01 Osi Model & Tcpip

June 23, 2018 | Author: Suraj Sikarwar | Category: Transmission Control Protocol, Internet Protocol Suite, Internet Protocols, Communications Protocols, Telecommunications

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Short Description

networking...

Description

Interconnecting Networks with TCP/IP ZTE University

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Objectives

•

Upon completion of this chapter you will be able to perform the following tasks: –

Identify the IP protocol stack, its protocol layer functions, and commonly used IP protocols

Identify IP address classes, IP addresses, IP subnet masks, IP network numbers, subnet numbers, and possible host numbers. numbers.

–

ZTE University

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Introduction to TCP/IP Host

Host

Internet TCP/IP

ZTE University

•

Early protocol suite

•

Universal

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TCP/IP Protocol Stack

7

Application

6

Presentation

5

Session

4

Transport

Transport

3

Network

Internet

2

Data Link

Data Link

5

Application 4 3 2 1

1

Physical

ZTE University

Physical

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Application Layer Overview

File Transfer - TFTP FTP * - FTP * - NFS E-Mail - SMTP Remote Login - Telne elnett * - rlogi login n* Network Management - SNMP * Name Management - DNS*

Application

Transport Internet Data Link

*Used by the router Physical

ZTE University

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Transport Layer Overview

Application Transport

Transmission Control Protocol (TCP)

ConnectionOriented

User Datagram Protocol (UDP)

Connectionless

Internet Data Link Physical

ZTE University

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TCP Segment Format Bit 0

Bit 15 Bi Bit 16

Bit 31 Destination port (16)

Source port (16)

Sequence number (32) Acknowledgement number (32) Header length (4)

Reserved (6) Code bits (6)

20 Bytes

Window (16)

Checksum (16)

Urgent (16)

Options (0 or 32 if any) Data (varies) ZTE University

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Port Numbers

Application Layer

Transport Layer ZTE University

F T P

T E L N E T

S M T P

D N S

T F T P

S N M P

R I P

21

23

25

53

69

16 1

520

Port Numbers

UDP

TCP

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TCP Port Numbers

Source Port

Dest. Port

…

Telnet Z

Host Z

Host A

ZTE University

SP

DP

1028

23

…

Dest. port = 23. Send packet to my Telnet application.

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TCP Three Way Handshake/Open Connection

Host A

1

Host B

Send SYN (seq=100 ctl=SYN)

ZTE University

SYN received

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TCP Three Way Handshake/Open Connection

Host A

1

Host B

Send SYN (seq=100 ctl=SYN)

SYN received Send SYN, ACK 2 (seq=300 ack=101 ctl=syn,ack)

SYN received

ZTE University

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TCP Three Way Handshake/Open Connection

Host A

1

Host B

Send SYN (seq=100 ctl=SYN)

SYN received Send SYN, ACK 2 (seq=300 ack=101 ctl=syn,ack)

SYN received

3

Established (seq=101 ack=301 ctl=ack)

ZTE University

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TCP Simple Acknowledgment Sender

ZTE University

Receiver

•

Window size = 1

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TCP Simple Acknowledgment Sender

Receiver

Send 1

ZTE University

Receive 1

•

Window size = 1

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TCP Simple Acknowledgment Sender

Receiver

Send 1

Receive 1 Send ACK 2

Receive ACK 2

ZTE University

•

Window size = 1

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TCP Simple Acknowledgment Sender

Receiver

Send 1

Receive 1 Send ACK 2

Receive ACK 2

Send 2

ZTE University

Receive 2

•

Window size = 1

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TCP Simple Acknowledgment Sender

Receiver

Send 1

Receive 1 Send ACK 2

Receive ACK 2

Send 2

Receive 2 Send ACK 3

Receive ACK 3

ZTE University

•

Window size = 1

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TCP Simple Acknowledgment Sender

Receiver

Send 1

Receive 1 Send ACK 2

Receive ACK 2

Send 2

Receive 2 Send ACK 3

Receive ACK 3 Send 3

ZTE University

Receive 3

•

Window size = 1

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TCP Simple Acknowledgment Sender

Receiver

Send 1

Receive 1 Send ACK 2

Receive ACK 2

Send 2

Receive 2 Send ACK 3

Receive ACK 3 Send 3

Receive 3 Send ACK 4

Receive ACK 4 ZTE University

Window size = 1

•

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TCP Sequence and Acknowledgment Acknowledgment Numbers

Source Port

Dest. Port

Sequence #

Acknowledgement #

…

I just sent #10.

