Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ITEC4610Network Switching and Routing

ดร . ประวิ�ทย์ ชุ�มชุ�หั�วิหัน้�าสาขาวิ�ชุาวิ�ศวิกรรมสารสน้เทศและการส��อสาร(ICE)MUTEmail: prawit@mut.ac.thหั�องท�างาน้: F402เบอรโทรศ�พทท#�ท�างาน้: (02)9883655 ต่%อ 220เบอรโทรศ�พทเคล��อน้ท#�: 065343850

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Class IVICMPv4, IPv6 และ ICMPv6

ดร . ประวิ�ทย์ ชุ�มชุ�หั�วิหัน้�าสาขาวิ�ชุาวิ�ศวิกรรมสารสน้เทศและการส��อสาร(ICE)MUTEmail: prawit@mut.ac.thหั�องท�างาน้: F402เบอรโทรศ�พทท#�ท�างาน้: (02)9883655 ต่%อ 220เบอรโทรศ�พทเคล��อน้ท#�: 065343850

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

หั�วิข�อท#�บรรย์าย์Introduction• ICMPv4• IPv6• ICMPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Introductionระด�บชุ�'น้ส��อสารท#� 3 ของ TCP/IP

IGMP = will talk in the class of multicasting

ICMPv4= This class

IPv4 = Last Class

ARP = Last Classes

IPv6 = This class

ICMPv6 = This class

IPv6IPv4

RARPARP

IGMP ICMP ICMPv6

Network layer in IPv4 Network layer in IPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

หั�วิข�อท#�บรรย์าย์• IntroductionICMPv4• IPv6• ICMPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Upon completion you will be able to:• Be familiar with the ICMP message format• Know the types of error reporting messages• Know the types of query messages• Be able to calculate the ICMP checksum• Know how to use the ping and traceroute commands• Understand the modules and interactions of an ICMP package

Objectives

Internet Control Message Internet Control Message ProtocolProtocol version 4version 4

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Position of ICMP in the network

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ICMP encapsulation

ICMP is network layer protocol but its messages are first encapsulated inside IP datagrams

Protocol Field in IP header =1

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ICMP messages are divided into error-reporting messages and query ICMP messages are divided into error-reporting messages and query messages. The error-reporting messages report problems that a router or messages. The error-reporting messages report problems that a router or a host (destination) may encounter. The query messages get specific a host (destination) may encounter. The query messages get specific information from a router or another host. information from a router or another host.

TYPES OF MESSAGES

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ICMP messagesICMP messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

An ICMP message has an 8-byte header and a variable-size data section. An ICMP message has an 8-byte header and a variable-size data section. Although the general format of the header is different for each Although the general format of the header is different for each message type, the first 4 bytes are common to all.message type, the first 4 bytes are common to all.

MESSAGE FORMAT

Type : defined in the previous slide

Code: the reason for particular message types

Checksum: calculated over the entire message (header and data).calculated over the entire message (header and data).

Rest of the header: specific for each message types

DATA: Error message information for finding the error packet

Query messages extra information

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

IP, as an unreliable protocol, is not concerned with error checking and IP, as an unreliable protocol, is not concerned with error checking and error control. ICMP was designed, in part, to compensate for this error control. ICMP was designed, in part, to compensate for this shortcoming. ICMP does not correct errors, it simply reports them.shortcoming. ICMP does not correct errors, it simply reports them.

