IPUB_102_E1IPUB_102_E1

TCP/IP Basic TheoryTCP/IP Basic Theory

V1.2V1.2

IP D&T GroupIP D&T Group

Gandeva Bayu Satrya

1111 OSI Model and Layer Function

2

TCP/IPTCP/IP

Host A

Internet

Host B

3

• First used protocol suite

• Universal De-facto standard

• Internet standard communication

TCP/IP

OSI ModelOSI Model

Upper Layer

Session

Presentation

Application Layer7

Layer6

Layer5

4

Data Layer

Transport

Data Link

Network

Physical

Layer4

Layer3

Layer2

Layer1

TelnetFTP

ASCII

Example

Upper Layer Function Upper Layer Function

Network User InterfaceApplication

5

ASCIIEBCDICJPEG

Keep different applications independent AuthenticationSession

Presentation • Data Presentation• Encryption, Decryption

TCPUDPSPX

IPIPX

ExampleData Layer FunctionData Layer Function

Transport

Network

• Reliable and Unreliable transfer• Use retransmission to ensure reliability

Provide logical address and path-finding method for the working of routers

6

802.3 / 802.2HDLC

EIA/TIA-232V.35

IPXNetwork

Data Link

Physical

• Combine bit to byte and byte to frame• Access media by MAC address• Error detection without error correction

method for the working of routers

• Transfer bit between devices• Define voltage, bit rate, physical connection

Upper Layer Data

Upper Layer DataTCP Header Segment

PDU

Data EncapsulationData Encapsulation

Transport

Presentation

Application

Session

7

IP Header

0101110101001000010

MAC+LLC Header

Packet

Bits

FrameFCSData Link

Physical

NetworkUpper Layer Data

Upper Layer Data

2222 TCP/IP Protocol Suite

8

Application

Presentation

SessionApplication

TCP/IP Model vs OSI ModelTCP/IP Model vs OSI Model

9

Session

Transport

Network

Data Link

Physical

Application

Transport

Internet

Access Net

FTP

TELNET

DNS

TFTP

SMTP

SNMP

TCP/IP Protocol SuiteTCP/IP Protocol Suite

10

Application

Data Link

TCP

T

UDP

21 23 25 53 69 161

IP176

Application

Transport

Internet

Data Link

ARP ICMP

Ethernet II (RFC 894 )

080008061

11

3333 Transfer Control Protocol

Transport LayerTransport Layer

• Segment upper layer data

• Establish end to end connection

• Ensure the reliability of data transfer

12

Logical connection

TCP ProtocolTCP Protocol

Source Port (16) Destination Port (16)

Sequence Number (32)

Acknowledgement Number (32) 20Bytes

Bit 0 Bit 15 Bit 16 Bit 31

13

HeaderLength (4) Reserved (6) Code Bits (6) Window (16)

Checksum (16) Urgent (16)

Options (0 or 32 if any)

Data (varies)

Bytes

Port Number RangePort Number Range

FTP

TELNET

DNS

TFTP

SMTP

SNMP

14

Well-known Port Number: 0-1023 Common Port Number: 1024-65535

Application

TCP

T

UDP

21 23 25 53 69 161Application

Transport

Application

Transport

Internet

Data Link

Source Port Number

Destination Port Number

client

Telnet ZProcess #1

Port Number FunctionPort Number Function

Destination port = 23Send packet to my

Telnet server

15

client

1028 23

SP DP

Process #1 Telnet application

server

1029 23

Telnet ZProcess #2

Port Multiplexing

Sender Receiver

1 2 3 4 5 6 1 2 3 4 5 6

Sequence and Ack NumberSequence and Ack Number

16

Send 2Send 1

Send 3Ack 4

Send 5Send 4

Send 6Retransfer 5

Send 5Ack 7

1 2 3 4 5 6 1 2 3 4 5 6

Code BitsCode Bits

U

R

G

P

S

H

R

S

T

S

Y

N

F

I

N

A

C

K

17

URG: Urgent Pointer field significant

ACK: Acknowledgment field significant

PSH: Push function

RST: Reset the connection

SYN: Synchronize sequence numbers

FIN: No more data from sender

Window Size = 1

Send 1 Receive 1Ack 2

Send 2 Receive 2Ack 3Sender Receiver

Window ControlWindow Control

18

Send 1

Send 2

Receive 1

Receive 2

Window Size = 3

Send 3 Receive 3

Ack 4

Send 4

Sender Receiver

Sender Receiver

Connection-oriented SessionConnection-oriented Session

TCP connection

19

Establish connection (Synchronize)

