Transcript of Ip addressing
- 1. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 11 Computer NetworksComputer Networks (ECS - 601)(ECS -
601) BM KalraBM Kalra Professor and HoDProfessor and HoD Computer
Science and EngineeringComputer Science and Engineering Ajay Kumar
Garg Engineering College, GhaziabadAjay Kumar Garg Engineering
College, Ghaziabad
- 2. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 22 Lecture 33Lecture 33 (20 Mar 2015)(20 Mar 2015)
Network LayerNetwork Layer AddressingAddressing
- 3. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 33 OSI Model - Summary of layersOSI Model - Summary of
layers
- 4. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 44 Network LayerNetwork Layer Responsible for source to
destination delivery data link layerResponsible for source to
destination delivery data link layer oversees the delivery of
packet between two systems on the sameoversees the delivery of
packet between two systems on the same network (link)network (link)
To provide internetworking to move the packet through differentTo
provide internetworking to move the packet through different
networksnetworks Provides logical addressing IP Address network
layer adds aProvides logical addressing IP Address network layer
adds a header that includes the logical addresses of the sender and
theheader that includes the logical addresses of the sender and the
receiverreceiver Uses IP in TCP/IP protocol suiteUses IP in TCP/IP
protocol suite Delivery of individual packets from the source to
the destination hostDelivery of individual packets from the source
to the destination host A delivery mechanism used by TCP/UDPA
delivery mechanism used by TCP/UDP unreliable and connectionless
datagram protocolunreliable and connectionless datagram protocol
provides a best effort delivery serviceprovides a best effort
delivery service Provides no error control or flow controlProvides
no error control or flow control Only provides error detectionOnly
provides error detection IP supporting protocolsIP supporting
protocols ARP Address Resolution ProtocolARP Address Resolution
Protocol RARP Reverse Address Resolution ProtocolRARP Reverse
Address Resolution Protocol ICMP Internet Control Message
ProtocolICMP Internet Control Message Protocol IGMP Internet Group
Message ProtocolIGMP Internet Group Message Protocol
- 5. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 55 Links Between Two HostsLinks Between Two Hosts
- 6. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 66 Network layer in anNetwork layer in an
internetworkinternetwork
- 7. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 77 Network Layer at Source &Network Layer at Source
& DestinationDestination
- 8. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 88 Network Layer at the RouterNetwork Layer at the
Router
- 9. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 99 AddressingAddressing
- 10. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1010 AddressesAddresses AnalogyAnalogy If you want to
know any info about me fromIf you want to know any info about me
from somebody or want to send some info to mesomebody or want to
send some info to me How do you identify me?How do you identify me?
What is my identity?What is my identity? My NameMy Name My
AddressMy Address To send information on the net-To send
information on the net- whom to send?whom to send? How do you
identify a machine onHow do you identify a machine on the
network?the network?
- 11. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1111 AddressesAddresses FlatFlat voter-idvoter-id i-card
numbersi-card numbers HierarchicalHierarchical Postal PIN
numbersPostal PIN numbers International telephone
numberingInternational telephone numbering schemescheme What is a
MAC address?What is a MAC address?
- 12. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1212 Flat AddressingFlat Addressing In a flat routing
infrastructure, each network ID isIn a flat routing infrastructure,
each network ID is represented individually in the routing
table.represented individually in the routing table. The network
IDs have no network/subnet structureThe network IDs have no
network/subnet structure and cannot be summarized.and cannot be
summarized. RIP-based IPX internetworks use flat networkRIP-based
IPX internetworks use flat network addressing and have a flat
routing infrastructure.addressing and have a flat routing
infrastructure. .
- 13. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1313 IP Address HierarchyIP Address Hierarchy Does a
telephone switch in California know howDoes a telephone switch in
California know how to reach a specific phone in Virginia?to reach
a specific phone in Virginia? (1-703-555-1212)(1-703-555-1212)
- 14. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1414 IP Address HierarchyIP Address Hierarchy Does a
telephone switch in California know howDoes a telephone switch in
California know how to reach a specific phone in Virginia?to reach
a specific phone in Virginia? (1-703-555-1212)(1-703-555-1212) Long
(remote) distance Local office California Path to 1 (A number
indicates destination is remote)
- 15. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1515 Does a telephone switch in California know howDoes a
telephone switch in California know how to reach a specific phone
in Virginia?to reach a specific phone in Virginia?
(1-703-555-1212)(1-703-555-1212) Long (remote) distance Long
distance Virginia Path to 703 (An area code summarizes an area in
VA) Local office California Path to 1 (A number indicates
destination is remote) IP Address HierarchyIP Address
Hierarchy
- 16. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1616 Does a telephone switch in California know how
toDoes a telephone switch in California know how to reach a
specific phone in Virginia?reach a specific phone in Virginia?
(1-703-555-1212)(1-703-555-1212) Long (remote) distance Long
distance Virginia Path to 703 (An area code summarizes an area in
VA) Path to 555 (A prefix summarizes a smaller area in VA) Local
office Alexandria Local office California Path to 1 (A number
indicates destination is remote) IP Address HierarchyIP Address
Hierarchy
- 17. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1717 Does a telephone switch in California know how to
reach aDoes a telephone switch in California know how to reach a
specific phone in Virginia?specific phone in Virginia?
(1-703-555-1212)(1-703-555-1212) Long (Remote)- Distance
Long-Distance Virginia Path to 703 (An Area Code Summarizes an Area
in VA) Path to 555 (A Prefix Summarizes a Smaller Area in VA) Path
to 1212 (Number) Local Office Alexandria Local Office Aunt
JudyCalifornia Path to 1 (A Number Indicates Destination Is Remote)
IP Address HierarchyIP Address Hierarchy
- 18. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1818 Benefits of HierarchicalBenefits of Hierarchical
AddressingAddressing Reduced number of route table entriesReduced
number of route table entries Summarize multiple addresses into
routeSummarize multiple addresses into route summariessummaries
Efficient allocation of addressesEfficient allocation of addresses
Contiguous address assignment allows you toContiguous address
assignment allows you to use all possible addressesuse all possible
addresses
- 19. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 1919 Hierarchical AddressingHierarchical Addressing
groups of network IDs can be represented as a single routing table
entry through route summarization The network IDs in a hierarchical
internetwork have a network/subnet/sub-subnet structure A routing
table entry for the highest level (the network) is also the route
used for the subnets and sub-subnets of the network simplifes
routing tables and lower the amount of routing information that is
exchanged, but they require more planning IP implements
hierarchical network addressing, and IP internetworks can have a
hierarchical routing structure
- 20. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2020 AddressesAddresses Each communication endpoint
mustEach communication endpoint must have an address.have an
address. Consider 2 processesConsider 2 processes communicating
over an internet:communicating over an internet: the network must
be specifiedthe network must be specified the host must be
specifiedthe host must be specified the process must be
specified.the process must be specified.
- 21. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2121 AddressesAddresses Physical LayerPhysical Layer: no
address necessary: no address necessary Data Link LayerData Link
Layer - address must be able to- address must be able to select any
host on the network.select any host on the network. Network
LayerNetwork Layer - address must be able to- address must be able
to provide information to enable routing.provide information to
enable routing. Transport LayerTransport Layer - address must
identify the- address must identify the destination
process.destination process.
- 22. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2222 Addresses in TCP/IPAddresses in TCP/IP
- 23. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2323 AddressesAddresses Three typesThree types Port
AddressPort Address Layer 4 addressLayer 4 address For running
different applicationsFor running different applications Logical
AddressLogical Address Layer3 addressLayer3 address IP address and
it is set by the operating systemIP address and it is set by the
operating system Changes with location changeChanges with location
change Physical AddressPhysical Address Layer2 addressLayer2
address MAC addressMAC address generated by the
manufacturergenerated by the manufacturer The MAC address is unique
In a Local Area Network (LAN)The MAC address is unique In a Local
Area Network (LAN) Fixed does not changeFixed does not change
- 24. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2424 Logical & Physical AddressesLogical &
Physical Addresses AnalogyAnalogy My Name: Physical AddressMy Name:
Physical Address My Home Address: Logical AddressMy Home Address:
Logical Address
- 25. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2525
- 26. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2626 IPv4 AddressingIPv4 Addressing An IPv4 address is a
32-bit addressAn IPv4 address is a 32-bit address thatthat
uniquelyuniquely andand universallyuniversally definesdefines the
connection of a device (forthe connection of a device (for example,
a computer or a router) toexample, a computer or a router) to the
Internetthe Internet UniqueUnique two devices on the internet two
devices on the internet can never have the same address at thecan
never have the same address at the same timesame time
UniversalUniversal addressing system must be addressing system must
be accepted by any host that wants to beaccepted by any host that
wants to be connected to the Internetconnected to the Internet
- 27. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2727 IPv4 AddressingIPv4 Addressing Logical
AddressLogical Address Layer3 AddressingLayer3 Addressing Example -
IPv4/IPv6Example - IPv4/IPv6 IPv4 addresses are unique &
universalIPv4 addresses are unique & universal Two Level
Hierarchical AddressingTwo Level Hierarchical Addressing Network id
+ Host idNetwork id + Host id IPv4 32 bit addressing systemIPv4 32
bit addressing system 223232 = 4,294,967,296(more than 4 Billion IP
Addresses)= 4,294,967,296(more than 4 Billion IP Addresses) Network
IDNetwork ID (8 to 24 bits)(8 to 24 bits) Host IDHost ID (24 to 8
bits)(24 to 8 bits)
- 28. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2828 IPv4 /Internet/Global /LogicalIPv4 /Internet/Global
/Logical AddressAddress
- 29. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 2929 The IPv4 addresses are unique and universal.
NoteNote
- 30. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3030 The address space of IPv4 is 232 or 4,294,967,296
(more than 4 billion) NoteNote
- 31. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3131 Layer 3 AddressesLayer 3 Addresses Network IDNetwork
ID Assigned byAssigned by ARINARIN (www.arin.net)(www.arin.net)
Identifies theIdentifies the network tonetwork to which a
devicewhich a device is attached.is attached. May beMay be
identified byidentified by one, two, orone, two, or three of
thethree of the first threefirst three octets.octets. Host IDHost
ID Assigned by aAssigned by a networknetwork
administrator.administrator. Identifies the specificIdentifies the
specific device on thatdevice on that network.network. May be
identified byMay be identified by one, two, or three ofone, two, or
three of the last three octets.the last three octets.
- 32. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3232 IP Address: NotationIP Address: Notation Binary
NotationBinary Notation In binary notation, the IPv4 address is
displayed as 32 bits.In binary notation, the IPv4 address is
displayed as 32 bits. Each octet is often referred to as a byte. So
it is common to hear anEach octet is often referred to as a byte.
So it is common to hear an IPv4 address referred to as a 32-bit
address or a 4-byte address. (MACIPv4 address referred to as a
32-bit address or a 4-byte address. (MAC Address 6 bytes)Address 6
bytes) The following is an example of an IPv4 address in binary
notation:The following is an example of an IPv4 address in binary
notation: 01110101 10010101 00011101 0000001001110101 10010101
00011101 00000010 Dotted-Decimal NotationDotted-Decimal Notation To
make the IPv4 address more compact and easier to read, InternetTo
make the IPv4 address more compact and easier to read, Internet
addresses are usually written in decimal form with a decimal
pointaddresses are usually written in decimal form with a decimal
point (dot) separating the bytes.(dot) separating the bytes. The
following is the dotted-decimal notation of the above address:The
following is the dotted-decimal notation of the above address:
117.149.29.2117.149.29.2 One octet 8 bitsOne octet 8 bits total
numbers 2total numbers 288 =256 (0-255)=256 (0-255) So, highest
number 255So, highest number 255
- 33. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3333 Dotted-decimal notation andDotted-decimal notation
and binary notation for an IPv4binary notation for an IPv4
addressaddress
- 34. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3434 Dotted - Decimal NotationDotted - Decimal Notation
Network layer addresses are 32 bits longNetwork layer addresses are
32 bits long
1000010010100011100000000001000110000100101000111000000000010001
This binary number can be divided into fourThis binary number can
be divided into four octetsoctets 10000100 10100011 10000000
0001000110000100 10100011 10000000 00010001 Each octet (or byte)
can be converted toEach octet (or byte) can be converted to decimal
numberdecimal number 132 163 128 17132 163 128 17 Finally the
address can be written in dottedFinally the address can be written
in dotted decimal notationdecimal notation
132.163.128.17132.163.128.17
- 35. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3535 Example 19.1Example 19.1 Change the following IPv4
addresses fromChange the following IPv4 addresses from binary
notation to dotted-decimal notation.binary notation to
dotted-decimal notation. SolutionSolution We replace each group of
8 bits with itsWe replace each group of 8 bits with its equivalent
decimal number and add dots forequivalent decimal number and add
dots for separation.separation.
- 36. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3636 Example 19.2Example 19.2 Change the following IPv4
addresses fromChange the following IPv4 addresses from
dotted-decimal notation to binary notation.dotted-decimal notation
to binary notation. SolutionSolution We replace each decimal number
with itsWe replace each decimal number with its binary
equivalentbinary equivalent
- 37. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3737 Example 19.3Example 19.3 Find the error, if any, in
the following IPv4 addresses.Find the error, if any, in the
following IPv4 addresses. a.a. 111.56.045.78111.56.045.78 b.b.
221.34.7.8.20221.34.7.8.20 c.c. 75.45.301.1475.45.301.14 d.d.
11100010.23.14.6711100010.23.14.67 SolutionSolution a.a. There must
be no leading zero (There must be no leading zero (0045).45). b.b.
There can be no more than four numbers.There can be no more than
four numbers. c.c. Each number needs to be less than or equal to
255.Each number needs to be less than or equal to 255. d.d. A
mixture of binary notation and dotted-decimalA mixture of binary
notation and dotted-decimal notation is not allowed.notation is not
allowed.
- 38. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 3939 Classful IP AddressesClassful IP Addresses Three
major organizationsThree major organizations Large
OrganizationLarge Organization with a largewith a large number of
attached hosts or routersnumber of attached hosts or routers
Midsize organizationMidsize organization with tens andwith tens and
thousands of attached hosts orthousands of attached hosts or
routersrouters Small organizationSmall organization with a
smallwith a small number of attached hosts or routersnumber of
attached hosts or routers
- 39. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4040 In classful addressing, the address space is divided
into five classes: A, B, C, D, and E. NoteNote
- 40. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4141 Classful IP AddressesClassful IP Addresses Three
major classesThree major classes Class AClass A: Small number of
Networks: Small number of Networks Large number of hosts Large
number of hosts Class BClass B: Medium number of: Medium number of
Networks Medium number of hostsNetworks Medium number of hosts
Class CClass C: Large number of Networks: Large number of Networks
Small number of hosts Small number of hosts
- 41. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4242 Classful IP AddressesClassful IP Addresses N
NetworkN Network H HostH Host FirstFirst OctetOctet SecondSecond
OctetOctet ThirdThird OctetOctet FourthFourth OctetOctet Class
AClass A NN HH HH HH Class BClass B NN NN HH HH Class CClass C NN
NN NN HH Class DClass D Class EClass E
- 42. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4343 Classes Binary & DottedClasses Binary &
Dotted DecimalDecimal Class D: for multicastingClass D: for
multicasting Class E: for future/research useClass E: for
future/research use
- 43. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4444 First OctetFirst Octet Class AClass A 00
00000000000000 00 00 11111111111111 127127 Class BClass B 1010
000000000000 128128 1010 111111111111 191191 Class CClass C 110110
0000000000 192192 110110 1111111111 223223 Class D:Class D:
MulticastMulticast 11101110 00000000 224224 11101110 11111111
239239 Class E:Class E: ExperimentalExperimental 11111111 00000000
240240 11111111 11111111 255255
- 44. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4545 Address Class UsageAddress Class Usage
AddressAddress classes A, B, and Cclasses A, B, and C are available
forare available for Internet useInternet use Class DClass D
addresses are used foraddresses are used for
multicastingmulticasting Some Class D multicast addresses areSome
Class D multicast addresses are used byused by routing
protocolsrouting protocols OSPF224.0.0.5, 224.0.0.6OSPF224.0.0.5,
224.0.0.6 RIPv2224.0.0.9RIPv2224.0.0.9
EIGRP224.0.0.10EIGRP224.0.0.10 Other Class D multicast addresses
are used byOther Class D multicast addresses are used by
videoconferencing or other applicationsvideoconferencing or other
applications Class EClass E addresses are reserved for future
useaddresses are reserved for future use and for research
purposesand for research purposes
- 45. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4646 What Class?What Class? How do you know what class an
IP address is in?How do you know what class an IP address is in?
For Dotted Decimal AddressFor Dotted Decimal Address If the first
octet is between:If the first octet is between: 0 1270 127 Class A
addressesClass A addresses 128 191128 191 Class B AddressesClass B
Addresses 192 223192 223 Class C AddressesClass C Addresses 224
239224 239 Class D AddressesClass D Addresses 240 255240 255 Class
E AddressesClass E Addresses For Binary IP AddressFor Binary IP
Address The first bit is 0The first bit is 0 Class A AddressClass A
Address The first 2 bits are 10The first 2 bits are 10 Class B
AddressClass B Address First three bits are 110First three bits are
110 Class C AddressClass C Address First four bits are 1110First
four bits are 1110 Class D AddressClass D Address First four bits
are 1111First four bits are 1111 Class E AddressClass E
Address
- 46. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4747 Example 19.4Example 19.4 Find the class of each
addressFind the class of each address a.a. 000000001 00001011
00001011 111011110000001 00001011 00001011 11101111 b.b.
11011000001 10000011 00011011 1111111100001 10000011 00011011
11111111 c.c. 1414.23.120.8.23.120.8 d.d. 252252.5.15.111.5.15.111
SolutionSolution a.a. The first bit is 0. This is a class A
address.The first bit is 0. This is a class A address. b.b. The
first 2 bits are 1; the third bit is 0. This is a class CThe first
2 bits are 1; the third bit is 0. This is a class C
address.address. c.c. The first byte is 14; the class is A.The
first byte is 14; the class is A. d.d. The first byte is 252; the
class is E.The first byte is 252; the class is E.
- 47. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4848 Number of NetworksNumber of Networks Number of
networks in each classNumber of networks in each class Class A has
128 networks (0 to 127)Class A has 128 networks (0 to 127) Class B
has 16,384 networksClass B has 16,384 networks Class C has
2,097,152 networksClass C has 2,097,152 networks
- 48. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 4949 Number of HostsNumber of Hosts Maximum number of
hosts vary for eachMaximum number of hosts vary for each classclass
Class A has 16,777,214 available hosts (2Class A has 16,777,214
available hosts (22424 2)2) Class B has 65,534 available hosts
(2Class B has 65,534 available hosts (21616 2)2) Class C has 254
available hosts (2Class C has 254 available hosts (288 2)2) The
first address in each network isThe first address in each network
is reserved for thereserved for the Network AddressNetwork Address
(all zeros)(all zeros) and the last address is reserved for theand
the last address is reserved for the Broadcast AddressBroadcast
Address (all ones)(all ones)
- 49. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5050 No. of blocks and block sizeNo. of blocks and block
size
- 50. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5151 In classful addressing, a large part of the
available addresses were wasted. NoteNote
- 51. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5252 Lecture 34Lecture 34 (20 Mar 2015)(20 Mar 2015) IP
AddressingIP Addressing
- 52. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5353 Reserved AddressesReserved Addresses Network Address
(wire address)Network Address (wire address) This is an This is an
IP address that ends with binaryIP address that ends with binary 0s
in all0s in all host bits.host bits. Class A Network Address
example:Class A Network Address example: 113.0.0.0113.0.0.0 Hosts
on a network can only communicateHosts on a network can only
communicate directlydirectly with other hosts if they have thewith
other hosts if they have the same network ID.same network ID. If
they dont, they will not be able toIf they dont, they will not be
able to communicate unless there iscommunicate unless there is
another deviceanother device connecting the networks.connecting the
networks.
- 53. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5454 Reserved AddressesReserved Addresses Broadcast
AddressBroadcast Address is used to send data is used to send data
to all of the devices on a network.to all of the devices on a
network. Broadcast IP addresses end with binaryBroadcast IP
addresses end with binary 1s1s in the host partin the host part of
the address.of the address. Class B Broadcast Address example:Class
B Broadcast Address example: 176.10.255.255176.10.255.255 (Remember
decimal 255 = binary 11111111)(Remember decimal 255 = binary
11111111)
- 54. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5555 Special AddressSpecial Address Host ID all 0s is
reserved to refer toHost ID all 0s is reserved to refer to
networknetwork numbernumber 192.168.100.0192.168.100.0
158.108.0.0158.108.0.0 18.0.0.018.0.0.0 Host ID all 1s is reserved
toHost ID all 1s is reserved to broadcastbroadcast to allto all
hosts on a specific networkhosts on a specific network
192.168.100.255192.168.100.255 158.108.255.255158.108.255.255
18.255.255.25518.255.255.255 Address 0.0.0.0 means Address 0.0.0.0
means default routedefault route Address 127.0.0.0 means Address
127.0.0.0 means this nodethis node Address 127.0.0.1Address
127.0.0.1 ((local loopbacklocal loopback). Message sent). Message
sent to this address will never leave the local hostto this address
will never leave the local host Address 255.255.255.255 is
reserveAddress 255.255.255.255 is reservedd to broadcastto
broadcast to every host on the local network (limitedto every host
on the local network (limited broadcast)broadcast)
- 55. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5656 Netid and HostidNetid and Hostid Netid and host id
are of varying length Netid and host id are of varying length
depending on class of the addressdepending on class of the address
FirstFirst OctetOctet SecondSecond OctetOctet ThirdThird OctetOctet
FourthFourth OctetOctet Class AClass A NN HH HH HH Class BClass B
NN NN HH HH Class CClass C NN NN NN HH Class DClass D Class EClass
E
- 56. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5757 Netid and HostidNetid and Hostid
- 57. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5858 MaskMask Although the length of the netid and hostid
(inAlthough the length of the netid and hostid (in bits) is
predetermined in classful addressing,bits) is predetermined in
classful addressing, we can also use a mask (also called the
defaultwe can also use a mask (also called the default mask), a
32-bit number made of contiguous 1smask), a 32-bit number made of
contiguous 1s followed by contiguous 0s.followed by contiguous 0s.
The mask can help us to find the netid and theThe mask can help us
to find the netid and the hostid.hostid. For example, the mask for
a class A address hasFor example, the mask for a class A address
has eight 1s, which means the first 8 bits of anyeight 1s, which
means the first 8 bits of any address in class A define the netid;
the next 24address in class A define the netid; the next 24 bits
define the hostid.bits define the hostid. The concept does not
apply to classes D and E.The concept does not apply to classes D
and E.
- 58. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 5959 MaskingMasking
- 59. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 6060 Default Mask for classfulDefault Mask for classful
addressingaddressing The last column shows the mask in the form
/nThe last column shows the mask in the form /n where n can be 8,
16, or 24 in classful addressing.where n can be 8, 16, or 24 in
classful addressing. This notation is also calledThis notation is
also called slash notationslash notation oror Classless Interdomain
RoutingClassless Interdomain Routing (CIDR) notation.(CIDR)
notation. Classful addressing is a special case of
classlessClassful addressing is a special case of classless
addressing.addressing.
- 60. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 6161 IP AddressingIP Addressing Crisis &
SolutionsCrisis & Solutions
- 61. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 6262 Flaw in Classful AddressFlaw in Classful Address We
can see the flaw in this design.We can see the flaw in this design.
A block in class A address is too large forA block in class A
address is too large for almost any organizationalmost any
organization A block in class B is also very large,A block in class
B is also very large, probably too large for any of theprobably too
large for any of the organizations that received a class B
block.organizations that received a class B block. A block in class
C is probably too small.A block in class C is probably too small. A
and B always wasted. But C is always notA and B always wasted. But
C is always not enuff!!!enuff!!!
- 62. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 6565 Issues with IP AddressingIssues with IP Addressing
IP address exhaustionIP address exhaustion Routing table
growthRouting table growth U N I V E R S I T YU N I V E R S I T Y
Internet
- 63. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 6666 IP Addressing SolutionsIP Addressing Solutions
SubnettingSubnetting (RFCs 950, 1812)(RFCs 950, 1812) Private
AddressesPrivate Addresses (RFC 1918)(RFC 1918) Network Address
Translation (NAT)Network Address Translation (NAT) (RFC 1631)(RFC
1631) Classless Interdomain Routing (CIDR)Classless Interdomain
Routing (CIDR) (RFCs 1518, 1519, 2050)(RFCs 1518, 1519, 2050) Route
summarizationRoute summarization (RFC 1518)(RFC 1518) Variable
Length Subnet MaskingVariable Length Subnet Masking (VLSM)(VLSM)
(RFC 1812)(RFC 1812)
- 64. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 6767 SubnettingSubnetting
- 65. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 6868 Basics of SubnettingBasics of Subnetting Subnetwork
is a smaller divisions of a networksSubnetwork is a smaller
divisions of a networks A larger network is split into several
smaller partsA larger network is split into several smaller parts
for internal use say different departments of afor internal use say
different departments of a college but still act like a single
network to thecollege but still act like a single network to the
outside worldoutside world
- 66. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 6969 SubnettingSubnetting Basically without subnetting,
most ofBasically without subnetting, most of organization is
limited to two levelsorganization is limited to two levels of
hierarchyof hierarchy In this case, the hosts cannot beIn this
case, the hosts cannot be organized into groups, and all of
theorganized into groups, and all of the hosts are at the same
level.hosts are at the same level. As a result the organization has
oneAs a result the organization has one network with many many
hostsnetwork with many many hosts
- 67. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7070 A Network with Two Levels ofA Network with Two
Levels of HierarchyHierarchy
- 68. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7171 To make a network more organize,To make a network
more organize, three levels of hierarchy isthree levels of
hierarchy is implemented.implemented. Subnetting creates an
intermediateSubnetting creates an intermediate level of hierarchy
in the IP addressinglevel of hierarchy in the IP addressing
system.system. Now we have 3 levels:Now we have 3 levels:
NetidNetid subnetid, andsubnetid, and hostid.hostid.
SubnettingSubnetting
- 69. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7272 Subnet AddressesSubnet Addresses Changing from 2
Level hierarchy to 3 LevelChanging from 2 Level hierarchy to 3
Level hierarchyhierarchy Include Class A, B, or C network portion
plus aInclude Class A, B, or C network portion plus a subnet field
and a host field.subnet field and a host field. Bits are borrowed
from the host field and areBits are borrowed from the host field
and are designated as the subnet field.designated as the subnet
field. NetworkNetwork SubnetSubnet HostHost NetworkNetwork
HostHost
- 70. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7373 A Network with Three Levels ofA Network with Three
Levels of HierarchyHierarchy
- 71. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7474 Basics of SubnettingBasics of Subnetting They
provide addressing flexibilityThey provide addressing flexibility
Less wastage of IP addressesLess wastage of IP addresses Better
logical organizationBetter logical organization Provides a logical
network structure thatProvides a logical network structure that is
hidden from the outside worldis hidden from the outside world
A.K.A. subnetsA.K.A. subnets Subnet addresses are assigned
locally,Subnet addresses are assigned locally, usually by a network
administrator.usually by a network administrator. Subnets reduce a
broadcast domain.Subnets reduce a broadcast domain. RFC 950
(1985)RFC 950 (1985)
- 72. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7575 SupernettingSupernetting The time came when most of
the class A and class BThe time came when most of the class A and
class B addresses were depleted; however, here was still aaddresses
were depleted; however, here was still a huge demand for midsize
blocks.huge demand for midsize blocks. The size of a class C block
with a maximum number ofThe size of a class C block with a maximum
number of 256 addresses did not satisfy the needs of most256
addresses did not satisfy the needs of most
organizations.organizations. Even a midsize organization needed
more addresses.Even a midsize organization needed more addresses.
One solution was supernetting.One solution was supernetting. In
supernetting, an organization can combine severalIn supernetting,
an organization can combine several class C blocks to create a
larger range of addresses.class C blocks to create a larger range
of addresses. In other words, several networks are combined toIn
other words, several networks are combined to create a supernetwork
or a supernet.create a supernetwork or a supernet.
- 73. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7676 SupernettingSupernetting An organization can apply
for a set of class C blocksAn organization can apply for a set of
class C blocks instead of just one.instead of just one. For
example, an organization that needs 1000For example, an
organization that needs 1000 addresses can be granted four
contiguous class Caddresses can be granted four contiguous class C
blocks.blocks. The organization can then use these addresses toThe
organization can then use these addresses to create one
supernetwork.create one supernetwork. Supernetting decreases the
number of 1s in the mask.Supernetting decreases the number of 1s in
the mask. For example, if an organization is given four class CFor
example, if an organization is given four class C addresses, the
mask changes from /24 to /22.addresses, the mask changes from /24
to /22. We will see that classless addressing eliminated theWe will
see that classless addressing eliminated the need for
supernetting.need for supernetting.
- 74. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7777 Addresses with and withoutAddresses with and without
SubnettingSubnetting
- 75. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7878 Subnet MaskSubnet Mask To implement subnetting,
mainTo implement subnetting, main router needs a subnet mask
thatrouter needs a subnet mask that indicates the network +
subnetindicates the network + subnet portion and the host
portionportion and the host portion Subnet mask is also 32 bit
longSubnet mask is also 32 bit long Written in dotted decimal
notationWritten in dotted decimal notation with a slash followed by
the numberwith a slash followed by the number of bits in the
network + subnet partof bits in the network + subnet part
- 76. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 7979 Subnet MaskSubnet Mask Subnet mask can be written
asSubnet mask can be written as 255.255.252.0255.255.252.0
Alternative notationAlternative notation /22/22 indicates indicates
that the subnet mask is 22 bit longthat the subnet mask is 22 bit
long
- 77. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8080 Classful addressing, which is almost obsolete, is
replaced with classless addressing. Note
- 78. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8181 ClasslessClassless Interdomain Routing
(CIDR)Interdomain Routing (CIDR) cidercider
- 79. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8282 Classless AddressingClassless Addressing To overcome
address depletion and give more organizationsTo overcome address
depletion and give more organizations access to the Internet,
classless addressing was designed andaccess to the Internet,
classless addressing was designed and implemented.implemented. In
this scheme,In this scheme, there are no classesthere are no
classes, but the addresses are still, but the addresses are still
granted in blocks.granted in blocks. Address BlocksAddress Blocks
In classless addressing, when an entity, small or large, needsIn
classless addressing, when an entity, small or large, needs to be
connected to the Internet, it is granted a block (range) ofto be
connected to the Internet, it is granted a block (range) of
addresses.addresses. The size of the block (the number of
addresses) varies basedThe size of the block (the number of
addresses) varies based on the nature and size of the entity.on the
nature and size of the entity. For example,For example, a household
may be given only two addresses;a household may be given only two
addresses; a large organization may be given thousands of
addressesa large organization may be given thousands of addresses
an ISP, as the Internet service provider, may be given thousandsan
ISP, as the Internet service provider, may be given thousands or
hundreds of thousands based on the number of customers itor
hundreds of thousands based on the number of customers it may
serve.may serve.
- 80. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8383 Classless AddressingClassless Addressing To simplify
the handling of addresses,To simplify the handling of addresses,
the Internet authorities impose threethe Internet authorities
impose three restrictions on classless addressrestrictions on
classless address blocks:blocks: 1. The addresses in a block must
be1. The addresses in a block must be contiguous, one after
another.contiguous, one after another. 2. The number of addresses
in a block2. The number of addresses in a block must be a power of
2 (I, 2, 4, 8, ... ).must be a power of 2 (I, 2, 4, 8, ... ). 3.
The first address must be evenly3. The first address must be evenly
divisible by the number of addresses.divisible by the number of
addresses.
- 81. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8484 Example 19.5Example 19.5 Figure 19.3 shows a block
ofFigure 19.3 shows a block of addresses, in both binary and
dotted-addresses, in both binary and dotted- decimal notation,
granted to a smalldecimal notation, granted to a small business
that needs 16 addresses.business that needs 16 addresses.
- 82. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8585 Example 19.5Example 19.5 Figure 19.3, A block of 16
addresses granted to a small organizationFigure 19.3, A block of 16
addresses granted to a small organization We can see that the
restrictions are applied to this block.We can see that the
restrictions are applied to this block. The addresses are
contiguous.The addresses are contiguous. The number of addresses is
a power of 2 (16 = 24), andThe number of addresses is a power of 2
(16 = 24), and The first address is divisible by 16.The first
address is divisible by 16. The first address, when converted to a
decimal number, isThe first address, when converted to a decimal
number, is 3,440,387,360, which when divided by 16 results in
215,024,2103,440,387,360, which when divided by 16 results in
215,024,210
- 83. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8686 MaskMask A better way to define a block of addresses
isA better way to define a block of addresses is to select any
address in the block and theto select any address in the block and
the mask.mask. As we discussed before, a mask is a 32-bitAs we
discussed before, a mask is a 32-bit number in which thenumber in
which the n leftmost bits are 1sn leftmost bits are 1s and the 32 -
n rightmost bits are 0s.and the 32 - n rightmost bits are 0s.
However, in classless addressing the maskHowever, in classless
addressing the mask for a block can take any value from 0 to 32.for
a block can take any value from 0 to 32. It is very convenient to
give just the value ofIt is very convenient to give just the value
of n preceded by a slash (CIDR notation).n preceded by a slash
(CIDR notation).
- 84. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8787 MaskMask In IPv4 addressing, a block ofIn IPv4
addressing, a block of addresses can be defined asaddresses can be
defined as x.y.z.t /x.y.z.t /nn in which x.y.z.t defines one of
thein which x.y.z.t defines one of the addresses and the /addresses
and the /nn defines the maskdefines the mask Where n is the number
of 1s in the maskWhere n is the number of 1s in the mask
NoteNote
- 85. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8888 MaskMask The address and the /n notationThe address
and the /n notation completely define the whole block
(thecompletely define the whole block (the first address, the last
address, and thefirst address, the last address, and the number of
addresses).number of addresses). First Address:First Address:
Network AddressNetwork Address (host part 0s)(host part 0s) The
first address in the block can beThe first address in the block can
be found by setting thefound by setting the (32 n) rightmost(32 n)
rightmost bitsbits in the binary notation of thein the binary
notation of the address toaddress to 0s0s..
- 86. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 8989 MaskMask The first address in the block can be found
by setting the rightmost 32 n bits to 0s. NoteNote
- 87. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9090 Example 19.6Example 19.6 A block of addresses is
granted to a smallA block of addresses is granted to a small
organization. We know that one of the addresses isorganization. We
know that one of the addresses is 205.16.37.39/28205.16.37.39/28.
What is the first address in the. What is the first address in the
block?block? SolutionSolution The binary representation of the
given address isThe binary representation of the given address is
11001101 00010000 00100101 0010011111001101 00010000 00100101
00100111 If we set 3228 rightmost bits to 0, we getIf we set 3228
rightmost bits to 0, we get 11001101 00010000 00100101
001000011001101 00010000 00100101 0010000 oror
205.16.37.32205.16.37.32 This is actually the block shown in Figure
19.3.This is actually the block shown in Figure 19.3.
- 88. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9191 Last Address:Last Address: Broadcast Address (host
part 1s)Broadcast Address (host part 1s) The last address in the
block can beThe last address in the block can be found by setting
thefound by setting the (32 n) rightmost(32 n) rightmost bitsbits
in the binary notation of thein the binary notation of the address
toaddress to 1s1s..
- 89. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9292 The last address in the block can be found by
setting the rightmost 32 n bits to 1s. NoteNote
- 90. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9393 Example 19.7Example 19.7 Find the last addressFind
the last address for the block in Example 19.6. A block of
addresses is granted to a small organization.A block of addresses
is granted to a small organization. We know that one of the
addresses isWe know that one of the addresses is
205.16.37.39/28205.16.37.39/28.. What is the first address in the
block?What is the first address in the block? Solution The binary
representation of the given address is 11001101 00010000 00100101
00100111 If we set 32 28 rightmost bits to 1, we get 11001101
00010000 00100101 00101111 or 205.16.37.47 This is actually the
block shown in Figure 19.3.
- 91. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9494 Number of AddressesNumber of Addresses The number of
addresses in theThe number of addresses in the block is the
difference between theblock is the difference between the last and
first address.last and first address. It can easily be found using
theIt can easily be found using the formulaformula 2232- n32- n
..
- 92. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9595 The number of addresses in the block can be found by
using the formula 232n . NoteNote
- 93. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9696 Example 19.8Example 19.8 Find the number of
addresses in ExampleFind the number of addresses in Example
19.6.19.6. A block of addresses is granted to a smallA block of
addresses is granted to a small organization. We know that one of
theorganization. We know that one of the addresses isaddresses is
205.16.37.39/28205.16.37.39/28. What is the first. What is the
first address in the block?address in the block? SolutionSolution
formulaformula 2232- n32- n The value of n is 28, which means
thatThe value of n is 28, which means that number of addresses is
2number of addresses is 2 32283228 or 16.or 16.
- 94. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9797 Example 19.9Example 19.9 Another way to find the
first address, the lastAnother way to find the first address, the
last address, and the number of addresses is toaddress, and the
number of addresses is to represent the mask as arepresent the mask
as a 32-bit binary32-bit binary (or 8-digit(or 8-digit hexadecimal)
number.hexadecimal) number. This is particularly useful when we are
writing aThis is particularly useful when we are writing a program
to find these pieces of information.program to find these pieces of
information. In Example 19.5 the /28 can be represented asIn
Example 19.5 the /28 can be represented as 11111111 11111111
11111111 1111000011111111 11111111 11111111 11110000 (twenty-eight
1s and four 0s).(twenty-eight 1s and four 0s). FindFind a.a. The
first addressThe first address b.b. The last addressThe last
address c.c. The number of addresses.The number of addresses.
- 95. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9898 Solution a. The first address can be found by ANDing
the given addresses with the mask. ANDing here is done bit by bit.
The result of ANDing 2 bits is 1 if both bits are 1s; the result is
0 otherwise.
- 96. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 9999 b.The last address can be found by ORing the given
addresses with the complement of the mask. ORing here is done bit
by bit. The result of ORing 2 bits is 0 if both bits are 0s; the
result is 1 otherwise. The complement of a number is found by
changing each 1to 0 and each 0 to 1.
- 97. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 100100 c. The number of addresses can be found by
complementing the mask, interpreting it as a decimal number, and
adding 1 to it.
- 98. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 101101 Lecture 35Lecture 35 (1 4Mar 2014)(1 4Mar 2014) IP
AddressingIP Addressing
- 99. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 102102 Network AddressesNetwork Addresses When an
organization is given a block ofWhen an organization is given a
block of addresses, the organization is free to allocate
theaddresses, the organization is free to allocate the addresses to
the devices that need to beaddresses to the devices that need to be
connected to the Internet.connected to the Internet. The first
address in the class, however, isThe first address in the class,
however, is normally (not always) treated as a specialnormally (not
always) treated as a special address.address. TheThe first address
is called the network addressfirst address is called the network
address andand defines the organization networkdefines the
organization network.. It defines the organization itself to the
rest of theIt defines the organization itself to the rest of the
world.world. The first address is the one that isThe first address
is the one that is used byused by routers to direct the message
sent to therouters to direct the message sent to the
organizationorganization from the outside.from the outside.
- 100. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 103103 The first address in a block is normally not
assigned to any device; it is used as the network address that
represents the organization to the rest of the world. Note
- 101. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 104104 Figure 19.5 Two levels of hierarchy in an IPv4
address
- 102. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 105105 Two-Level Hierarchy: NoTwo-Level Hierarchy: No
SubnettingSubnetting An IP address can define only two levels of
hierarchyAn IP address can define only two levels of hierarchy when
not subnetted.when not subnetted. PrefixPrefix: The part of the
address that defines the: The part of the address that defines the
network is called the prefix - Thenetwork is called the prefix -
The n leftmost bitsn leftmost bits ofof the address x.y.z.t/n
define the network (organizationthe address x.y.z.t/n define the
network (organization network)network) SuffixSuffix: the part that
defines the host is called the: the part that defines the host is
called the suffix - thesuffix - the (32-n)(32-n) rightmost bits
define the particularrightmost bits define the particular host
(computer or router) to the network.host (computer or router) to
the network.
- 103. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 106106 Each address in the block can be considered as a
two-level hierarchical structure: the leftmost n bits (prefix)
define the network; the rightmost 32 n (suffix) bits define the
host. NoteNote
- 104. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 107107 Three-Levels of Hierarchy:Three-Levels of
Hierarchy: SubnettingSubnetting An organization that is granted a
large block ofAn organization that is granted a large block of
addresses may want to create clusters of networksaddresses may want
to create clusters of networks (called subnets) and divide the
addresses between(called subnets) and divide the addresses between
the different subnets.the different subnets. The rest of the world
still sees the organization asThe rest of the world still sees the
organization as one entity; however, internally there are
severalone entity; however, internally there are several
subnets.subnets. All messages are sent to the router address
thatAll messages are sent to the router address that connects the
organization to the rest of the Internet;connects the organization
to the rest of the Internet; the router routes the message to the
appropriatethe router routes the message to the appropriate
subnets.subnets. The organization, however, needs to create small
subThe organization, however, needs to create small sub blocks of
addresses, each assigned to specificblocks of addresses, each
assigned to specific subnets.subnets. The organization has its own
mask;The organization has its own mask; each subneteach subnet must
also have its own mask.must also have its own mask.
- 105. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 108108 Three-Level Hierarchy in an IPv4Three-Level
Hierarchy in an IPv4 AddressAddress subnet prefix length can differ
for thesubnet prefix length can differ for the subnetssubnets
- 106. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 109109 ExampleExample suppose an organization is given
the block 17.12.40.0/26,suppose an organization is given the block
17.12.40.0/26, which contains 64 addresses.which contains 64
addresses. The organization has three offices and needs to divide
theThe organization has three offices and needs to divide the
addresses into three sub blocks of 32, 16, and 16
addresses.addresses into three sub blocks of 32, 16, and 16
addresses. SolutionSolution We canWe can find the new masksfind the
new masks by using the following arguments:by using the following
arguments: 1. Suppose the mask for the first subnet is n1, then 21.
Suppose the mask for the first subnet is n1, then 232- n132- n1
must bemust be 32, which means that n1 =27.32, which means that n1
=27. 2. Suppose the mask for the second subnet is n2, then 22.
Suppose the mask for the second subnet is n2, then 232- n232- n2
mustmust be 16, which means that n2 = 28.be 16, which means that n2
= 28. 3. Suppose the mask for the third subnet is n3, then 23.
Suppose the mask for the third subnet is n3, then 232- n332- n3
must bemust be 16, which means that n3 =28.16, which means that n3
=28. This means that we have the masksThis means that we have the
masks 27, 28, 2827, 28, 28 with thewith the organization mask
beingorganization mask being 2626.. Figure shows one configuration
for the above scenario.Figure shows one configuration for the above
scenario. Three-Levels of Hierarchy:Three-Levels of Hierarchy:
SubnettingSubnetting
- 107. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 110110 Configuration & Addresses:
SubnettedConfiguration & Addresses: Subnetted
NetworkNetwork
- 108. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 111111 Finding subnet addresses from oneFinding subnet
addresses from one of the addresses in the subnet.of the addresses
in the subnet. In subnet 1In subnet 1, the address 17.12.14.29/27
can, the address 17.12.14.29/27 can give us the subnet address if
we use thegive us the subnet address if we use the subnet mask
/27subnet mask /27 HostHost:: 00010001 00001100 00001110
0001110100010001 00001100 00001110 00011101 ANDing with MaskANDing
with Mask: /27 (27 1s): /27 (27 1s) 11111111 11111111 11111111
1110000011111111 11111111 11111111 11100000 We get theWe get the
subnetsubnet:: 00010001 00001100 00001110 0000000000010001 00001100
00001110 00000000 17.12.14.017.12.14.0
- 109. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 112112 Finding subnet addresses from oneFinding subnet
addresses from one of the addresses in the subnet.of the addresses
in the subnet. In subnet 2In subnet 2, the address 17.12.14.45/28
can, the address 17.12.14.45/28 can give us the subnet address if
we use thegive us the subnet address if we use the subnet mask
/28subnet mask /28 HostHost:: 00010001 00001100 00001110
0010110100010001 00001100 00001110 00101101 ANDing with MaskANDing
with Mask: /28 (28 1s): /28 (28 1s) 11111111 11111111 11111111
1111000011111111 11111111 11111111 11110000 We get the subnetWe get
the subnet:: 00010001 00001100 00001110 0010000000010001 00001100
00001110 00100000 17.12.14.3217.12.14.32
- 110. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 113113 Finding subnet addresses from oneFinding subnet
addresses from one of the addresses in the subnet.of the addresses
in the subnet. In subnet 3In subnet 3, the address 17.12.14.50/28
can, the address 17.12.14.50/28 can give us the subnet address if
we use thegive us the subnet address if we use the subnet mask /28
becausesubnet mask /28 because HostHost:: 00010001 00001100
00001110 0011001000010001 00001100 00001110 00110010 ANDing with
MaskANDing with Mask: /28 (28 1s): /28 (28 1s) 11111111 11111111
11111111 1111000011111111 11111111 11111111 11110000 We get the
subnetWe get the subnet:: 00010001 00001100 00001110
0011000000010001 00001100 00001110 00110000
17.12.14.4817.12.14.48
- 111. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 114114 More Levels of HierarchyMore Levels of Hierarchy
The structure of classless addressing does notThe structure of
classless addressing does not restrict the number of hierarchical
levels.restrict the number of hierarchical levels. An organization
can divide the granted block ofAn organization can divide the
granted block of addresses into subblocks.addresses into subblocks.
Each subblock can in turn be divided into smallerEach subblock can
in turn be divided into smaller subblocks. And so on.subblocks. And
so on. One example of this is seen in the ISPs.One example of this
is seen in the ISPs. A national ISP can divide a granted large
block into smallerA national ISP can divide a granted large block
into smaller blocks and assign each of them to a regional
ISP.blocks and assign each of them to a regional ISP. A regional
ISP can divide the block received from theA regional ISP can divide
the block received from the national ISP into smaller blocks and
assign each one to anational ISP into smaller blocks and assign
each one to a local ISP.local ISP. A local ISP can divide the block
received from the regionalA local ISP can divide the block received
from the regional ISP into smaller blocks and assign each one to a
differentISP into smaller blocks and assign each one to a different
organization.organization. Finally, an organization can divide the
received block andFinally, an organization can divide the received
block and make several subnets out of it.make several subnets out
of it.
- 112. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 115115 Address AllocationAddress Allocation The ultimate
responsibility of address allocationThe ultimate responsibility of
address allocation is given to a global authority called the
Internetis given to a global authority called the Internet
Corporation for Assigned Names and AddressesCorporation for
Assigned Names and Addresses (ICANN).(ICANN). However, ICANN does
not normally allocateHowever, ICANN does not normally allocate
addresses to individual organizations.addresses to individual
organizations. It assigns a large block of addresses to an ISP.It
assigns a large block of addresses to an ISP. Each ISP, in turn,
divides its assigned block intoEach ISP, in turn, divides its
assigned block into smaller subblocks and grants the subblocks
tosmaller subblocks and grants the subblocks to its customers.its
customers. In other words, an ISP receives one large block toIn
other words, an ISP receives one large block to be distributed to
its Internet users.be distributed to its Internet users. This is
calledThis is called address aggregationaddress aggregation: many
blocks: many blocks of addresses are aggregated in one block andof
addresses are aggregated in one block and granted to one
ISP.granted to one ISP.
- 113. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 116116 An ISP is granted a block of addresses startingAn
ISP is granted a block of addresses starting with 190.100.0.0/16
(65,536 addresses). The ISPwith 190.100.0.0/16 (65,536 addresses).
The ISP needs to distribute these addresses to threeneeds to
distribute these addresses to three groups of customers as
follows:groups of customers as follows: a.a. The first group hasThe
first group has 64 customers64 customers; each needs; each needs
256 addresses256 addresses.. b.b. The second group hasThe second
group has 128 customers128 customers; each; each needsneeds 128
addresses128 addresses.. c.c. The third group hasThe third group
has 128 customers128 customers; each needs; each needs 64
addresses64 addresses.. Design the sub blocks and find out how
manyDesign the sub blocks and find out how many addresses are still
available after theseaddresses are still available after these
allocations.allocations. Example 19.10Example 19.10
- 114. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 117117 Solution Figure 19.9 shows the situation. Group 1
For this group, each customer needs 256 addresses. This means that
8 (log2 256) bits are needed to define each host. The prefix length
is then 32 8 = 24. The addresses are Example 19.10 (contd.)Example
19.10 (contd.)
- 115. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 118118 Group 2 For this group, each customer needs 128
addresses. This means that 7 (log2 128) bits are needed to define
each host. The prefix length is then 32 7 = 25. The addresses are
Example 19.10 (contd.)Example 19.10 (contd.)
- 116. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 119119 Group 3 For this group, each customer needs 64
addresses. This means that 6 (log264) bits are needed to each host.
The prefix length is then 32 6 = 26. The addresses are Number of
granted addresses to the ISP: 65,536 Number of allocated addresses
by the ISP: 40,960 Number of available addresses: 24,576 Example
19.10 (contd.)Example 19.10 (contd.)
- 117. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 120120 Address allocation and distribution byAddress
allocation and distribution by an ISPan ISP
- 118. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 121121 Lecture 36Lecture 36 (26 Mar 2014)(26 Mar 2014) IP
v6IP v6
- 119. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 122122 IPv6IPv6 IPngIPng Next-Generation
IPNext-Generation IP
- 120. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 123123 Why A New IP?Why A New IP? Inefficient usage of
available IP addresses classfulInefficient usage of available IP
addresses classful schemescheme IP address depletion/exhaustionIP
address depletion/exhaustion Aug 90 - Class B exhausted by Mar
94Aug 90 - Class B exhausted by Mar 94 Backbone routing table
growthBackbone routing table growth Too much data to exchangeToo
much data to exchange Routing calculation complexityRouting
calculation complexity Other issuesOther issues Security - No
security mechanism (no encryption andSecurity - No security
mechanism (no encryption and authentication is provided by
IPv4).authentication is provided by IPv4). Quality of Service -
Inadequate QoS for nowadaysQuality of Service - Inadequate QoS for
nowadays application such as real-time audio and video
transmissionapplication such as real-time audio and video
transmission (due to delay & resource reservation) strategy(due
to delay & resource reservation) strategy
- 121. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 124124 ADVANTAGE OF IPv6ADVANTAGE OF IPv6 Larger address
spaceLarger address space: IPv4 only 2: IPv4 only 23232 . IPv6 2.
IPv6 2128128
340,282,366,920,938,463,463,374,607,431,768,211,340,282,366,920,938,463,463,374,607,431,768,211,
456 addresses. Can stand more than 150 years456 addresses. Can
stand more than 150 years BetterBetter header formatheader format
New optionsNew options: allow for additional functionalities: allow
for additional functionalities for future usefor future use
Allowance for extensionAllowance for extension: allow the extension
of: allow the extension of the protocol if required by new
technologies orthe protocol if required by new technologies or
applications.applications. Support for resource allocationSupport
for resource allocation.- to support.- to support traffic such as
real-time audio and video verytraffic such as real-time audio and
video very very efficiently compared to IPv4.very efficiently
compared to IPv4. Support for more securitySupport for more
security. The encryption and. The encryption and authentication
options in IPv6 provideauthentication options in IPv6 provide
confidentiality and integrity of the packet.confidentiality and
integrity of the packet.
- 122. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 126126 Features of IPv6Features of IPv6 Larger Address
SpaceLarger Address Space Efficient and hierarchical addressing and
routingEfficient and hierarchical addressing and routing
infrastructureinfrastructure efficient, hierarchical, and
summarizable routingefficient, hierarchical, and summarizable
routing infrastructureinfrastructure Aggregation-based address
hierarchy EfficientAggregation-based address hierarchy Efficient
backbone routing smaller routing tablesbackbone routing smaller
routing tables Efficient and Extensible IP datagramEfficient and
Extensible IP datagram Efficient Header FormatEfficient Header
Format The IPv6 header has a new format that is designed toThe IPv6
header has a new format that is designed to minimize header
overhead.minimize header overhead. This is achieved by moving both
nonessential fields andThis is achieved by moving both nonessential
fields and option fields to extension headers that are placed
afteroption fields to extension headers that are placed after the
IPv6 header.the IPv6 header. The streamlined IPv6 header provides
more efficientThe streamlined IPv6 header provides more efficient
processing at intermediate routers.processing at intermediate
routers.
- 123. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 127127 Features of IPv6Features of IPv6
Auto-configuration - To simplify host
configuration,Auto-configuration - To simplify host configuration,
Stateless and stateful address configurationStateless and stateful
address configuration stateful address configuration, such as
address configuration in thestateful address configuration, such as
address configuration in the presence of a DHCP server - hosts on a
link automatically configurepresence of a DHCP server - hosts on a
link automatically configure themselves with IPv6 addresses for the
link (link-local addresses)themselves with IPv6 addresses for the
link (link-local addresses) stateless address configuration
(address configuration in the absence ofstateless address
configuration (address configuration in the absence of a DHCP
server) - are derived from prefixes advertised by local routers.a
DHCP server) - are derived from prefixes advertised by local
routers. Even in the absence of a router, hosts on the same link
can automaticallyEven in the absence of a router, hosts on the same
link can automatically configure themselves with link-local
addresses and communicateconfigure themselves with link-local
addresses and communicate without manual configuration.without
manual configuration. Built-in security - IPsec mandatoryBuilt-in
security - IPsec mandatory Better support for quality of service
(QoS) - New fields in the IPv6Better support for quality of service
(QoS) - New fields in the IPv6 header define how traffic is handled
and identified - traffic isheader define how traffic is handled and
identified - traffic is identified in the IPv6 header, support for
QoS can be easily achievedidentified in the IPv6 header, support
for QoS can be easily achieved even when the packet payload is
encrypted with IPSeceven when the packet payload is encrypted with
IPSec New protocol for neighboring node interaction - The
NeighborNew protocol for neighboring node interaction - The
Neighbor Discovery protocol for IPv6 - Neighbor Discovery replaces
AddressDiscovery protocol for IPv6 - Neighbor Discovery replaces
Address Resolution Protocol (ARP)Resolution Protocol (ARP)
Extensibility - IPv6 can be extended for new features by
addingExtensibility - IPv6 can be extended for new features by
adding extension headers after the IPv6 header.extension headers
after the IPv6 header. MobilityMobility
- 124. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 128128 IPv6 Improvements over IPv4IPv6 Improvements over
IPv4 Longer addresses than IPv4Longer addresses than IPv4 16 Bytes
128 bits long16 Bytes 128 bits long Provides unlimited supply of
Internet AddressesProvides unlimited supply of Internet Addresses
Simplification of the headerSimplification of the header Contains 7
fields (13 in IPv4)Contains 7 fields (13 in IPv4) Allows routers to
process packets fasterAllows routers to process packets faster
Improves throughput and delayImproves throughput and delay Better
support for optionsBetter support for options Required because
fields previously required for IPv4 are nowRequired because fields
previously required for IPv4 are now optionaloptional Options are
represented in a different way makes simple forOptions are
represented in a different way makes simple for routers to skip
over options not intended for them this featurerouters to skip over
options not intended for them this feature speeds up packet
processing timespeeds up packet processing time Big advance in
securityBig advance in security Authentication and privacy are key
featuresAuthentication and privacy are key features More attention
to Quality of service (QoS)More attention to Quality of service
(QoS) AutoconfigurationAutoconfiguration
- 125. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 133133 IPv6 AddressesIPv6 Addresses 128-bit long. Fixed
size128-bit long. Fixed size Larger Address space - 2Larger Address
space - 2128128 = 3.410= 3.4103838 addressesaddresses
66510665102121 addresses per sq. m of earth surfaceaddresses per
sq. m of earth surface If assigned at the rate of 10If assigned at
the rate of 1066 //s, it would take 20s, it would take 20
yearsyears Expected to support 810Expected to support 8101717 to
210to 2103333 addressesaddresses 8108101717 1,564 address per sq.
m1,564 address per sq. m Allows multiple interfaces per host.Allows
multiple interfaces per host. Allows multiple addresses per
interfaceAllows multiple addresses per interface Allows unicast,
multicast, anycastAllows unicast, multicast, anycast Allows
provider based, site-local, link-localAllows provider based,
site-local, link-local 85% of the space is unassigned85% of the
space is unassigned
- 126. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 137137 IPv6 AddressingIPv6 Addressing 128 bit
addresses!128 bit addresses!
340,282,366,920,938,463,463,374,607,431340,282,366,920,938,463,463,374,607,431
,768,211,456 addresses!,768,211,456 addresses! Uses hierarchical
addressing structureUses hierarchical addressing structure Allows
embedding of IEEE 802 addressAllows embedding of IEEE 802 address
as EUI-64 identifiersas EUI-64 identifiers Specified as 8 16-bit
hexadecimalSpecified as 8 16-bit hexadecimal numbers separated by
colonsnumbers separated by colons
- 127. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 138138 Hexadecimal Colon NotationHexadecimal Colon
Notation Written asWritten as eight sectionseight sections each of
2 byte length separated by colonseach of 2 byte length separated by
colons 2 bytes (16 bits) in hexadecimal requires2 bytes (16 bits)
in hexadecimal requires four hexadecimal digitsfour hexadecimal
digits Therefore address contain 32 hexadecimal digits with every
four digits separated byTherefore address contain 32 hexadecimal
digits with every four digits separated by a colona colon So, There
are:So, There are: 8 groups of 4 hexadecimal digits.8 groups of 4
hexadecimal digits. Each group represents 16 bits (4 hexa digits X
4 bit)Each group represents 16 bits (4 hexa digits X 4 bit)
Separator is : (colon)Separator is : (colon) Hex digits are not
case sensitive, so DBCA is same as dbca or DBcaHex digits are not
case sensitive, so DBCA is same as dbca or DBca
- 128. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 139139 Abbreviated IPv6 AddressesAbbreviated IPv6
Addresses TheThe leading zeros within a group can be omittedleading
zeros within a group can be omitted only the leading zeros can be
only the leading zeros can be dropped, not the trailing
zerosdropped, not the trailing zeros Further abbreviations are
possible if there areFurther abbreviations are possible if there
are consecutive sectionsconsecutive sections consistingconsisting
of zeros only.of zeros only. One or more consecutive groups of
zeros can be replaced by a pair of colons One or more consecutive
groups of zeros can be replaced by a pair of colons allowed only
once per addressallowed only once per address Re-expansion of the
abbreviated address is very simple: Align the
unabbreviatedRe-expansion of the abbreviated address is very
simple: Align the unabbreviated portions and insert zeros to get
the original expanded address.portions and insert zeros to get the
original expanded address.
- 129. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 140140 Expand the address 0:15::1:12:1213 to its
original. Solution We first need to align the left side of the
double colon to the left of the original pattern and the right side
of the double colon to the right of the original pattern to find
how many 0s we need to replace the double colon. This means that
the original address is. