to-infinity.

Split Horizon

Split horizon


402/467

RIP, OSPF 29

3 .

C

BA

A l 0

A:B 2

B: B 1

C: loc. 0

D: D 1

A B 2


403/467

RIP, OSPF 30

D

A: loc. 0

B: B 1

C: B 2D: B 2

A: A 1

B: loc. 0

C: C 1

D: D 1

A: B 2

B: B 1

C: C 1D: loc. 0

(.)

C

BA

A l 0 A=2,C=0,B=

1

=2,D=0,B=1

A: B 2

B: B 1

C: loc. 0D: D 1


404/467

RIP, OSPF 31

D

A: loc. 0

A: A infB: loc. 0

C: C 1

D: D 1

A

A: C 3

B: B 1

C: C 1

D: loc. 0

A=

,

D. D ,

updates .

(.)

C

BA

A l 0 A=2,C=0,B=

1

=2,D=0,B=1

A: B 2

B: B 1

C: loc. 0D: D 1


405/467

RIP, OSPF 32

D

A: loc. 0

A: D 4B: loc. 0

C: C 1

D: D 1

A

A: C 3

B: B 1

C: C 1

D: loc. 0

A=

.

Hold-down Timers

, (holddown timer) .


406/467

RIP, OSPF 33

.

Triggered Updates


407/467

RIP, OSPF 34

( )

RIP

1960-:

ARPANET

1970-: XNS (Xerox Network System) RIP


408/467

RIP, OSPF 35

RIP

1982: routed BSD Unix ( RIP)

1988: RIPv1 (RFC 1058) -

1993: RIPv2 (RFC 1388)

1998: RIPv2 (RFC 2453)

RIP - (

1)

16 ( 15)

point-to-point broadcast

IP


409/467

RIP, OSPF 36

IP

30

Hold down timer e 180 sec.

UDP

Documents

Preda Vanja