Source Dest. Seq. Ack. 1028

23

ZTE University

10

1

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TCP Sequence and Acknowledgment Acknowledgment Numbers

Source Port

Dest. Port

Sequence #

Acknowledgement #

I just sent #10.

…

I just got #10, now I need #11.

Source Source De Dest. st. Seq. Ack. 1028

23

10

1 Source Source Des Dest. t. Seq. Ack. 23 1028 1 11

ZTE University

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TCP Sequence and Acknowledgment Acknowledgment Numbers

Source Port

Dest. Port

Sequence #

Acknowledgement #

I just sent #1 # 11.

…

I just got #10, now I need #11.

Source Source De Dest. st. Seq. Ack. 1028

23

10

1 Source Source Des Dest. t. Seq. Ack. 23 1028 1 11

Source Source De Dest. st. Seq. Ack. 1028

23

ZTE University

11

2

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TCP Sequence and Acknowledgment Acknowledgment Numbers

Source Port

Dest. Port

Sequence #

Acknowledgement #

I just sent #1 # 11.

…

I just got #11, now I need #12.

Source Source De Dest. st. Seq. Ack. 1028

23

10

100 Source Source Des Dest. t. Seq. Ack. 23 1028 100 11

Source Source De Dest. st. Seq. Ack. 1028

23

ZTE University

11

101

Source Source Des Dest. t. Seq. Ack. 23 1028 101 12

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TCP Windo Windowing wing

Sender

ZTE University

Receiver

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TCP Windo Windowing wing

size = 3 Sender Window Send 1

Receiver

Window size = 3 Send 2 Window size = 3 Send 3

ZTE University

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TCP Windo Windowing wing

size = 3 Sender Window Send 1

Receiver

Window size = 3 Send 2 Window size = 3 Send 3

ZTE University

ACK 3 Window size = 2

Packet 3 is Dropped

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TCP Windo Windowing wing

size = 3 Sender Window Send 1

Receiver

Window size = 3 Send 2 Window size = 3 Send 3

ACK 3 Window size = 2

Packet 3 is Dropped

Window size = 3 Send 3 Window size = 3 Send 4

ZTE University

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TCP Windo Windowing wing

size = 3 Sender Window Send 1

Window size = 3

Receiver

Window size = 3 Send 2 Window size = 3 Send 3

Packet 3 is ACK 3 Window size = 2 Dropped

Window size = 3 Send 3 Window size = 3 Send 4 ACK 5 Window size = 2

ZTE University

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UDP Segment Format

Bit 1 0

Bit 15 Bi B i t 16

Bit 31 Destination port (16)

Source port (16) Length (16)

Checksum (16)

8 Bytes

Data (if any)

•

No sequence or acknowledgment acknowledgment fields

ZTE University

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Internet Layer Overview

Internet Protocol (IP) Application

Internet Control Message Protocol (ICMP)

Transport

Address Resolution Protocol (ARP)

Internet Data Link

Reverse Address Resolution Protocol (RARP) (RARP)

Physical

•

ZTE University

OSI network layer corresponds to the TCP/IP internet layer

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IP Datagram Bit 1 0 Version (4)

Bit 15 Bi B i t 16 Header Length (4)

Priority Priori ty & Type of Service (8)

Total Length (16) Flags (3)

Identification (16) Time to live (8)

Bit 31

Protocol (8)

Fragment offset (13) Header checksum (16)

20 Bytes

Source IP Address (32) Destination IP Address (32) Options (0 or 32 if any) Data (varies if any) ZTE University

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Protocol Field

Transport Layer

UDP

TCP 6

17

Internet Layer

•

Protocol Numbers

IP

Determines destination upper-layer protocol

ZTE University

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Internet Control Message Protocol

Application

Destination Unreachable

Transport

1 ICMP

Echo (Ping) Internet

Other Data Link Physical

ZTE University

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Address Resolution Protocol

I need the Ethernet address of 176.16.3.2. 172.16.3.1

172.16.3.2

IP: 172.16.3.2 = ???

