IP Routing

Jaringan Komputer IE 3713

Program Studi Teknik Industri

Fakultas Rekayasa Industri IT Telkom

1 Computer Network - Industrial Engineering -

Faculty of Industrial Engineering

Routing

Routing adalah proses pengiriman informasi/data padanetwork dari pengirim ke penerima pada network yang berbeda (melalui internetworking)

Untuk dapat merutekan paket, diperlukan Router

Untuk dapat merutekan paket, Router setidaknya harusmengetahui Address (IP) Penerima

Router yang bertetangga,

Rute/track yang dapat di bypass (dilewati)

Rute terbaik dari masing-masing network

Informasi Routing

2

Routing

Routing adalah suatu protokol yang digunakan

untuk mendapatkan rute dari satu jaringan ke

jaringan yang lain.

Rute ini, disebut dengan route dan informasi

route secara dinamis dapat diberikan ke router

yang lain ataupun dapat diberikan secara statis

ke router lain

Routing adalah proses dimana suatu router

mem-forward paket ke jaringan yang dituju

3

Routing Proses

ping 172.16.100.15 dari 172.16.20.154

172.16.20.15

A

172.16.100.15

B

E0:172.16.20.1

E1:172.16.100.1

Routing Proses

Paket dibuat di kom A dan akan dikirim ke kom B

A membroadcast ARP ke network untuk mengetahui MAC address B

Ketika B berlokasi di network yang berbeda, Router memberirespon dengan menyediakan alamat fisik, jadi paket dikirim langsung ke router (sebagai default router)

A mengirim paket ke router melalui port E0

Alamat hardware yang sesuai dengan router HA, kemudianheader frame dibuang, tinggal paket IP. Router kemudianmengecek alamat penerima. Ketika router mengetahui bahwa penerima adalah 172.16.100.15,Router tahu (dari tabel routing) bahwa alamat 172.16.100.0 network dapat mencapai dan menyelesaikannya melalui port E1.

5

Routing Process

Router menyerahkan paket ke port E1.

Kemudian dari E1 dikirim ke B

Paket diterima oleh B dan kemudian

diproses untuk melihat kontennya

Karena paket adalah sebuah ping

(ICMP), B menjawab paket tersebut

(membalas) ke A. Prosesnya sama

dengan sebelumnya hanya arah saja

yang berbeda. 6

Tipe Routing

Static Routing, admin mengset secara manual

routing tabelnya.

Default Routing, digunakan untuk merutekan

paket dengan tujuan yang tidak sama dengan

routing yang ada dalam tabel routing.

Dynamic Routing, router-router m engikuti

aturan yang didefinisikan oleh protokol routing

untuk pertukaran informasi routing dan

pemilihan jalur terbaik

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Routing on the network

8

2621A

2501A

2501B

2501C

F0/0

10.1

E0

10.2

S0

20.1

S0

20.2

30.1

E0

S1

40.1

S0

40.2 E0

50.1

Router NA Port HA

2621A 172.16.10.0 F0/0 172.16.10.1

2501A 172.16.10.0 E0 172.16.10.2

2501A 172.16.20.0 S0 172.16.20.1

2501B 172.16.20.0 S0 172.16.20.2

172.16.10.0

172.16.20.0

172.16.30.0

172.16.40.0 172.16.50.0

Router NA Port HA

2501B 172.16.30.0 E0 172.16.30.1

2501B 172.16.40.0 S1 172.16.40.1

2501C 172.16.40.0 S0 172.16.40.2

2501C 172.16.50.0 E0 172.16.50.1

Static Routing

Tidak ada beban di CPU

Tidak memerlukan komunikasi antar router

Ketika menggunakan routing statis, seorang network administrator mengkonfigurasi informasi tentangjaringan yang ingin dituju secara manual.

Jika routing yang digunakan adalah statis, makakonfigurasinya harus dilakukan secara manual, administrator jaringan harus memasukkan ataumenghapus rute statis jika terjadi perubahan topologi

Pada jaringan skala besar, jika tetap menggunakanrouting statis, maka akan sangat membuang waktuadministrator jaringan untuk melakukan update table routing 9

Static Routing

Router 2621A terkoneksi langsung hanya

dengan network 172.16.10.0. Dengan

network lain harus dikonfigurasi

Routing tabel untuk 2621A

10

C = connected, S = static

Network Number Next Hope/Port Keterangan

172.16.50.0 172.16.10.2 S

172.16.40.0 172.16.10.2 S

172.16.30.0 172.16.10.2 S

172.16.20.0 172.16.10.2 S

172.16.10.0 F0/0 C

Static Routing

2501A router terkoneksi langsung ke

network 172.16.10.0 dan 172.16.20.0. Dengan network lain harus di konfigurasi

Bagaimana routing tabel dari 2501A?