The topics discussed in this section include:The topics discussed in this section include:

Destination UnreachableDestination UnreachableSource QuenchSource QuenchTime ExceededTime ExceededParameter ProblemParameter ProblemRedirectionRedirection

ERROR REPORTING

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ICMP always reports error messages to the original source.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Error-reporting messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

The following are important points about ICMP error messages:

❏ No ICMP error message will be generated in response to a datagram carrying an ICMP error message.❏ No ICMP error message will be generated for a fragmented datagram that is not the first fragment.❏ No ICMP error message will be generated for a datagram having a multicast address.❏ No ICMP error message will be generated for a datagram having a special address such as 127.0.0.0 or 0.0.0.0.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Contents of data field for the error messages

8 bytes :

Received datagram IP header:

Sent datagram IP header :

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Destination-unreachable format

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Error code• 0 : The network is unreachable• 1 : The host is unreachable• 2 : The protocol is unreachable• 3 : The port is unreachable• 4 : Fragmentation is required• 5 : Source routing could not be accomplished• 6 : The destination network is unknown• 7 : The destination host is unknown• 8 : The source is isolated• 9 : Communication with the destination network is administratively

prohibited• 10 : Communication with the destination host is administratively

prohibited• 11 : The network is unreachable for the specified type of service• 12 : The host is unreachable for the specified type of service• 13 : The host is unreachable because the administrator has put a filter on

it • 14 : The host is unreachable because the host precedence is violated• 15 : The host is unreachable because the host precedence was cut off

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Destination-unreachable messages with codes 2 or 3 can be created only

by the destination host.

Other destination-unreachable messages can be created only by

routers.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

A router cannot detect all problems that prevent the delivery of a packet.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

There is no flow-control mechanism in the IP protocol.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Source-quench format

Cause of Congestion

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

A source-quench message informs the source that a datagram has been

discarded due to congestion in a router or the destination host.

The source must slow down the sending of datagrams until the

congestion is relieved.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

One source-quench message is sent for each datagram that is discarded due to

congestion.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Whenever a router decrements a datagram with a time-to-live value to

zero, it discards the datagram and sends a time-exceeded message to the

original source.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

When the final destination does not receive all of the fragments in a set

time, it discards the received fragments and sends a time-exceeded message to

the original source.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

In a time-exceeded message, code 0 is used only by routers to show that the value of the time-to-live field is zero.

Code 1 is used only by the destination host to show that not all of the

fragments have arrived within a set time.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Time-exceeded message format

- TTL

- Timeout

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

A parameter-problem message can be created by a router or the destination

host.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Parameter-problem message format

0: Wrong header

1: Need options

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Redirection concept

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

A host usually starts with a small routing table that is gradually

augmented and updated. One of the tools to accomplish this is the

redirection message.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Redirection message format

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

A redirection message is sent from a router to a host on the same local

network.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ICMP can also diagnose some network problems through the query ICMP can also diagnose some network problems through the query messages, a group of four different pairs of messages. In this type of messages, a group of four different pairs of messages. In this type of ICMP message, a node sends a message that is answered in a specific ICMP message, a node sends a message that is answered in a specific format by the destination node. format by the destination node.

The topics discussed in this section include:The topics discussed in this section include:

Echo Request and ReplyEcho Request and ReplyTimestamp Request and ReplyTimestamp Request and ReplyAddress-Mask Request and ReplyAddress-Mask Request and ReplyRouter Solicitation and AdvertisementRouter Solicitation and Advertisement

QUERY

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Query messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

An echo-request message can be sent by a host or router. An echo-reply

message is sent by the host or router which receives an echo-request

message.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Echo-request and echo-reply messages can be used by network managers to

check the operation of the IP protocol.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Echo-request and echo-reply messages can test the reachability of a host. This

is usually done by invoking the ping command.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Echo-request and echo-reply messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Echo-request and echo-reply messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Timestamp-request and timestamp-reply messages can be used to

calculate the round-trip time between a source and a destination machine

even if their clocks are not synchronized.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

The timestamp-request and timestamp-reply messages can be used to synchronize two clocks in two

machines if the exact one-way time duration is known.

Note:Note:

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Mask-request and mask-reply message format

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Router-solicitation message format

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Router-advertisement message format

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

In ICMP the checksum is calculated over the entire message (header In ICMP the checksum is calculated over the entire message (header and data). and data).