ZTE University

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Address Resolution Protocol

I need the Ethernet address of 176.16.3.2.

I heard that broadcast. The message is for me. Here is my Ethernet address. 172.16.3.1

172.16.3.2

IP: 172.16.3.2 = ???

ZTE University

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Address Resolution Protocol

I need the Ethernet address of 176.16.3.2.

I heard that broadcast. The message is for me. Here is my Ethernet address. 172.16.3.1

172.16.3.2

IP: 172.16.3.2 = ??? IP: 172.16.3.2 Ethernet: 0800.0020.1111

ZTE University

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Address Resolution Protocol

I need the Ethernet address of 176.16.3.2.

I heard that broadcast. The message is for me. Here is my Ethernet address. 172.16.3.1

172.16.3.2

IP: 172.16.3.2 = ??? IP: 172.16.3.2 Ethernet: 0800.0020.1111

Map IP ZTE University

MAC Local ARP

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Reverse ARP

What is my IP address?

Ethernet: 0800.0020.1111 IP = ???

ZTE University

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Reverse ARP

I heard that broadcast. Your IP address is 172.16.3.25.

What is my IP address?

Ethernet: 0800.0020.1111 IP = ???

ZTE University

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Reverse ARP

I heard that broadcast. Your IP address is 172.16.3.25.

What is my IP address?

Ethernet: 0800.0020.1111 IP = ??? Ethernet: 0800.0020.1111 IP: 172.16.3.25

ZTE University

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Reverse ARP

I heard that broadcast. Your IP address is 172.16.3.25.

What is my IP address?

Ethernet: 0800.0020.1111 IP = ??? Ethernet: 0800.0020.1111 IP: 172.16.3.25 •

ZTE University

Map MAC

IP

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Introduction to TCP/IP Addresses

172.16.0.1

172.18.0.1 172.18.0.2 10.13.0.0 10.13.0.1

HDR SADA DATA

172.17.0.1

172.16.0.2

172.17.0.2

192.168.1.0 192.168.1.1

Unique addressing allows communication between end stations

–

–

ZTE University

Path choice is based on destination address

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IP Addressing 32 bits Dotted Decimal Maximum

ZTE University

Network

255

Host

255

25 5

25 5

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IP Addressing 32 bits Dotted Decimal

Network

1

Binary

255

255

Maximum

Host

25 5 16 17

8 9

11111111 11111111

25 5 24 25

32

11111111 11111111

       4         2         6 8 4 2 1        4         2         6 8 4 2 1         8         8        4         2         6 8 4 2 1         8        4         2         6 8 4 2 1         8         2         6         3        1         2         6         3        1         2         6         3        1         2         6         3        1        1        1        1        1

ZTE University

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IP Addressing 32 bits Dotted Decimal

Network

1

Binary

255

255

Maximum

Host

2 55 16 17

8 9

11111111 11111111

2 55 24 2 5

32

11111111 11111111

       4         2         6 8 4 2 1        4         2         6 8 4 2 1         8         8        4         2         6 8 4 2 1         8        4         2         6 8 4 2 1         8         2         6         3        1         2         6         3        1         2         6         3        1         2         6         3        1        1        1        1        1

Example Decimal

172

16

1 22

204

Example 101 0101 0110 100 0 00 0001 0100 000 00 01111010 11001100 Binary

ZTE University

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IP Address Classes

8 bits

8 bits

8 bits

8 bits

Host

Host

Host

Host

Host

•

Class A:

Network

•

Class B:

Netwo worrk Netwo worrk

•

Class C:

Network Network Network

•

Class D:

•

Class E:

ZTE University

Host

Multicast Research

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IP Address Classes

Bits:

Class A: Bits:

Class B: Bits:

Class C: Bits:

Class D: ZTE University

1

8 9

0NNNNNNN

16 1 7

24 25

Host

Host

32 Host

Range (1-126) 1

8 9

10N 10 NNNNNN

16 1 7 Network

Range (128-191) 1 8 9 110 10N NNNNN

24 2 5 Host

16 17 Network

Range (192-223) 1 8 9

Host

24 25

Network 16 17

32

32 Host

24 25

32

Multic icas astt Grou Group p Mult Multic icas astt Grou Group p Mult Multic icas astt Grou Group p 1110MMMM 1110 MMMM Mult

Range (224-239)

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Host Addresses

172.16.2.2

172.16.3.10

10.1.1.1

10.6.24.2 E1

E0 172.16.2.1

10.250.8.11

172.16.12.12

172.16 Network ZTE University

.

12 . 12 Host

10.180.30.118

Routing Table Network Interface 172.16.0.0

E0

10.0.0.0

E1

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Determining Available Available Host Addresses Network

172

Host

16

0         6        5        4         3         2        1         0 9        1        1        1        1        1        1        1

0 8 7 6 5 4 3 2 1

101 010 0110 100 0 00 0001 0100 000 00 00000000 00000000 0000 00 0000 0000 00 00 0000 0000 0001 01 0000 00 0000 0000 00 00 0000 0000 001 11   .   .   .   .

ZTE University

  .   .

N 1 2 3

  .   .   .

11111111 11111101 11111111 11111110 11111111 11111111

65534 65535 65536 2

2N-2 = 216-2 = 65534

65534

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IP Address Classes Exercise

Address

Class

Network

Host

10.2.1.1 128.63.2.100 201.222.5.64 192.6.141.2 130.113.64.16 256.241.201.10 ZTE University

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IP Address Classes Exercise Answers

Address

Class

10.2.1.1

A

10.0.0.0

0.2.1.1

128.63.2.100

B

128.63.0.0

0.0.2.100

201.222.5.64

C

201.222.5.0

0.0.0.64

192.6.141.2

C

192.6.141.0

0.0.0.2

130.113.64.16

B

130.113.0.0

0.0.64.16

256.241.201.10 ZTE University

Network

Host

Nonexistent

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Addressing without Subnets

172.16 172.16.0. .0.1 1 172.16 172.16.0. .0.2 2 172.16.0.3

172.16 172.16.25 .255.2 5.253 53 172.16 172.16.25 .255.2 5.254 54 …...

172.16.0.0

ZTE University

•

Network 172.16.0.0

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Addressing with Subnets

172.16.3.0

172.16.4.0

172.16.1.0

ZTE University

•

172.16.2.0

Network 172.16.0.0

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Subnet Addressing

172.16.2.200

172.16.2.2

172.16.3.5

172.16.3.1 E1 E0 172.16.2.1

172.16.3.100

172.16.2.160

172.16 Network ZTE University

.

172.16.3.150

2 . 16 0

New Routing Table Network Interface

Host

172.16.0.0

E0

172.16.0.0

E1

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Subnet Addressing

172.16.2.200

172.16.3.5

172.16.3.1 E1 E0 172.16.2.1

172.16.2.2

172.16.3.100

172.16.2.160

172.16 Network ZTE University

.

2 Subnet

172.16.3.150

.

1 60 Host

New Routing Table Network Interface 172.16.2.0

E0

172.16.3.0

E1

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Subnet Mask Network IP Address

172

Host

16

0

Network Default Subnet Mask

8-bit Subnet Mask ZTE University

0 Host

255

255

0

0

255

255

255

0

11111111 11111111 00000000 00000000 Also written as “/16” where 16 represents the number of 1s in the mask. Network Subnet Host

Also written as “/24” where 24 represents the number of 1s in the mask. univ.zte.com.cn