11

Jawaban

Network Number Next Hope/Port Keterangan

172.16.50.0 172.16.20.2 S

172.16.40.0 172.16.20.2 S

172.16.30.0 172.16.20.2 S

172.16.20.0 S0 C

172.16.10.0 E0 C

Static Routing

Dengan cara yang sama, bagaimanakonfigurasi dari router 2501B dan 2501C ?

13

Jawaban

2501B

NN NH/Port Ket

172.16.50.0 172.16.40.2 S

172.16.40.0 S1 C

172.16.30.0 E0 C

172.16.20.0 S0 C

172.16.10.0 172.16.20.1 S

2501C

NN NH/Port Ket

172.16.50.0 E0 C

172.16.40.0 S0 C

172.16.30.0 172.16.40.1 S

172.16.20.0 172.16.40.1 S

172.16.10.0 172.16.40.1 S

Static Routing

Cara kerja routing statis dapat dibagi

menjadi 3 bagian:

Administrator jaringan yang

mengkonfigurasi router

Router melakukan routing

berdasarkan informasi dalam tabel

routing

Routing statis digunakan untuk

melewatkan paket data

Kelebihan dan Kekurangan

Static Routing

Kekurangan Kelebihan

Konfigurasi perawatan

yang sangat tinggi

Overhead prosesor rendah

Tidak dapat disesuaikan. Tidak ada penggunaan

Bandwidth

Secure Operational

Terprediksi

Default Routing

Pada Routing tabel, default routing adalah

pada NN yang terhubung langsung ke Router

Contoh

17

2501B

NN NH/Port Ket

172.16.50.0 172.16.40.2 S

172.16.40.0 S1 C

172.16.30.0 E0 C

172.16.20.0 S0 C

172.16.10.0 172.16.20.1 S

Default

Routing

Default Routing

Bagiamana dengan Router 2501C

Jawaban

2501C

NN NH/Port Ket

172.16.50.0 E0 C

172.16.40.0 S0 C

172.16.30.0 172.16.40.2 S

172.16.20.0 172.16.40.2 S

172.16.10.0 172.16.40.2 S

Dynamic Routing

Routing protocol adalah komunikasi antararouter-router. Routing protocol mengijinkanrouter-router untuk sharing informasitentang jaringan dan koneksi antar router. Router menggunakan informasi ini untukmembangun dan memperbaiki tabelroutingnya.

Tipe dari Dynamic Routing RIP (Routing Information Protocol)

IGRP (Interior Gateway Routing Protocol)

EIGRP (Enhanced IGRP)

OSPF (Open Shortest Path First)20

Administrative Distance

Level digit dari informasi routing yang harus dapatdipercaya.

Nilainya antara 0 -255, 0 adalah angka yang dapatdipercaya, ketika 255 mengidentifikasikan bahwatidak akan ada lagi trafik yang dapat melewati route

Tabel Administrative Distance oleh Cisco

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Route

Source

Default

Distance

Langsung 0

Static 1

EIGRP 90

IGRP 100

Route Source Default

Distance

OSPF 110

RIP 120

External EIGRP 170

Unknown 255

Routing Protocol

Sebagian besar algoritma routing

dapat diklasifikasikan menjadi dua

kategori berikut:

Distance Vector, using the distance

(Distance) to determine the best path

to a remote network

link state

Hybrid22

Distance Vector

Routing distance vector bertujuan untuk

menentukan arah atau vector dan jarak

ke link-link lain dalam suatu internetwork

Masing2 node(router) membuat vektor

(Destination, cost, Next Hope) untuk

semua node.

