Chapter 6 IPv4 Addresses Part 3

1
Chapter 6IPv4 Addresses Part 3

• CSIS 76 Networking Essentials
• Randy Arvay
• Monterey Peninsula College
• rarvay_at_mpc.edu

2
Topics

• Calculating the number subnets/hosts needed
• VLSM (Variable Length Subnet Masks)
• Classful Subnetting
• IPv6
• ICMP Ping and Traceroute

3
Calculating the number subnets/hosts needed
4
Calculating the number subnets/hosts needed
172.16.1.0
255.255.255.0
Network
Host

• Network 172.16.1.0/24
• Need
• As many subnets as possible, 60 hosts per subnet

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Calculating the number subnets/hosts needed
Number of hosts per subnet
172.16.1. 0 0 0 0 0 0 0 0
255.255.255. 0 0 0 0 0 0 0 0
6 host bits
Network
Host

• Network 172.16.1.0/24
• Need
• As many subnets as possible, 60 hosts per subnet

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Calculating the number subnets/hosts needed
Number of subnets
172.16.1. 0 0 0 0 0 0 0 0
255.255.255. 1 1 0 0 0 0 0 0
255.255.255.192
6 host bits
Network
Host

• Network 172.16.1.0/24
• Need
• As many subnets as possible, 60 hosts per subnet
• New Subnet Mask 255.255.255.192 (/26)
• Number of Hosts per subnet 6 bits, 64-2 hosts,
  62 hosts
• Number of Subnets 2 bits or 4 subnets

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Calculating the number subnets/hosts needed
172.16.1.0
255.255.255.0
Network
Host

• Network 172.16.1.0/24
• Need
• As many subnets as possible, 12 hosts per subnet

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Calculating the number subnets/hosts needed
Number of hosts per subnet
172.16.1. 0 0 0 0 0 0 0 0
255.255.255. 0 0 0 0 0 0 0 0
4 host bits
Network
Host

• Network 172.16.1.0/24
• Need
• As many subnets as possible, 12 hosts per subnet

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Calculating the number subnets/hosts needed
Number of hosts per subnet
Number of subnets
172.16.1. 0 0 0 0 0 0 0 0
255.255.255. 1 1 1 1 0 0 0 0
255.255.255.240
4 host bits
Network
Host

• Network 172.16.1.0/24
• Need
• As many subnets as possible, 12 hosts per subnet
• New Subnet Mask 255.255.255.240 (/28)
• Number of Hosts per subnet 4 bits, 16-2 hosts,
  14 hosts
• Number of Subnets 4 bits or 16 subnets

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Calculating the number subnets/hosts needed
172.16.1.0
255.255.255.0
Network
Host

• Network 172.16.1.0/24
• Need
• Need 6 subnets, as many hosts per subnet as
  possible

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Calculating the number subnets/hosts needed
Number of subnets
172.16.1. 0 0 0 0 0 0 0 0
255.255.255. 0 0 0 0 0 0 0 0
3 subnet bits
Network
Host

• Network 172.16.1.0/24
• Need
• Need 6 subnets, as many hosts per subnet as
  possible

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Calculating the number subnets/hosts needed
Number of hosts per subnet
Number of subnets
172.16.1. 0 0 0 0 0 0 0 0
255.255.255. 1 1 1 0 0 0 0 0
255.255.255.224
3 subnet bits
Network
Host

• Network 172.16.1.0/24
• Need
• Need 6 subnets, as many hosts per subnet as
  possible
• New Subnet Mask 255.255.255.224 (/27)
• Number of Hosts per subnet 5 bits, 32-2 hosts,
  30 hosts
• Number of Subnets 3 bits or 8 subnets

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VLSM (Variable Length Subnet Masks)
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VLSM

• If you know how to subnet, you can do VLSM.
• Example 10.0.0.0/8
• Subnet in /16 subnets
• 10.0.0.0/16
• 10.1.0.0/16
• 10.2.0.0/16
• 10.3.0.0/16
• Etc.
• Subnet one of the subnets (10.1.0.0/16)
• 10.1.0.0/24
• 10.1.1.0/24
• 10.1.2.0/24
• 10.1.3.0/24
• etc

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VLSM
Host can only be a member of the subnet. Host can
NOT be a member of the network that was subnetted.
YES!
10.2.1.55/24
10.2.1.55/16
NO!
All other /16 subnets are still available for use
as /16 networks or to be subnetted.
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VLSM Using the chart

• This chart can be used to help determine subnet
  addresses.
• This can any octet.
• Well keep it simple and make it the fourth
  octet.
• Network 172.16.1.0/24
• What if we needed 4 subnets?
• What would the Mask be?
• What would the addresses of each subnet be?
• What would the range of hosts be for each subnet?

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VLSM Using the chart

• Network 172.16.1.0/24
• What if we needed 4 subnets?
• What would the Mask be?
• 255.255.255.192 (/26)
• What would the addresses of each subnet be?
• 172.16.1.0/26
• 172.16.1.64/26
• 172.16.1.128/26
• 172.16.1.192/26
• What would the range of hosts be for each subnet?
• 172.16.1.0/26 172.16.1.1-172.16.1.62
• 172.16.1.64/26 172.16.1.65-172.16.1.126
• 172.16.1.128/26 172.16.1.129-172.16.1.191
• 172.16.1.192/26 172.16.1.193-172.16.1.254

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VLSM Using the chart
16 /30 subnets

• What if we needed several (four) /30 subnets for
  our serial links?
• Take one of the /26 subnets and subnet it again
  into /30 subnets.

Still have 3 /26 subnets
16 /30 subnets
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Classful Subnetting
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Classful IP Addressing

• In the early days of the Internet, IP addresses
  were allocated to organizations based on request
  rather than actual need.
• When an organization received an IP network
  address, that address was associated with a
  Class, A, B, or C.
• This is known as Classful IP Addressing
• The first octet of the address determined what
  class the network belonged to and which bits were
  the network bits and which bits were the host
  bits.
• There were no subnet masks.
• It was not until 1992 when the IETF introduced
  CIDR (Classless Interdomain Routing), making the
  address class meaning less.
• This is known as Classless IP Addressing.
• For now, all you need to know is that todays
  networks are classless, except for some things
  like the structure of Ciscos IP routing table
  and for those networks that still use Classful
  routing protocols.
• You will learn more about this is CIS 82, CIS 83
  and CIS 185.

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IPv4 Address Classes
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Address Classes
1st octet
2nd octet
3rd octet
4th octet
Class A
Network
Host
Host
Host
Class B
Network
Network
Host
Host
Class C
Network
Network
Network
Host
N Network number assigned by ARIN (American
Registry for Internet Numbers) H Host number
assigned by administrator
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Class A addresses
Default Mask 255.0.0.0 (/8)
First octet is between 0 127, begins with 0
With 24 bits available for hosts, there a 224
possible addresses. Thats 16,777,216 nodes!
Number between 0 - 127

• There are 126 class A addresses.
• 0 and 127 have special meaning and are not used.
• 16,777,214 host addresses, one for network
  address and one for broadcast address.
• Only large organizations such as the military,
  government agencies, universities, and large
  corporations have class A addresses.
• For example ISPs have 24.0.0.0 and 63.0.0.0
• Class A addresses account for 2,147,483,648 of
  the possible IPv4 addresses.
• Thats 50 of the total unicast address space,
  if classful was still used in the Internet!

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Class B addresses
Default Mask 255.255.0.0 (/16)
First octet is between 128 191, begins with 10
Network
Network
Host
Host
With 16 bits available for hosts, there a 216
possible addresses. Thats 65,536 nodes!
Number between 128 - 191

• There are 16,384 (214) class B networks.
• 65,534 host addresses, one for network address
  and one for broadcast address.
• Class B addresses represent 25 of the total IPv4
  unicast address space.
• Class B addresses are assigned to large
  organizations including corporations (such as
  Cisco, government agencies, and school districts).

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Class C addresses
Default Mask 255.255.255.0 (/24)
First octet is between 192 223, begins with 110
Network
Network
Network
Host
With 8 bits available for hosts, there a 28
possible addresses. Thats 256 nodes!
Number between 192 - 223

• There are 2,097,152 possible class C networks.
• 254 host addresses, one for network address and
  one for broadcast address.
• Class C addresses represent 12.5 of the total
  IPv4 unicast address space.

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IPv4 Address Classes

• No medium size host networks
• In the early days of the Internet, IP addresses
  were allocated to organizations based on request
  rather than actual need.

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Network based on first octet

• The network portion of the IP address was
  dependent upon the first octet.
• There was no Base Network Mask provided by the
  ISP.
• The network mask was inherent in the address
  itself.