Decimal Equivalents of Bit Patterns 12 8 64

32

16

8

4

2

1

0

0

0

0

0

0

0

0

=

0

1

0

0

0

0

0

0

0

=

12 8

1

1

0

0

0

0

0

0

=

19 2

1

1

1

0

0

0

0

0

=

22 4

1

1

1

1

0

0

0

0

=

24 0

1

1

1

1

1

0

0

0

=

24 8

1

1

1

1

1

1

0

0

=

25 2

1

1

1

1

1

1

1

0

=

254

1

1

1

1

1

1

1

1

=

25 5

ZTE University

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Subnet Mask without Subnets

Network

Host

172.16.2.160

10101100

00010000

00000010

10100000

255.255.0.0

11111111

11111111

00000000

00000000

10101100

00010000

00000000

00000000

172

16

0

0

Network Number •

ZTE University

Subnets not in use—the default

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Subnet Mask with Subnets

Network 172.16.2.160 255.255.255 255.255.255.0 .0

Subnet

Host

10101100

00010000

00000010

10100000

11111111

11111111

11111111

00000000

10101100

00010000

00000010

00000000

        8         2        4         0         8         2        4        5         2         9         2        4        4        5        5        5        1        1         2         2         2         2         2         2

Network Number •

172

16

2

0

Network number extended by eight univ.zte.com.cn bits

ZTE University

Subnet Mask with Subnets (cont.)

Network 172.16.2.160 255.255.255 255.255.255..192

Subnet

Host

10101100

00010000

00000010

10100000

11111111

11111111

11111111

11000000

10101100

00010000

00000010

10000000 10 000000

        8         2        4         0         8         2        4        5         8         2        4         0         8         2        4        5         2         9         2        4        4        5        5        5         2         9         2        4        4        5        5        5        1        1         2         2         2         2         2         2        1        1         2         2         2         2         2         2

Network Number •

172

16

2

128

Network number extended by ten bits univ.zte.com.cn

ZTE University

Subnet Mask Exercise

Address

Subnet Mask

172.16.2.10

255.255.255.0

10.6.24.20

255.255.240.0

10.30.36.12

255.255.255.0

ZTE University

Class

Subnet

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Subnet Mask Exercise Answers

Address

Subnet Mask

Class

Subnet

172.16.2.10

255.255.255.0

B

172.16.2.0

10.6.24.20

255.255.240.0

A

10.6.16.0

10.30.36.12

255.255.255.0

A

10.30.36.0

ZTE University

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Broadcast Addresses

172.16.3.0

172.16.4.0

172.16.1.0 172.16.2.0

172.16.3.255 (Directed broadcast) 255.255.255.255 (Local network broadcast)

ZTE University

172.16.255.255 (All subnets broadcast)