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Distance Vector

24

A

Dest Cost Next

1.0 0 --

2.0 0 --

D

Dest Cost Next

3.0 0 --

5.0 0 --

6.0 0 --

C

Dest Cost Next

2.0 0 --

3.0 0 --

B

Dest Cost Next

4.0 0 --

5.0 0 --

A

Dest Cost Next

1.0 0 --

2.0 0 --

3.0 1 C=2.2

D

Dest Cost Next

3.0 0 --

5.0 0 --

6.0 0 --

2.0 1 C=3.1

4.0 1 B=5.2

C

Dest Cost Next

2.0 0 --

3.0 0 --

1.0 1 A=2.1

5.0 1 D=3.2

6.0 1 D=3.2

B

Dest Cost Next

4.0 0 --

5.0 0 --

3.0 1 D=5.1

6.0 1 D=5.1

5.12.2

4.1

5.2

1.1

2.1

3.1 3.26.1

DC

5.0

1.0

3.0

4.0

2.0

6.0C

BA

D

Distance Vector

25

A

Dest Cost Next

1.0 0 --

2.0 0 --

3.0 1 C=2.2

D

Dest Cost Next

3.0 0 --

5.0 0 --

6.0 0 --

2.0 1 C=3.1

4.0 1 B=5.2

C

Dest Cost Next

2.0 0 --

3.0 0 --

1.0 1 A=2.1

5.0 1 D=3.2

6.0 1 D=3.2

B

Dest Cost Next

4.0 0 --

5.0 0 --

3.0 1 D=5.1

6.0 1 D=5.1

A

Dest Cost Next

1.0 0 --

2.0 0 --

3.0 1 C=2.2

5.0 2 C=2.2

6.0 2 C=2.2

D

Dest Cost Next

3.0 0 --

5.0 0 --

6.0 0 --

2.0 1 C=3.1

4.0 1 B=5.2

1.0 2 C=3.1

C

Dest Cost Next

2.0 0 --

3.0 0 --

1.0 1 A=2.1

5.0 1 D=3.2

6.0 1 D=3.2

4.0 2 D=3.2

B

Dest Cost Next

4.0 0 --

5.0 0 --

3.0 1 D=5.1

6.0 1 D=5.1

2.0 2 D=5.1

Distance Vector

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A

Dest Cost Next

1.0 0 --

2.0 0 --

3.0 1 C=2.2

5.0 2 C=2.2

6.0 2 C=2.2

4.0 3 C=2.2

D

Dest Cost Next

3.0 0 --

5.0 0 --

6.0 0 --

2.0 1 C=3.1

4.0 1 B=5.2

1.0 2 C=3.1

C

Dest Cost Next

2.0 0 --

3.0 0 --

1.0 1 A=2.1

5.0 1 D=3.2

6.0 1 D=3.2

4.0 2 D=3.2

B

Dest Cost Next

4.0 0 --

5.0 0 --

3.0 1 D=5.1

6.0 1 D=5.1

2.0 2 D=5.1

1.0 3 D=5.1

A

Dest Cost Next

1.0 0 --

2.0 0 --

3.0 1 C=2.2

5.0 2 C=2.2

6.0 2 C=2.2

D

Dest Cost Next

3.0 0 --

5.0 0 --

6.0 0 --

2.0 1 C=3.1

4.0 1 B=5.2

1.0 2 C=3.1

C

Dest Cost Next

2.0 0 --

3.0 0 --

1.0 1 A=2.1

5.0 1 D=3.2

6.0 1 D=3.2

4.0 2 D=3.2

B

Dest Cost Next

4.0 0 --

5.0 0 --

3.0 1 D=5.1

6.0 1 D=5.1

2.0 2 D=5.1

Distance Vector

Exchange updates directly

connected neighbors

periodically (on the order

of several seconds,

RIP:25-35 second)

other node is still

running

keep information

whenever table changes

(called triggered update)

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C

Dest Cost Next

2.0 0 --

3.0 0 --

1.0 1 A=2.1

5.0 1 D=3.2

6.0 1 D=3.2

4.0 2 D=3.2

5.12.2

4.1

5.2

1.1

2.1

3.1 3.2

6.1

DC

5.0

1.0

3.0

4.0

2.0

6.0C

BA

D

Update Example 1

F detects that link to G has failed

F sets distance to G to infinity and sends update t o A

A sets distance to G to infinity since it uses F to reach G

A receives periodic update from C with 2-hop path to G

A sets distance to G to 3 and sends update to F

F decides it can reach G in 4 hops via A

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D

G

A

F

E

B

C

Router

F

Dest Cost Next

x.0 1 G

F

Dest Cost Next

x.0 OO --

A

Dest Cost Next

x.0 OO --

A

Dest Cost Next

x.0 2 D

A

Dest Cost Next

x.0 00 C

C

Dest Cost Next

x.0 1 D

F

Dest Cost Next

x.0 3 A

x.0

Routing Loops Example 2

link from A to E fails

A advertises distance of infinity to E

B and C advertise a distance of 2 to E

B decides it can reach E in 3 hops; advertises this to A

A decides it can read E in 4 hops; advertises this to C

C decides that it can reach E in 5 hops…

29

A

Dest Cost Next

e.0 1 E

A

Dest Cost Next

e.0 OO --

B

Dest Cost Next

e.0 00 --

A

Dest Cost Next

e.0 4 B

B

Dest Cost Next

e.0 3 C

C

Dest Cost Next

e.0 2 A

C

Dest Cost Next

e.0 5 A

FAIL & UNSTABLE

B

Dest Cost Next

e.0 00 --

D

G

A

F

E

B

C

Router

e.0

Loop-Breaking Heuristics

Prevention:

Set infinity to 16 (to be problematic if the number of network enlarges and becomes more than 16 routers)

Split horizon (eg: B sends routing updates to A, B does not send tables (e.0, 2, A) to A because the routing is derived from A)

Split horizon with poison reverse (table (e.0, 2) remains sent by B to A with a certain sign that A does not use it).

Remains problematic: a long time convergency

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Routing Information Protocol (RIP)

Using the Principles of Distance Vector

Operates with UDP port 520

Destination is the Network, not router

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B

D

A

C

5.0

1.0

3.0

4.0

2.0

6.0

A

C

B

D

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RIPv1 Packet Format

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Command Version Unused (= zero)

Address Family

Identifier

Unused (= zero)

IP Address 1

Metric

Address Family

Identifier IP Address 2

Metric

0 8 16 31

Unused (= zero)

Unused (= zero)

Up to a maximum of 25

Unused (= zero)

Unused (= zero)

Unused (= zero)

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RIPv1 Packet Format

Command :Request value 1, response value 0

Version : value 1, RIP version 1

Address Family Identifier : value 2 for IP

IP Address : Address destination of the route.

Can be a mayor of the Network Address, subnet,

or host route

Metric : Cost, value between 1 and 16

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RIPv2 Packet Format

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Command Version Unused (= zero)

Address Family

Identifier

Route Tag

IP Address 1

Metric

Address Family

Identifier IP Address 2

Metric

0 8 16 31

Subnet Mask

Next Hop

Up to a maximum of 25

Subnet Mask

Next Hop

Route Tag

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RIPv2 Packet Format

Command: Request value 1, Response value 0 Version : value 2, RIP versi 2

Address Family Identifier : value 2 for IP

Route Tag : for tagging an external route, atau route that has been in the redistribution into the process of RIPv2

IP Address : Address destination of the route. Can be a mayor of Network Address, subnet, or route host

Subnet mask : mask 32 bit identifying network and subnet network IP

Next Hop : identify the best next hop address Metric : Cost, value between 1 and 16 35

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Configuring and

testing Router

CCNA Exploration

Topics

The Internetwork Operating System

(IOS).

Devices that have the IOS embedded.

IOS commands available to a device.

IOS modes of operation.

Basic IOS commands.

Basic show commands.

Configuration files 37

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Internetwork Operating

System

Most Cisco devices use the Cisco

IOS.

Details vary with the device and

feature set.

Normal access through a command

line.

Stored in flash memory and can be

upgraded.

Usually copied into RAM when the

device is powered on, and run from

RAM.

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Access to the interface

Console port via serial connection

Initial configuration

Disaster recovery

When network access has failed

Password recovery

As well as general management

Console access does not require a

password. Configure a password.

Lock the door.39

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Telnet, SSH, Aux

Later management can be via Telnet

There must be an IP address on the

port

A password must be configured

Secure shell gives better security

AUX port can be used locally or via

modem but by default does not show

error messages 40

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Configuration files

Hold the commands that have been

configured on the router to customise

it.

Running configuration in RAM holds

commands that are in current use

Startup configuration in NVRAM holds

saved commands. These are kept

when the power is off and usually

copied back into RAM when the router

is re-started.

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Router storage areas

ROM

Permanent

Holds POST, boot

instructions, basic IOS

Flash

Keeps contents

Holds IOS image

NVRAM

Keeps contents

Holds startup

configuration file

RAM

Volatile

Holds runnning config,

tables, queues etc

42 Computer Network - Industrial Engineering -

Faculty of Industrial Engineering

Router IOS modes

User EXEC mode

Privileged EXEC mode

enable disable+ password

Global Configuration mode

Configure terminal Exit or Ctrl+z

Specific Configuration modes

Exit EndVarious commands

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Router prompts

User EXEC mode

Privileged EXEC mode

Global Configuration mode

Specific Configuration modes

Router>

Router#

Router(config)#

Router(config-if)#

and others 44

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EXEC modes

You log in to User EXEC modeRouter>

You can give basic monitoring commands but cannot change the configuration

Enter enable to go to Privileged EXEC modeRouter#

Password may be used for security

You can give more commands and can go to configuration modes

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Configuration modes

Start in privileged EXEC mode and

enter the configure terminal (config

t) command

Router# config t

Router(config)#

The prompt changes

This is global configuration mode

Additional commands take you to

interface configuration, router

configuration etc.

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Leaving configuration modes

From interface configuration mode there are several ways of getting to privileged EXEC

Router(config-if)# exit Router(config)# exit Router#

Router(config-if)# endRouter#

Router(config-if)# Ctrl+zRouter#

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Command Structure

Followed by <Enter>48

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? To get help

? Gives a list of commands available

from the current prompt.

Command followed by space then ?

Gives a list of keywords or arguments

that can be used.

Start of command followed by ? with

no space shows how the word can be

continued.49

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Shortened commands

Router#show running-config

Router#show run

Router#sh ru

It needs enough letters of each word

to be unambiguous. (Tab key shows

whole word)

Router#s ru

% Ambiguous command: „s‟ 50

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Other error messages

Switch#clock set

% Incomplete command

Switch#clock set 19:50:00 25 6

% Invalid input detected at „^‟ marker

Router#show runming-config

% Invalid input detected at „^‟ marker

^

^51

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Keyboard shortcuts

Tab completes a partial command

Backspace erases to left of cursor

Ctrl+D erases at cursor (Delete does

not)

Ctrl+Z returns from any config mode

to privileged exec mode

Ctrl+C leave Setup mode

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At the ---More--- prompt

Enter shows the next line

Spacebar shows the next screenful

Needed with commands such as

show running-config that produce

more than one screen of text.

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Show commands

Show ? To get a list

Many different show commands to

give information about every aspect of

the router and its operation

We use some of the most common.

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General show commands

Show running-config shows the

configuration file from RAM

Show startup-config shows the

saved configuration file from NVRAM

Show version gives information

about the IOS and the router itself. It

shows the configuration register,

which controls how the router starts

up.55

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Show interfaces

Gives statistics for all interfaces

In particular, says if the interface is up

and if the protocol is up – important in

troubleshooting.

Show interfaces serial 0/0 to show

one selected interface

You can shorten to show int s 0/0

Show ip interfaces gives IP statistics56

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Save configuration

Router#copy running-config startup-

config

Router#copy run start (shortened)

Router#wr (Old fashioned, short for write,

but it works and is safe.)

Beware! A typing error in the copy

command can delete the operating system.

If you get an odd message about Flash –

hands off – call for help. 57

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Hostname

Router>enable

Router#config t

Router(config)#hostname Paris

Paris(config)#

Configure a suitable hostname so that

you know which router you are

managing and so that you can identify

it in network documentation. 58

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Console password

Paris(config)#line con 0

Paris(config-line)#password cisco

Paris(config-line)#login

Paris(config-line)#exit

Restricts access via the console

Use cisco as the password in labs.

Use a proper strong password on

production networks 59

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Vty password for Telnet

Paris(config)#line vty 0 4

Paris(config-line)#password cisco

Paris(config-line)#login

Paris(config-line)#exit

Allows and restricts access via 5 vty

lines

Use cisco as the password in labs.

Use a proper strong, different

password on production networks

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Enable and enable secret

Paris(config)#enable secret class

The password class is needed when

you type enable to enter privileged

exec mode

This password is encrypted

Paris(config)#enable password

cisco

Not encrypted, used on older routers

If you configure both, then only the

enable secret is used.

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Message of the day

Paris(config)#banner motd # No

unauthorised access #

# is a delimiter to show where the

message starts and ends.