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IPv4 Address Classes

• Class D Addresses
• A Class D address begins with binary 1110 in the
  first octet.
• First octet range 224 to 239.
• Class D address can be used to represent a group
  of hosts called a host group, or multicast group.
• Class E AddressesFirst octet of an IP address
  begins with 1111
• Class E addresses are reserved for experimental
  purposes and should not be used for addressing
  hosts or multicast groups. 

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Fill in the information

• 1. 192.168.1.3 Class _____ Default
  Mask______________
• Network _________________ Broadcast
  ________________
• Hosts _________________ through
  ___________________
• 2. 1.12.100.31 Class ______ Default
  Mask______________
• Network _________________ Broadcast
  ________________
• Hosts _________________ through
  _____________________
• 3. 172.30.77.5 Class ______ Default
  Mask______________
• Network _________________ Broadcast
  ________________
• Hosts _________________ through
  _____________________

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Fill in the information

• 1. 192.168.1.3 Class C Default Mask
  255.255.255.0
• Network 192.168.1.0 Broadcast 192.168.1.255
• Hosts 192.168.1.1 through
  192.168.1.254
• 2. 1.12.100.31 Class A Default Mask
  255.0.0.0
• Network 1.0.0.0 Broadcast 1.255.255.255
• Hosts 1.0.0.1 through 1.255.255.254
• 3. 172.30.77.5 Class B Default Mask
  255.255.0.0
• Network 172.30.0.0 Broadcast 172.30.255.255
• Hosts 172.30.0.1. through 172.30.255.254

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Class separates network from host bits

• The Class determines the Base Network Mask!
• 1. 192.168.1.3 Class C Default Mask
  255.255.255.0
• Network 192.168.1.0
• 2. 1.12.100.31 Class A Default Mask
  255.0.0.0
• Network 1.0.0.0
• 3. 172.30.77.5 Class B Default Mask
  255.255.0.0
• Network 172.30.0.0

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Know the classes!

• First First Network Host
• Class Bits Octet Bits Bits
• A 0 0 127 8 24
• B 10 128 - 191 16 16
• C 110 192 - 223 24 8
• D 1110 224 239
• E 1111 240 - 255

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IP addressing crisis

• Address Depletion
• Internet Routing Table Explosion

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IPv4 Addressing

• Subnet Mask
• One solution to the IP address shortage was
  thought to be the subnet mask.
• Formalized in 1985 (RFC 950), the subnet mask
  breaks a single class A, B or C network in to
  smaller pieces.
• This does allow a network administrator to divide
  their network into subnets.
• Routers still associated an network address with
  the first octet of the IP address.

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All Zeros and All Ones Subnets

• Using the All Ones Subnet
• There is no command to enable or disable the use
  of the all-ones subnet, it is enabled by default.
• Router(config)ip subnet-zero
• The use of the all-ones subnet has always been
  explicitly allowed and the use of subnet zero is
  explicitly allowed since Cisco IOS version 12.0.
• RFC 1878 states, "This practice (of excluding
  all-zeros and all-ones subnets) is obsolete!
  Modern software will be able to utilize all
  definable networks." Today, the use of subnet
  zero and the all-ones subnet is generally
  accepted and most vendors support their use,
  though, on certain networks, particularly the
  ones using legacy software, the use of subnet
  zero and the all-ones subnet can lead to
  problems.
• CCO Subnet Zero and the All-Ones Subnet
  http//www.cisco.com/en/US/tech/tk648/tk361/techno
  logies_tech_note09186a0080093f18.shtml

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Long Term Solution IPv6 (coming)

• IPv6, or IPng (IP the Next Generation) uses a
  128-bit address space, yielding
• 340,282,366,920,938,463,463,374,607,431,768,2
  11,456
• possible addresses.
• IPv6 has been slow to arrive
• IPv6 requires new software IT staffs must be
  retrained
• IPv6 will most likely coexist with IPv4 for years
  to come.
• Some experts believe IPv4 will remain for more
  than 10 years.