X

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Addressing Summary Example

172.16.2.160

172

16

10101100

00010000

2

1 60

00000010 10100000 Host

1

Mask

255.255.255.192

Subnet 4 Broadcast First Last ZTE University

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Addressing Summary Example

172.16.2.160 255.255.255.192

172

16

10101100

00010000

11111111

11111111

2

1 60

00000010 10100000 Host

1

11111111 11000000 Mask 2 Subnet Broadcast First Last

ZTE University

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Addressing Summary Example

172

16

2

1 60 3

172.16.2.160 255.255.255.192

10101100

00010000

11111111

11111111

00000010 10100000 Host

1

11111111 11000000 Mask 2 Subnet Broadcast First Last

ZTE University

7

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Addressing Summary Example

172

16

2

1 60 3

172.16.2.160 255.255.255.192

10101100

00010000

11111111

11111111

00000010 10100000 Host

1

11111111 11000000 Mask 2 10000000 Subnet 4 Broadcast First Last

ZTE University

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Addressing Summary Example

172

16

2

1 60 3

172.16.2.160 255.255.255.192

10101100

00010000

11111111

11111111

00000010 10100000 Host

1

11111111 11000000 Mask 2 10000000 Subnet 4

10111111 Broadcast 5 First

6

Last ZTE University

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Addressing Summary Example

172

16

2

1 60 3

172.16.2.160 255.255.255.192

10101100

00010000

11111111

11111111

00000010 10100000 Host

1

11111111 11000000 Mask 2 10000000 Subnet 4

10111111 Broadcast 5 10000001 First

6

Last ZTE University

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Addressing Summary Example

172

16

2

1 60 3

172.16.2.160 255.255.255.192

10101100

00010000

11111111

11111111

00000010 10100000 Host

1

11111111 11000000 Mask 2 10000000 Subnet 4

10111111 Broadcast

ZTE University

5 10000001 First

6

10111110 Last

7

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Addressing Summary Example

172

16

2

1 60 3

10101100

00010000

255.255.255.192 11111111 8

11111111

11111111 11000000 Mask 2

10101100

00010000

00000010 10000000 Subnet 4

10101100

00010000

00000010 10111111 Broadcast

10101100

00010000

5 00000010 10000001 First

6

10101100

00010000

0 0 00 00 1 0

10111110 Last

7

172.16.2.160

ZTE University

00000010 10100000 Host

1

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Addressing Summary Example

172

16

2

1 60 3

10101100

00010000

255.255.255.192 11111111 8 9 172.16.2.128 10101100

11111111

11111111 11000000 Mask 2

00010000

00000010 10000000 Subnet 4

10101100

00010000

00000010 10111111 Broadcast 6

10111110 Last

7

172.16.2.160

172.16.2.191

00000010 10100000 Host

172.16.2.129

10101100

00010000

5 00000010 10000001 First

172.16.2.190

10101100

00010000

0 0 00 00 1 0

ZTE University

1

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Class B Subnet Example IP Hos Hostt Addr Addres ess: s: 17 172. 2.16 16.2 .2.1 .121 21 Subnet Mask: 255.255.255.0 Network

Network

Subnet

Host

172.16.2.121: 10101100

00010000

00000010

01111001

255.255.255.0: 11111111

11111111

11111111

00000000

Subnet: 10101100

00010000

00000010

00000000

Broadcast: 10101100

00010000

00000010

11111111

Subnet Address = 172.16.2.0 Host Addresses = 172.16.2.1 –172.16.2.254 Broadcast Address = 172.16.2.255 Eight bits of subnetting

•

•

•

•

ZTE University

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Subnet Planning

20 subnets 5 hosts per subnet Class C address: 192.168.5.0 192.168.5.16 Other subnets

192.168.5.32

ZTE University

192.168.5.48

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Class C Subnet Planning Example IP Host Host Add Addre ress ss:: 19 192. 2.16 168. 8.5. 5.12 121 1 Subnet Mask: 255.255.255.248 Network

Network

Network Subnet Host

192. 19 2.16 168. 8.5. 5.12 121: 1: 110 1000 0000 000 0

10101000

00000101

01111001

255.255.255.248: 11111111

11111111

11111111

11111000 11111 000

Subnet: 11000000

10101000

00000101

01111000 01111 000

Broadcast: 11000000

1 01 0 1 00 0

00 0 00 1 01

01111111

Subnet Address = 192.168.5.120 192 .168.5.120 Host Addresses Addresses = 192.168.5.121 192.168.5.121 –192.168.5.126 Broadcast Address = 192.168.5.127 192.16 8.5.127 Five Bits of Subnetting

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ZTE University

univ.zte.com.cn

Broadcast Addresses Exercise

Address

Subnet Mask

201.222.10.60

255.255.255.248

15.16.193.6

255.255.248.0

128.16.32.13

255.255.255.252

153.50.6.27

255.255.255.128

ZTE University

Class

Subnet

Broadcast

univ.zte.com.cn

Broadcast Addresses Exercise Answers

Address

Subnet Mask

Class

Subnet

Broadcast

201.222.10.60 255.255.255.248

C

201.222.10.56

201.222.10.63

15.16.193.6

255.255.248.0

A

15.16.192.0

15.16.199.255

128.16.32.13

255.255.255.252

B

128.16.32.12

128.16.32.15

153.50.6.27

255.255.255.128

B

153.50.6.0

153.50.6.127

ZTE University

univ.zte.com.cn

01 Osi Model & Tcpip

Short Description

Description

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