The topics discussed in this section include:The topics discussed in this section include:

Checksum CalculationChecksum CalculationChecksum TestingChecksum Testing

CHECKSUM

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

The following Figure shows an example of checksum calculation for a simple echo-request message. We randomly chose the identifier to be 1 and the sequence number to be 9. The message is divided into 16-bit (2-byte) words. The words are added together and the sum is complemented. Now the sender can put this value in the checksum field.

See Next Slide

Example 1

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Example of checksum calculation

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

We introduce two tools that use ICMP for debugging: We introduce two tools that use ICMP for debugging: pingping and and traceroutetraceroute..

The topics discussed in this section include:The topics discussed in this section include:

PingPingTraceroute Traceroute

DEBUGGING TOOLS

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

We use the ping program to test the server fhda.edu. The result is shown below:

See Next Slide

$ ping fhda.eduPING fhda.edu (153.18.8.1) 56 (84) bytes of data.64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=0 ttl=62 time=1.91 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=1 ttl=62 time=2.04 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=2 ttl=62 time=1.90 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=3 ttl=62 time=1.97 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=4 ttl=62 time=1.93 ms

Example 2

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=5 ttl=62 time=2.00 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=6 ttl=62 time=1.94 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=7 ttl=62 time=1.94 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=8 ttl=62 time=1.97 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=9 ttl=62 time=1.89 ms64 bytes from tiptoe.fhda.edu (153.18.8.1): icmp_seq=10 ttl=62 time=1.98 ms

--- fhda.edu ping statistics ---11 packets transmitted, 11 received, 0% packet loss, time 10103ms

rtt min/avg/max = 1.899/1.955/2.041 ms

Example 2 (Continued)

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

For the this example, we want to know if the adelphia.net mail server is alive and running. The result is shown below:$ ping mail.adelphia.netPING mail.adelphia.net (68.168.78.100) 56(84) bytes of data.64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=0 ttl=48 time=85.4 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=1 ttl=48 time=84.6 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=2 ttl=48 time=84.9 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=3 ttl=48 time=84.3 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=4 ttl=48 time=84.5 ms

See Next Slide

Example 3

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=5 ttl=48 time=84.7 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=6 ttl=48 time=84.6 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=7 ttl=48 time=84.7 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=8 ttl=48 time=84.4 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=9 ttl=48 time=84.2 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=10 ttl=48 time=84.9 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=11 ttl=48 time=84.6 ms64 bytes from mail.adelphia.net (68.168.78.100): icmp_seq=12 ttl=48 time=84.5 ms

--- mail.adelphia.net ping statistics ---

14 packets transmitted, 13 received, 7% packet loss, time 13129msrtt min/avg/max/mdev = 84.207/84.694/85.469

Example 3

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Example 3

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

We use the traceroute program to find the route from the computer voyager.deanza.edu to the server fhda.edu. The following shows the result:

See Next Slide

$ traceroute fhda.edutraceroute to fhda.edu (153.18.8.1), 30 hops max, 38 byte packets1 Dcore.fhda.edu (153.18.31.254) 0.995 ms 0.899 ms 0.878 ms2 Dbackup.fhda.edu (153.18.251.4) 1.039 ms 1.064 ms 1.083 ms3 tiptoe.fhda.edu (153.18.8.1) 1.797 ms 1.642 ms 1.757 ms

Example 4

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

The un-numbered line after the command shows that the destination is 153.18.8.1. The TTL value is 30 hops. The packet contains 38 bytes: 20 bytes of IP header, 8 bytes of UDP header, and 10 bytes of application data. The application data is used by traceroute to keep track of the packets.

The first line shows the first router visited. The router is named Dcore.fhda.edu with IP address 153.18.31.254. The first round trip time was 0.995 milliseconds, the second was 0.899 milliseconds, and the third was 0.878 milliseconds.

The second line shows the second router visited. The router is named Dbackup.fhda.edu with IP address 153.18.251.4. The three round trip times are also shown. The third line shows the destination host. We know

that this is the destination host because there are no more lines. The destination host is the server fhda.edu, but it is named tiptoe. fhda.edu with the IP address 153.18.8.1. The three round trip times are also shown.