Data Transfer (Send Segments)

Sender Receiver

Tear down connection

1

2

3

Establish ConnectionEstablish Connection

TCP Three Way Handshake/Open Connection

Host A Host B

20

Send SYN (seq=100 ctl=SYN) SYN received

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

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

1

2

3

SYN received

Established

Data TransferData Transfer

SP DP Seq. # Ack. #

Host A Host B

Upper layer data

21

10281028 2323

Source Dest.

103103103103

Seq.

302302

Ack.

10281028 2323Source Dest.

102102102102Seq.

301301Ack.

102810282323Source Dest.

103103103103Seq.301301

Ack.

102810282323Source Dest.

104104104104Seq.302302

Ack.

FINClose application

Host A Host B

Tear Down ConnectionTear Down Connection

TCP four way handshakes/connection termination

1

22

ACK to FIN

ACK to FIN

FIN Close application

1

2

3

4

UDP ProtocolUDP Protocol

Source port (16) Destination port (16)

Length (16)

Bit 0 Bit 15 Bit 16 Bit 31

Checksum (16)

8Bytes

23

Data (if any)

• No sequence and acknowledgement

• Unreliable and connectionless

• Efficient and fast

TCP UDP

Connection oriented Or connectionless

Connection oriented

Connectionless

TCP/UDP ComparisonTCP/UDP Comparison

24

Reliable or not Reliable Unreliable

With traffic Control Or not Traffic control No traffic control

Transfer speed Slow Fast

Overhead of Protocol Big Small

25

4444 Internet Protocol

Define logical address

Provide path-finding method routers

Internet/Network layerInternet/Network layer

26

Data Link

TCP UDP

IP176

Application

Transport

Internet

Data Link

ARP ICMP1

IP Packet FormatIP Packet Format

Version(4)

1Bit 0 Bit 15 Bit 16 Bit 31

HeaderLength (4)

Typeof Service (8) Total Length (16)

Identification (16)Flags

(3) Fragment offset (13)

20

27

Destination IP Address (32)

Options (0 or 32 if any)

Upper layer data (varies if any)

Time to live (8) Protocol (8) Header checksum (16)

Source IP Address (32)

20Bytes

Type of Service FieldType of Service Field

Precedence D T R 0 0

0 3 7

28

Bits 0-2: PrecedenceBit 3: DelayBit 4: ThroughputBit 5: ReliabilityBits 6-7: Reserved for future use

IP AddressIP Address

Host A Host B

172.16.2.1 10.250.8.11172.16.2.1 10.6.24.2

Fei_1/1 Fei_1/2

0 7 8 15 16 23 24 31

29

255 255 255

DottedDecimal

Maximum

Network Host

255

128 64 32 16 8 4 2 1

11111111 11111111 11111111 11111111Binary

0 7 8 15 16 23 24 31

128 64 32 16 8 4 2 1

128 64 32 16 8 4 2 1

128 64 32 16 8 4 2 1

ICMPICMP

Application

30

Data LinkIP

Transport

Internet

Data Link

ICMP1

Host A I am here.

ICMP echo reply

Hi B, are you there?

Host B

Ping and ReachabilityPing and Reachability

31

ICMP echo request

Host or port unreachable

Network unreachable

Destination Unreachable

Is B reachable?