Any character can be used as long as

it does not appear in the message.

The message should make it clear

that unauthorised access is forbidden.62

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Reload

Shuts down the router and then starts

it again.

If the configuration has changed then

you are prompted to save it.

The running configuration in RAM is

lost.

The startup configuration from

NVRAM is (usually) loaded into RAM

on startup.63

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Back up to TFTP server

Start TFTP server software on host

Paris#copy running-config tftp

Remote host []? 172.16.1.1

Name of configuration file to write

[Paris-config]? Paris12Oct07

Write file Paris12Oct07 to 172.16.1.1?

[confirm] y

Writing Paris12Oct07 ! ! ! ! ! ! [OK] 64

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Back up as text file

Start text capture

Name file

show run

Stop text capture

Open saved file and “tidy up”.

Remove unwanted symbols at –More-

--

No shutdown command on interfaces

Passwords in plain text (ouch!)

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TeraTerm text file

TeraTerm is an open source Telnet

client.

It can also act as a SSH client

It can capture text and save it as a

file.

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Erase startup configuration

Paris#erase NVRAM:startup-config

Paris#erase startup-config

Paris#erase start

If you reload, then the router starts up

with the default configuration. No

passwords, no IP addresses etc.

Caution if you get this command

wrong then you could erase

something else, e.g. IOS67

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Restore file from TFTP

server

Router#copy tftp running-config

You will be prompted for IP address

and file name.

Configuration is copied into RAM and

takes effect at once.

Save to NVRAM.

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Restore text file

Go to global configuration

mode

Hyperterminal Transfer

menu

Send text file…

Or

Copy text from text file

“Paste to host” into Hyperterminal session69

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Configure a router interface

Paris(config)#interface FastEthernet

0/0

Paris(config-if)#ip address 172.16.1.1

255.255.0.0

Paris(config-if)#no shutdown

Paris(config-if)#exit

Interface names vary, depending on

whether the router is modular and on

the bandwidth.

E.g. interface Ethernet 0 on an older

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Configure a router interface

Paris(config)#interface serial 0/0

Paris(config-if)#ip address

192.168.4.1 255.255.255.0

(Paris(config-if)#clock rate 64000)

Paris(config-if)#no shutdown

Paris(config-if)#exit

DCE only

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Description

Paris(config)#interface fa0/0

Paris(config-if)#description

Connects to Paris central switch

Can include circuit and contact

information

Not needed for the operation of the

router

Valuable for documentation as it is

included in the configuration listing72

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Switch interfaces

Switch physical interfaces do not have

IP addresses

They are active by default and do not

need the no shutdown command.

It can be useful to give them a

description.

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Switch IP address

The switch IP address goes on a

virtual interface, not a real one,

normally VLAN1.

SwA(config)#interface VLAN1

SwA(config-if)#ip address

172.16.255.1 255.255.0.0

SwA(config-if)#no shutdown

SwA(config-if)#exit 74

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Switch default gateway

SwA(config)#ip default gateway

172.16.255.254

Just like a workstation, a switch needs

a default gateway if it exchanges

messages with devices on a different

network.

The default gateway is the address of

the local router.75

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Interface – show commands

show interfaces states whether up or

down, gives some protocol

information and statistics about

interface use.

show ip interface gives IP addresses

and much more.

show ip interface brief gives

summary of IP addresses and

whether up/down. Very useful

command.

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Up or down

Interface status: Layer 1

Up

Down

Administratively down (no shutdown to

bring up)

Protocol: Layer 2

Up

Down (no keepalive signal received)77

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Ping – step by step

Ping 127.0.0.1 (loopback, is TCP/IP

OK?)

Ping own IP address (are NIC

hardware and software all right? Is IP

address bound?)

Ping local hosts (checks own

configuration and that of others)

Ping gateway

Ping other intermediate routers

Ping hosts on remote networks

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Network baseline

Measure and record performance

At different times

Under different conditions

Repeatedly over a period of time

Build up a record of network performance

Useful in troubleshooting and optimising the network

Helps predict future problems

Helps planning for change

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Find out about nodes

Ping – used from workstation, router

or switch – shows if destination can

be reached

Traceroute – shows hops along the

path

Arp -a on workstation – shows list of

MAC and IP addresses

show mac-address-table on switch –

shows list of MAC addresses and

switch ports

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The End