Example 4 (Continued)

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

In this example, we trace a longer route, the route to xerox.com$ traceroute xerox.comtraceroute to xerox.com (13.1.64.93), 30 hops max, 38 byte packets1 Dcore.fhda.edu (153.18.31.254) 0.622 ms 0.891 ms 0.875 ms2 Ddmz.fhda.edu (153.18.251.40) 2.132 ms 2.266 ms 2.094 ms...

18 alpha.Xerox.COM (13.1.64.93) 11.172 ms 11.048 ms 10.922 ms

Here there are 17 hops between source and destination. Note that some round trip times look unusual. It could be that a router is too busy to process the packet immediately.

Example 5

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

An interesting point is that a host can send a traceroute packet to itself. This can be done by specifying the host as the destination. The packet goes to the loopback address as we expect.$ traceroute voyager.deanza.edutraceroute to voyager.deanza.edu (127.0.0.1), 30 hops max, 38 byte packets1 voyager (127.0.0.1) 0.178 ms 0.086 ms 0.055 ms

Example 6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Finally, we use the traceroute program to find the route between fhda.edu and mhhe.com (McGraw-Hill server). We notice that we cannot find the whole route. When traceroute does not receive a response within 5 seconds, it prints an asterisk to signify a problem, and then tries the next hop..

$ traceroute mhhe.comtraceroute to mhhe.com (198.45.24.104), 30 hops max, 38 byte packets1 Dcore.fhda.edu (153.18.31.254) 1.025 ms 0.892 ms 0.880 ms2 Ddmz.fhda.edu (153.18.251.40) 2.141 ms 2.159 ms 2.103 ms3 Cinic.fhda.edu (153.18.253.126) 2.159 ms 2.050 ms 1.992 ms ...16 * * *17 * * *...............

Example 7

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

To give an idea of how ICMP can handle the sending and receiving of To give an idea of how ICMP can handle the sending and receiving of ICMP messages, we present our version of an ICMP package made of ICMP messages, we present our version of an ICMP package made of two modules: an input module and an output module. two modules: an input module and an output module.

The topics discussed in this section include:The topics discussed in this section include:

Input ModuleInput ModuleOutput ModuleOutput Module

ICMP PACKAGE

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ICMP package

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ค�าถาม?

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ดท�าย์บทลองท�าด�

1 2 3

AIPA=1

D

CIPA=8

L5L4L3L2L1 L1

L3L2L1

L2L1

L3L2L1

L2L1

L3L2L1

L2L1

L5L4L3L2L1L1

1010101011….. 101011….. 101011….. 101010….. 1010101010001011…..

B

IPA1=2, IPA2=3 IPA1=4, IPA2=5 IPA1=6, IPA2=7

SA=Source IP AddressDA=Destination IP AddressIPA=IP Address

IPA1=X,IPA2=Z IPA1=W,IPA2=Y

H 1 8 DATA

H SA DA DATA

ABC

D EFG

ถ้�าแพ็�คเก็�ตหายที่��จุ�ดต�าง ๆ ด�งรู�ป ICMP ตอบสนองอย�างไรูบ�างA, B, C, D, E, F,G

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ดท�าย์บทลองท�าด�• Exercise 13: How can we determine if

an IP packet is carrying an ICMP packet?

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ดท�าย์บทลองท�าด�• Exercise 17: An ICMP message has

arrived with the header (in hexadecimal): 03 03 10 20 00 00 00 00 00– What is the type of the message?– What is the code ?– What is purpose of the message ?

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ดท�าย์บทลองท�าด�• ถ�าค�ณต่�องการทราบวิ%าคอมพ�วิเต่อร IPv4

เคร��องหัน้,�งม#การเป-ดใหั�บร�การโปรแกรมประย์�กต่อะไรบ�างน้�กศ,กษาสามารถท�าได�อย์%าง ถ�าน้�กศ,กษาม#คอมพ�วิเต่อรท#�ม#การเชุ��อมต่%อเคร�อข%าย์ IPv4 ก�บคอมพ�วิเต่อรเคร��องน้�'น้

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

หั�วิข�อท#�บรรย์าย์• Introduction• ICMPv4IPv6• ICMPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Upon completion you will be able to:

• Understand the shortcomings of IPv4 • Know the IPv6 address format, address types, and abbreviations• Be familiar with the IPv6 header format• Know the extension header types• Know the differences between ICMPv4 and ICMPv6• Know the strategies for transitioning from IPv4 to IPv6

Objectives

Next Generation: IPv6 Next Generation: IPv6 and ICMPv6and ICMPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

IPv6 has these advantages over IPv4: IPv6 has these advantages over IPv4: 1. 1. larger address space larger address space 128 bits 32 bits 128 bits 32 bits2. 2. better header format better header format keep header overhead to a minimum keep header overhead to a minimum 3. 3. new options new options additional functionalities additional functionalities4. 4. allowance for extension allowance for extension for new technologies or applications for new technologies or applications5. 5. support for resource allocation support for resource allocation using flow label for QoS using flow label for QoS 6. 6. support for more security support for more security confidentially and integrity of the packets confidentially and integrity of the packets

The topics discussed in this section include:The topics discussed in this section include:

IPv6 Addresses IPv6 Addresses Address Space Assignment Address Space Assignment Packet Format Packet Format Comparison between IPv4 and IPv6 Comparison between IPv4 and IPv6

IPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

IPv6 address

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Abbreviated address

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Abbreviated address with consecutive zeros

ย�อได�ครู� งเด�ยวเที่�าน� นต�อ 1หมายเลข IP

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

CIDR address

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Address structure

See next slide for types of prefix

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Type prefixes for IPv6 Type prefixes for IPv6 addressesaddresses

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Provider-based address

Type identifier 010:a provider-based address

Registry 11000:North America

01000:European

10100:Asian and Pacific countries

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Address hierarchy

Provider prefix an ISP, variable-length

Subscriber prefix an organization subscriber, 24 bits

Subnet prefix a network under a territory of the subscriber, 32 bits

Node Identifier the identity of node connected to the subnet 48 bits

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Unspecified address

For:

- a host does no know its own address

- A host sends an inquiry to find its address

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Loopback Address

For:

-used by a host to test itself without going on the networks

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Compatible address

-Used when a computer using IPv6 wants to send a packet to another computer using IPv6

- the packet passes through IPv4 networks

IPv6 IPv4 IPv6

0x02 2

0x0D13

0x1117

0x0E14

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Mapped address

For:

-Used when a computer that has migrated to IPv6 want to sent a packet to a computer still using IPv4

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Link local address

For:

- Used in an isolated network

- Does not have a global effect

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Site local address

For:

-Used for a site with several networks- Used in isolated networks- Does not have a global effect

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Multicast address

For:

- For a group of hosts

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

IPv6 datagram

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Format of an IPv6 datagram

Flow label: a particular flow of data

Payload length: length of IP datagram excluding the base header(40 bytes)

Next Header: Header following the base header

Hop limit: TTL

Source Address: the original source IP address

Destination Address: the final destination IP address

Version: version 6Priority: packet priorities

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Next header codesNext header codes

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Priorities for congestion-Priorities for congestion-controlled controlled

traffic traffic

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Priorities for Priorities for noncongestion-controllednoncongestion-controlled

traffic traffic

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Comparison between IPv4 Comparison between IPv4 and IPv6 packet headerand IPv6 packet header

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Extension header format

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Extension header types

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Hop-by-hop option header format

Used when the source needs to pass information to all router visited by the datagram

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

The format of options in a hop-by-hop option header

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Pad1

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

PadN

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Jumbo payload

For:

- normally the IP datagram can be a maximum of 65535 bytes

- Jumbo payload =2^32-1 (4,294,967,295 bytes)

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Source routing

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Source routing example

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Fragmentation

- Only the source could do

- PATH MTU Discovery technique

-If no path MTU discovery, a size of 576 bytes of smaller

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Authentication

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Calculation of authentication data

The authentication header validates the message sender and ensures the integrity of data

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Encrypted security payload

Providing confidentiality (รู�ก็ษาความล�บ) and guards against eavesdropping (ด�งฟั'ง)

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Transport mode encryption

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Tunnel-mode encryption

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Comparison between IPv4 Comparison between IPv4 options and IPv6 options and IPv6 extensionextension headersheaders

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ค�าถาม?

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ดลองท�าด�• Exercise 2: Show the original

(unabbreviated) form of the following address:

a. 0::0b. 0:AA::0c. 0:1234::3d. 123::1:2

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ดลองท�าด�• Exercise 3: What is the type of the

following addresses:a. FE80::12b. FEC0::24A2c. FE02::0d. 0::01

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ดลองท�าด�• Exercise 14: A host has the address

581E:1456:2314:ABCD::1211. If the node identification is 48 bits and the subnet identification is 32 bits, find the provider prefix?

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ด• Exercise 28: what is the ip-

compatible address for 119.254.254.254?

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ด• Exercise 29: what is the ip-mapped

address for 119.254.254.254?

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

หั�วิข�อท#�บรรย์าย์• Introduction• ICMPv4• IPv6ICMPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ICMPv6, while similar in strategy to ICMPv4, has changes that makes it ICMPv6, while similar in strategy to ICMPv4, has changes that makes it more suitable for IPv6. ICMPv6 has absorbed some protocols that were more suitable for IPv6. ICMPv6 has absorbed some protocols that were independent in version 4.independent in version 4.

The topics discussed in this section include:The topics discussed in this section include:

Error Reporting Error Reporting Query Query

ICMPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Comparison of network layers in

version 4 and version 6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Categories of ICMPv6 messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

General format of ICMP messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Error-reporting messages

Destination Unreachable: The same concept as in ICMPv4

Packet too big: a router receives a packet that is larger than MTU

Time exceed: Have not arrived within the time limit

Parameter problems: Error in header fields, an unrecognized extension header, an unrecognized option

Redirection: the same concept as in ICMPv4

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Comparison of error-Comparison of error-reporting messages in reporting messages in

ICMPv4 and ICMPv6ICMPv4 and ICMPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Destination-unreachable message format

0: No path to destination

1: Communication is prohibited

2: Strict source routing is impossible.

3: Destination address is unreachable.

4: Port is not available.

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Packet-too-big message format

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Time-exceeded message format

0: a hop limit field =0

1: not arrived within the time limit for fragments of datagram

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Parameter-problem message format

0: Error in header fields

1:an unrecognized extension header

2: an unrecognized option

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Redirection message format

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Query messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Comparison of query Comparison of query messages in messages in

ICMPv4 and ICMPv6ICMPv4 and ICMPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Echo request and reply messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Router-solicitation and advertisement message formats

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Neighbor-solicitation and advertisement message

formats

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Group-membership messages

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Group-membership message formats

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Four situations of group-membership operation

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Three strategies have been devised by the IETF to provide for a smooth Three strategies have been devised by the IETF to provide for a smooth transition from IPv4 to IPv6.transition from IPv4 to IPv6.

The topics discussed in this section include:The topics discussed in this section include:

Dual Stack Dual Stack Tunneling Tunneling Header Translation Header Translation

TRANSITION FROM IPv4 TO IPv6

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Three transition strategies

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Dual stack

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Automatic tunneling

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Configured tunneling

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Header translation

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Header translationHeader translation

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

Summary

• ICMPv4 • IPv6• ICMP6• Next Class RIPv1 และ RIPv2

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

ค�าถาม?

Info

rmatio

n a

nd

C

om

munica

tion e

ng

ineerin

g

(ICE)

MUT

แบบฝึ*กหั�ดลองท�าด�• Exercise 18: what type of ICMP

messages contain of the IP datagram? Why is this included?