ICMP echo request

no yes

Time Exceeded and TTLTime Exceeded and TTL

Host A Host B

A: Tracert 10.1.1.2

1: 172.16.1.1

2: 200.1.1.2

3: 10.1.1.210.1.1.1172.16.1.1

32

10.1.1.2

10.1.1.1

200.1.1.1200.1.1.2

172.16.1.2

172.16.1.1

RA RB

TTL=1

TTL=2

TTL=3

Combine bit to byte and byte to frame

Access media by physical address (MAC address)

SAP associated with upper layer protocols type

Data Link LayerData Link Layer

Application

33

SAP associated with upper layer protocols type

Error detection without error correction

Data LinkIP

Application

Transport

Internet

Data Link

ARP ICMP

Ethernet II (RFC 894 )

080008061

DataSrc. Addr FCSTypeDest. Addr

Variable Length46-1500266 4

Ethernet II frame (RFC 894)

Preamble

8# Bytes

48-bits MAC Address48-bits MAC Address

34

DataSrc. Addr FCSDest. Addr

00.d0.d0 xx.xx.xx

Sequence ID for NICIEEE assign toManufacturers

Address Resolution ProtocolAddress Resolution Protocol

I got the packet,I will reply with my MAC address.

I need the MAC address of IP 172.16.3.2

Host A Host B

35

• Map IP to MAC

• Local broadcast

IP: 172.16.3.2 Ethernet: 0800.0020.1111

172.16.3.1 172.16.3.2

IP: 172.16.3.2 = ???Other hosts

Packet Process ProcedurePacket Process Procedure

FTP client FTP server

36

ftp://10.66.1.100:21 I want to download a file

SP:1024 DP:21 Seq.100 Ack.200

SIP:10.66.1.1 DIP:10.66.1.100,TTL=100, DF, Protocol=7

SA:01-00-39 DA:01-00-4A type=0800

01010010100010101010101010100010110111000101001

5555 IP Address Classification

37

5555 IP Address Classification

IPv4 Address FunctionIPv4 Address Function

SADAHDR DATA10.13.0.1 192.168.1.1

38

172.17.0.2172.17.0.1

• Uniquely and logically identify end stations

• Packet forwarding is based on IP Address

ClassificationClassification

• Class A:

• Class B:

Network Host Host Host

Network Network Host Host

8 bits 8 bits 8 bits 8 bits

39

• Class C:

• Class D: Multicast Address

• Class E: Reserved for Research

Network Network Host Host

Network Network Network Host

1

Class A:Bits:

0NNNNNNN Host Host Host

8 9 16 17 24 25 32

Range (1-126)

Class B: 10NNNNNN Network Host Host

Possible Valid Network NumbersPossible Valid Network Numbers

40

Class B: 10NNNNNN Network Host Host

Range (128-191)

Class C: 110NNNNN Network Network Host

Range (192-223)

Class D: 1110MMMM Multicast Group Multicast Group Multicast Group

Range (224-239)

6666 Subnet and IP Address Calculation

41

6666 Subnet and IP Address Calculation

Addressing Without SubnetsAddressing Without Subnets

172.19.0.0

172.18.0.0AA

42

172.16.0.0 172.17.2.0

172.18.0.0

Subnet mask: 255.255.0.0

AA

BB

Addressing With SubnetsAddressing With Subnets

172.16.3.0

172.16.4.0AA

43

172.16.1.0 172.16.2.0

172.16.4.0

Subnet mask: 255.255.255.0

AA

BB

Subnet Mask And PrefixSubnet Mask And Prefix

172172 1616 00 00

Network Host

Network Host

Address

Default

44

255 255 0 0

255255 255255 255255 00

Subnet Host

11111111 11111111 00000000 00000000

Network Host

Network

Also written as “ /16” where 16 represents the number of 1s in the mask.

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

DefaultSubnetMask

8-bits subnetMask

Address Formats When SubnettingAddress Formats When Subnetting

Network Subnet Host

Network Subnet Host

Class A:

Class B:

8 24-x x

16 16-x x

x8-x

45

SubnetNetwork HostClass C:

x24 8-x

172.16 2 160

Network Host

. .

Subnet

. .255.255 255 0

How Many Hosts And SubnetsHow Many Hosts And Subnets

Process:

Step 1:The class rules define the network part.

Step 2:The mask binary 0s define the host part.

Step 3:What’s left over defines the size of subnet part

46

Step 3:What’s left over defines the size of subnet part

Step 4:Number of subnets= 2number-of-subnet-bits -2

Step 5:Number of hosts per subnet =2number-of-host-bits -2

Broadcast Address ExerciseBroadcast Address Exercise

Address Class Subnet Broadcast

201.222.10.60 255.255.255.248

Subnet Mask

47

15.16.193.6 255.255.248.0

128.16.32.13 255.255.255.252

153.50.6.27 255.255.255.128

48

7777 VLSM

172.16.14.32/27

172.16.14.64/27

AA

Variable Length Subnet MaskVariable Length Subnet Mask

49

CC

172.16.14.96/27

HQHQHQHQBB

Derived from

172.16.0.0/16

Derived from

172.16.14.0/24

Derived from

172.16.14.128/27

CC

Subnetted Address: 172.16.14.0/24In Binary 10101100. 00010000.00001110.00000000

VLSM Address: 172.16.14.0/27In Binary 10101100. 00010000.00100000.000 00000

001 00000010 00000011 00000

172.16.14.32/27172.16.14.64/27172.16.14.96/27172.16.14.128/27

VLSM CalculationVLSM Calculation

50

011 00000100 00000

172.16.14.96/27172.16.14.128/27

VLSM Address: 172.16.14.128/27In Binary 10101100. 00010000.00100000.10000000

00100010000110010000

172.16.14.132/30172.16.14.136/30172.16.14.140/30

VLSM Subnet

VLSM Subnet

51

8888 VLAN

Hub : Works at the Physical LayerHub : Works at the Physical Layer

A B C D

• All the devices in one collision domain

• All the devices in one broadcast domain

• All the devices share the same bandwidth

Switch: Works At Data Link LayerSwitch: Works At Data Link Layer

1 2 3 4

• Each segment is a single collision domain

• All segments are in one broadcast domain

Broadcast StormBroadcast Storm

ENG Dept.

HR Dept.

SALES Dept.

Broadcast Frame

Isolation - Physically Isolation - Physically

ENG Dept.HR Dept.

SALES Dept.

VLAN - Logical IsolationVLAN - Logical Isolation

Broadcast Domain 1Broadcast Domain 1VLAN 10VLAN 10 Broadcast Domain 2Broadcast Domain 2

VLAN 20VLAN 20

Broadcast Domain 3Broadcast Domain 3VLAN 30VLAN 30

Port-based

1 VLAN = 1 Broadcast Domain = Logical Network (Subnet)

VLAN 20VLAN 20

HR Dept.

SALES Dept.ENG Dept.

3rd floor

VLAN AdvantagesVLAN Advantages

• Segmentation

• Flexibility

2nd floor

1st floor

SALES HR ENG

• Flexibility

• Security

9999 Basic Concepts Routing9999 Basic Concepts Routing

DefinitionDefinition

• Router - a computer device used to interconnect network

• Router must have the following features:

• Multiple three layer interfaces to interconnect different • Multiple three layer interfaces to interconnect different networks

• Implement the protocol up to the network layer

• Have the function of storing, forwarding, path-finding

Basic ConceptsBasic Concepts

• Routed Protocol

• Routing Protocol

• Route Types• Route Types

• Connected Route

• Static Route

• Dynamic Route

• Default Route

172.16.2.010.120.2.0

E0S0

Routing Protocol and Routed ProtocolRouting Protocol and Routed Protocol

NetworkProtocol

DestinationNetwork

ConnectedRIP

OSPF

10.120.2.0172.16.2.0172.17.3.0

Exit Interface

fei_0/1e1_1e1_2

Routed Protocol: IPRouting Protocol: RIP, OSPF

172.17.3.0

Routing TableRouting Table

• The information that a router needs to forward is stored in a table, called “routing table”.