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Short Term Solutions IPv4 Enhancements

• Discussed in CSIS 177 and CSIS 179
• CIDR (Classless Inter-Domain Routing) RFCs
  1517, 1518, 1519, 1520
• VLSM (Variable Length Subnet Mask) RFC 1009
• Private Addressing - RFC 1918
• NAT/PAT (Network Address Translation / Port
  Address Translation) RFC
• More later when we discuss TCP

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• 11111111.00000000.00000000.00000000 /8
  (255.0.0.0) 16,777,216 host addresses
• 11111111.10000000.00000000.00000000 /9
  (255.128.0.0) 8,388,608 host addresses
• 11111111.11000000.00000000.00000000 /10
  (255.192.0.0) 4,194,304 host addresses
• 11111111.11100000.00000000.00000000 /11
  (255.224.0.0) 2,097,152 host addresses
• 11111111.11110000.00000000.00000000 /12
  (255.240.0.0) 1,048,576 host addresses
• 11111111.11111000.00000000.00000000 /13
  (255.248.0.0) 524,288 host addresses
• 11111111.11111100.00000000.00000000 /14
  (255.252.0.0) 262,144 host addresses
• 11111111.11111110.00000000.00000000 /15
  (255.254.0.0) 131,072 host addresses
• 11111111.11111111.00000000.00000000 /16
  (255.255.0.0) 65,536 host addresses
• 11111111.11111111.10000000.00000000 /17
  (255.255.128.0) 32,768 host addresses
• 11111111.11111111.11000000.00000000 /18
  (255.255.192.0) 16,384 host addresses
• 11111111.11111111.11100000.00000000 /19
  (255.255.224.0) 8,192 host addresses
• 11111111.11111111.11110000.00000000 /20
  (255.255.240.0) 4,096 host addresses
• 11111111.11111111.11111000.00000000 /21
  (255.255.248.0) 2,048 host addresses
• 11111111.11111111.11111100.00000000 /22
  (255.255.252.0) 1,024 host addresses
• 11111111.11111111.11111110.00000000 /23
  (255.255.254.0) 512 host addresses
• 11111111.11111111.11111111.00000000 /24
  (255.255.255.0) 256 host addresses
• 11111111.11111111.11111111.10000000 /25
  (255.255.255.128) 128 host addresses
• 11111111.11111111.11111111.11000000 /26
  (255.255.255.192) 64 host addresses

ISPs no longer restricted to three classes. Can
now allocate a large range of network addresses
based on customer requirements
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Active BGP entries March, 2006

• http//bgp.potaroo.net/

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ISP/NAP Hierarchy - The Internet Still
hierarchical after all these years. Jeff Doyle
(Tries to be anyways!)
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IPv6
42
Background

• That short-term solution was Network Address
  Translation (NAT) and RFC 1918.
• There are two fundamental drivers behind the
  growing recognition of the need for IPv6. (NAT
  stifles innovation in these areas.)
• New applications using core concepts such as
• mobile IP
• service quality guarantees
• end-to-end security
• peer-to-peer networking.
• Rapid modernization of heavily populated
  countries such as India and China.
• A compelling statistic is that the number of
  remaining unallocated IPv4 addresses is almost
  the same as the population of China about 1.3
  billion.

43
IPv6

• IPv6 replaces the 32-bit IPv4 address with a
  128-bit address, making 340 trillion trillion
  trillion IP addresses available.
• 340,282,366,920,938,463,463,374,607,431,768,211,45
  6 addresses
• Represented by breaking them up into eight 16-bit
  segments.
• Each segment is written in hexadecimal between
  0x0000 and 0xFFFF, separated by colons.
• An example of a written IPv6 address is
•     3ffe19440100000a000000bc25000d0b

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Global Unicast Addresses
Replaced with

• Note This format, specified in RFC 3587,
  obsoletes and simplifies an earlier format that
  divided the IPv6 unicast address into Top Level
  Aggregator (TLA), Next-Level Aggregator (NLA),
  and other fields. However, you should be aware
  that this obsolescence is relatively recent and
  you are likely to encounter some books and
  documents that show the old IPv6 address format.

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Global Unicast Addresses

• The host portion of the address is called the
  Interface ID.
• The reason for this name is that a host can have
  more than one IPv6 interface, and so the address
  more correctly identifies an interface on a host
  than a host itself.
• But that subtlety only goes so far
• A single interface can have
• multiple IPv6 addresses, and
• an IPv4 address in addition.

46
Global Unicast Addresses

• Subnet Identifier is part of the network portion
  of the address rather than the host portion.
• A big benefit is that the Interface ID can be a
  consistent size for all IPv6 addresses.
• And making the Subnet ID a part of the network
  portion creates a clear separation of functions
• The network portion provides the location of a
  device down to the specific data link
• and
• the host portion provides the identity of the
  device on the data link.

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Global Unicast Addresses

• With very few exceptions
• Interface ID is 64 bits
• Subnet ID field is 16 bits
• provides for 65,536 separate subnets
• The IANA and the Regional Internet Registries
  (RIRs) assign IPv6 prefixesnormally /32 or /35
  in lengthto the Local Internet Registries
  (LIRs).
• The LIRs, which are usually large Internet
  Service Providers, then allocate longer prefixes
  to their customers. In the majority of cases, the
  prefixes assigned by the LIRs are /48.

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Background

• IPv4 will exist for some time, as the transition
  begins to IPv6.
• Other new protocols have been developed in
  support of IPv6
• Routing protocols (OSPFv3) so routers can learn
  about IPv6 network addresses.
• ICMPv6

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(No Transcript)
50
ICMP Ping and Trace
51
Partial list

• ICMP (Internet Control Message Protocol)
• ICMP A Layer 3 protocol
• Used for sending messages
• Encapsulated in a Layer 3, IP packet
• Uses Type and Code fields for various messages

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ICMP

• Unreachable Destination or Service
• Used to notify a host that the destination or
  service is unreachable.
• When a host or router receives a packet that it
  cannot deliver, it may send an ICMP Destination
  Unreachable packet to the host originating the
  packet.
• The Destination Unreachable packet will contain
  codes that indicate why the packet could not be
  delivered.
• From a router
• 0 network unreachable Does not have a route
  in the routing table
• 1 host unreachable Has a route but cant find
  host. (end router)
• From a host
• 2 protocol unreachable
• 3 port unreachable
• Service is not available because no daemon is
  running providing the service or because security
  on the host is not allowing access to the service.

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172.30.1.20
172.30.1.25
54

• Ping
• Uses ICMP message encapsulated within an IP
  Packet
• Protocol field 1
• Does not use TCP or UDP
• Format
• ping ip address (or ping ltcrgt for extended ping)
• ping 172.30.1.25

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• Echo Request
• The sender of the ping, transmits an ICMP
  message, Echo Request
• Echo Request - Within ICMP Message
• Type 8
• Code 0

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• Echo Reply
• The IP address (destination) of the ping,
  receives the ICMP message, Echo Request
• The ip address (destination) of the ping, returns
  the ICMP message, Echo Reply
• Echo Reply - Within ICMP Message
• Type 0
• Code 0

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Ping example
58
Pings may fail

• Q Are pings forwarded by routers?
• A Yes! This is why you can ping devices all
  over the Internet.
• Q Do all devices forward or respond to pings?
• A No, this is up to the network administrator of
  the device. Devices, including routers, can be
  configured not to reply to pings (ICMP echo
  requests). This is why you may not always be
  able to ping a device. Also, routers can be
  configured not to forward pings destined for
  other devices.

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Traceroute

• Traceroute is a utility that records the route
  (router IP addresses) between two devices on
  different networks.

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Tracroute

• http//en.wikipedia.org/wiki/Traceroute
• On modern Unix and Linux-based operating systems,
  the traceroute utility by default uses UDP
  datagrams with a destination port number starting
  at 33434.
• The traceroute utility usually has an option to
  specify use of ICMP echo request (type 8)
  instead.
• The Windows utility uses ICMP echo request,
  better known as ping packets.
• Some firewalls on the path being investigated may
  block UDP probes but allow the ICMP echo request
  traffic to pass through.
• There are also traceroute implementations sending
  out TCP packets, such as tcptraceroute or Layer
  Four Trace.
• In Microsoft Windows, traceroute is named
  tracert.
• A new utility, pathping, was introduced with
  Windows NT, combining ping and traceroute
  functionality. All these traceroutes rely on ICMP
  (type 11) packets coming back.

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Trace (Traceroute)

• Trace ( Cisco traceroute, tracert,) is used to
  trace the probable path a packet takes between
  source and destination.
• Probable, because IP is a connectionless
  protocol, and different packets may take
  different paths between the same source and
  destination networks, although this is not
  usually the case.
• Trace will show the path the packet takes to the
  destination, but the return path may be
  different.
• This is more likely the case in the Internet, and
  less likely within your own autonomous system.
• Linux/Unix Systems
• Uses ICMP message within an IP Packet
• Both are layer 3 protocols.
• Uses UDP as a the transport layer.
• We will see why this is important in a moment.