• Routers check the destination address of the packet, and choose the next hop based on the information in the routing table.the next hop based on the information in the routing table.

• Route table is stored in RAM.

Routing Table CompositionRouting Table Composition

• Destination Address

• Mask

• Next Hop Address (Gateway)

• Forwarding Physical Interface• Forwarding Physical Interface

• Source of the Information (Owner)

• Route Priority

• Metric

Routing Table CompositionRouting Table Composition

Example

172.16.8.0 : Destination network address

Dest Mask Gw Interface Owner Pri Metric

172.16.8.0 255.255.255.0 1.1.1.1 fei_0/1.1 static 1 0

172.16.8.0 : Destination network address

255.255.255.0 : Destination network mask

1.1.1.1 : Next hop address

fei_0/1.1 : Route learning interface and forwarding interface

Static : How does router learns this entry

1 : Route Priority

0 : Metric

Route TypesRoute Types

Default Route Directly Connected Route

Static Route Dynamic Route

192.168.0.1/30192.168.0.1/30192.168.0.1/30192.168.0.1/30

192.168.0.2/30192.168.0.2/30192.168.0.2/30192.168.0.2/30

10.0.0.1/2410.0.0.1/2410.0.0.1/2410.0.0.1/24

172.16.0.1/24172.16.0.1/24172.16.0.1/24172.16.0.1/24

IPv4 Routing TableDest Mask Gw Interface Owner Pri Metric

Directly Connected RouteDirectly Connected Route

BA

10.0.0.0 255.255.255.0 10.0.0.1 fei_0/1 direct 0 010.0.0.1 255.255.255.255 10.0.0.1 fei_0/1 address 0 0192.168.0.0 255.255.255.252 192.168.0.1 fei_1/1 direct 0 0192.168.0.1 255.255.255.255 192.168.0.1 fei_1/1 address 0 0ZXR10#

When network address is configured and the status of the interface is valid, the network configured on this network will appear in the route table and associated with this interface，the route will change with the status of the interface.

Static Route ConfigurationStatic Route ConfigurationStub Network

172.16.2.1

SO

172.16.1.0

B172.16.2.2Network

10.0.0.0B A

ip route 10.0.0.0 255.0.0.0 172.16.2.2

172.16.2.1B

172.16.2.2NetworkB A

This is a unidirectional route, there should be an opposite route configured on the counterpart router.

Example

Default Route ConfigurationDefault Route Configuration

Stub Network

SO

172.16.1.0

Network A B

ip route 0.0.0.0 0.0.0.0 172.16.2.2

172.16.2.1172.16.2.2Network A B

Default route is configured on the egress router in a stub network.

RIPOSPF RIPOSPF

1.0.0.0/8 2.0.0.0/8 3.0.0.0/8

Dynamic RouteDynamic Route

Routing protocol is a software process running on the router. It willexchange routing information with other routers ， studying routeinformation of network not directly connected and adjusting the routeinformation when topology changes.

Longest Match PrincipleLongest Match Principle

ZXR10#show ip routeIPv4 Routing Table:Dest Mask Gw Interface Owner Pri Metric

1.0.0.0 255.0.0.0 1.1.1.1 fei_1/1.1 direct 0 01.1.1.1 255.255.255.255 1.1.1.1 fei_1/1.1 address 0 0

10.1.1.1→?

1.1.1.1 255.255.255.255 1.1.1.1 fei_1/1.1 address 0 02.0.0.0 255.0.0.0 2.1.1.1 fei_1/1.2 direct 0 02.1.1.1 255.255.255.255 2.1.1.1 fei_1/1.2 address 0 03.0.0.0 255.0.0.0 3.1.1.1 fei_1/1.3 direct 0 03.1.1.1 255.255.255.255 3.1.1.1 fei_1/1.3 address 0 010.0.0.0 255.0.0.0 1.1.1.1 fei_1/1.1 ospf 110 1010.1.0.0 255.255.0.0 2.1.1.1 fei_1/1.2 static 1 010.1.1.0 255.255.255.0 3.1.1.1 fei_1/1.3 rip 120 50.0.0.0 0.0.0.0 1.1.1.1 fei_1/1.1 static 0 0

Communication ProcessCommunication Process

IP address：192.168.1.2MAC address：00:20:AF:00:00:02

IP address：192.168.1.1MAC address：00:20:AF:00:00:01

No need to consider

A BNetwork

Hub

Ethernet

IP layer

No need to consider higher layer protocols

Encapsulate IP address in

packet and send to 192.168.1.2

Ethernet

IP layer

Encapsulate MAC address in frameand send to MAC

address00:20:AF:00:00:02

Decapsulate MAC frameReceiving

MAC frame

ARP

decapsulateIP packetReceiving IP packet

Protocol Layer

Communication between Different NetworkCommunication between Different NetworkNetwork

Protocol

Ethernet

PPP

HOST A HOST B

fei-1/1 e1_2/1.1Ethernet

fei-1/1e1_2/1.1

No need to consider higher layer protocols

No need to consider higher layer protocols

EthernetEthernetinterface

Ethernet

IP Layer

MAC Frame

IP Layer

Serial interface

Ethernetinterface

IP Layer

PPP Packet

IP Packet

IP Packet

Send host A

Receiving host B

Router

IP Layer

Router

PPP Frame

IP Packet

Serial interface

MAC Frame

IP Packet

IP Packet

IP Packet

Network Protocol Layer ProcessNetwork Protocol Layer Process

XY

AA

CC

ApplicationPresentationSessionTransportNetworkData LinkPhysical

ApplicationPresentationSessionTransportNetworkData LinkPhysical

A B C

X Y

NetworkData LinkPhysical

NetworkData LinkPhysical

NetworkData LinkPhysical

BB

Routing Process ExampleRouting Process Example

192.168.6.0 /24e1_1/1.1

192.168.1.0 /24

R2

R1 route tableR1 route tableR1 route tableR1 route table192.168.4.0 255.255.255.0 192.168.4.1 e1_1/1.1 direct 0 0 192.168.4.0 255.255.255.0 192.168.4.1 e1_1/1.1 direct 0 0 192.168.4.0 255.255.255.0 192.168.4.1 e1_1/1.1 direct 0 0 192.168.4.0 255.255.255.0 192.168.4.1 e1_1/1.1 direct 0 0 192.168.2.0 255.255.255.0 192.168.2.1 fei_1/1 direct 0 0192.168.2.0 255.255.255.0 192.168.2.1 fei_1/1 direct 0 0192.168.2.0 255.255.255.0 192.168.2.1 fei_1/1 direct 0 0192.168.2.0 255.255.255.0 192.168.2.1 fei_1/1 direct 0 0192.168.1.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 1192.168.1.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 1192.168.1.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 1192.168.1.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 1192.168.6.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 1 192.168.6.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 1 192.168.6.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 1 192.168.6.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 1 192.168.3.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 2192.168.3.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 2192.168.3.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 2192.168.3.0 255.255.255.0 192.168.4.2 e1_1/1.1 rip 120 2

e1_2/1.1

fei_1/1

192.168.6.0 /24

192.168.2.0 /24

e1_1/1.1

fei_1/1

192.168.2.3

192.168.3.0 /24

192.168.3.3

192.168.4.0 /24

R1R3

e1_1/1.1

fei_1/1Destination address:Destination address:Destination address:Destination address:

192.168.3.3192.168.3.3192.168.3.3192.168.3.3

A B

Routing Process ExampleRouting Process Example

192.168.6.0 /24

192.168.1.0 /24

192.168.4.0 /24

R2

R2 route tableR2 route tableR2 route tableR2 route table192.168.4.0 255.255.255.0 192.168.4.2 e1_1/1.1 direct 0 0 192.168.4.0 255.255.255.0 192.168.4.2 e1_1/1.1 direct 0 0 192.168.4.0 255.255.255.0 192.168.4.2 e1_1/1.1 direct 0 0 192.168.4.0 255.255.255.0 192.168.4.2 e1_1/1.1 direct 0 0 192.168.6.0 255.255.255.0 192.168.6.1 e1_2/1.1 direct 0 0192.168.6.0 255.255.255.0 192.168.6.1 e1_2/1.1 direct 0 0192.168.6.0 255.255.255.0 192.168.6.1 e1_2/1.1 direct 0 0192.168.6.0 255.255.255.0 192.168.6.1 e1_2/1.1 direct 0 0192.168.1.0 255.255.255.0 192.168.1.1 fei_1/1 direct 0 0192.168.1.0 255.255.255.0 192.168.1.1 fei_1/1 direct 0 0192.168.1.0 255.255.255.0 192.168.1.1 fei_1/1 direct 0 0192.168.1.0 255.255.255.0 192.168.1.1 fei_1/1 direct 0 0192.168.2.0 255.255.255.0 192.168.4.1 e1_1/1.1 rip 120 1192.168.2.0 255.255.255.0 192.168.4.1 e1_1/1.1 rip 120 1192.168.2.0 255.255.255.0 192.168.4.1 e1_1/1.1 rip 120 1192.168.2.0 255.255.255.0 192.168.4.1 e1_1/1.1 rip 120 1192.168.3.0 255.255.255.0 192.168.6.2 e1_1/1.1 rip 120 1192.168.3.0 255.255.255.0 192.168.6.2 e1_1/1.1 rip 120 1192.168.3.0 255.255.255.0 192.168.6.2 e1_1/1.1 rip 120 1192.168.3.0 255.255.255.0 192.168.6.2 e1_1/1.1 rip 120 1

e1_1/1.1 e1_2/1.1

fei_1/1

1.Destination address:192.168.3.31.Destination address:192.168.3.31.Destination address:192.168.3.31.Destination address:192.168.3.3

192.168.6.0 /24

192.168.2.0 /24

192.168.2.3

192.168.3.0 /24

192.168.3.3

192.168.4.0 /24

R1R3

e1_1/1.1

fei_1/1

e1_1/1.1

fei_1/1

Destination Address:Destination Address:Destination Address:Destination Address:192.168.3.3192.168.3.3192.168.3.3192.168.3.3

192.168.6.0 /24

192.168.1.0 /24

192.168.4.0 /24

R2

R3 route tableR3 route tableR3 route tableR3 route table192.168.3.0 255.255.255.0 192.168.3.1 fei_1/1 direct 0 0192.168.3.0 255.255.255.0 192.168.3.1 fei_1/1 direct 0 0192.168.3.0 255.255.255.0 192.168.3.1 fei_1/1 direct 0 0192.168.3.0 255.255.255.0 192.168.3.1 fei_1/1 direct 0 0192.168.6.0 255.255.255.0 192.168.6.2 e1_1/1.1 direct 0 0192.168.6.0 255.255.255.0 192.168.6.2 e1_1/1.1 direct 0 0192.168.6.0 255.255.255.0 192.168.6.2 e1_1/1.1 direct 0 0192.168.6.0 255.255.255.0 192.168.6.2 e1_1/1.1 direct 0 0192.168.1.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 1192.168.1.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 1192.168.1.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 1192.168.1.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 1192.168.4.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 1192.168.4.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 1192.168.4.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 1192.168.4.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 1192.168.2.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 2192.168.2.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 2192.168.2.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 2192.168.2.0 255.255.255.0 192.168.6.1 e1_1/1.1 rip 120 2

e1_1/1.1 e1_2/1.1

fei_1/1

Routing Process ExampleRouting Process Example

192.168.2.0 /24

192.168.2.3

192.168.3.0 /24

192.168.3.3

R1R3

e1_1/1.1

fei_1/1

e1_1/1.1

fei_1/1

Destination address:Destination address:Destination address:Destination address:192.168.3.3192.168.3.3192.168.3.3192.168.3.3

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