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Trace

• Format (trace, traceroute, tracert)
• RTA traceroute ip address
• RTA traceroute 192.168.10.2

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Trace

• How it works (using UDP) - Fooling the routers
  host!
• Traceroute uses ping (echo requests)
• Traceroute sets the TTL (Time To Live) field in
  the IP Header, initially to 1

64
Trace

• RTB - TTL
• When a router receives an IP Packet, it
  decrements the TTL by 1.
• If the TTL is 0, it will not forward the IP
  Packet, and send back to the source an ICMP time
  exceeded message.
• ICMP Message Type 11, Code 0

65

• RTB
• After the traceroute is received by the first
  router, it decrements the TTL by 1 to 0.
• Noticing the TTL is 0, it sends back a ICMP Time
  Exceeded message back to the source, using its IP
  address for the source IP address.
• Router Bs IP header includes its own IP address
  (source IP) and the sending hosts IP address
  (dest. IP).

66

• RTA, Sending Host
• The traceroute program of the sending host (RTA)
  will use the source IP address of this ICMP Time
  Exceeded packet to display at the first hop.
• RTA traceroute 192.168.10.2
• Type escape sequence to abort.
• Tracing the route to 192.168.10.2
• 1 10.0.0.2 4 msec 4 msec 4 msec

67

• RTA
• The traceroute program increments the TTL by 1
  (now 2 ) and resends the ICMP Echo Request
  packet.

68

• RTB
• This time RTB decrements the TTL by 1 and it is
  NOT 0. (It is 1.)
• So it looks up the destination ip address in its
  routing table and forwards it on to the next
  router.
• RTC
• RTC however decrements the TTL by 1 and it is 0.
• RTC notices the TTL is 0 and sends back the ICMP
  Time Exceeded message back to the source.
• RTCs IP header includes its own IP address
  (source IP) and the sending hosts IP address
  (destination IP address of RTA).
• The sending host, RTA, will use the source IP
  address of this ICMP Time Exceeded message to
  display at the second hop.

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RTA to RTB
RTB to RTC

• .

70

• The sending host, RTA
• The traceroute program uses this information
  (Source IP Address) and displays the second hop.
• RTA traceroute 192.168.10.2
• Type escape sequence to abort.
• Tracing the route to 192.168.10.2
• 1 10.0.0.2 4 msec 4 msec 4 msec
• 2 172.16.0.2 20 msec 16 msec 16 msec

71

• The sending host, RTA
• The traceroute program increments the TTL by 1
  (now 3 ) and resends the Packet.

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RTA to RTB
RTB to RTC

• .

RTC to RTD
73

• RTB
• This time RTB decrements the TTL by 1 and it is
  NOT 0. (It is 2.)
• So it looks up the destination ip address in its
  routing table and forwards it on to the next
  router.
• RTC
• This time RTC decrements the TTL by 1 and it is
  NOT 0. (It is 1.)
• So it looks up the destination ip address in its
  routing table and forwards it on to the next
  router.
• RTD
• RTD however decrements the TTL by 1 and it is 0.
• However, RTD notices that the Destination IP
  Address of 192.168.0.2 is its own interface.
• Since it does not need to forward the packet, the
  TTL of 0 has no affect.

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• RTD
• RTD sends the packet to the UDP process.
• UDP examines the unrecognizable port number of
  35,000 and sends back an ICMP Port Unreachable
  message to the sender, RTA, using Type 3 and Code
  3.

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• Sending host, RTA
• RTA receives the ICMP Port Unreachable message.
• The traceroute program uses this information
  (Source IP Address) and displays the third hop.
• The traceroute program also recognizes this Port
  Unreachable message as meaning this is the
  destination it was tracing.

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• Sending host, RTA
• RTA, the sending host, now displays the third
  hop.
• Getting the ICMP Port Unreachable message, it
  knows this is the final hop and does not send any
  more traces (echo requests).
• RTA traceroute 192.168.10.2
• Type escape sequence to abort.
• Tracing the route to 192.168.10.2
• 1 10.0.0.2 4 msec 4 msec 4 msec
• 2 172.16.0.2 20 msec 16 msec 16 msec
• 3 192.168.10.2 16 msec 16 msec 16 msec

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Chapter 6IPv4 Addresses Part 3

• CSIS 76 Networking Essentials
• Randy Arvay
• Monterey Peninsula College
• rarvay_at_mpc.edu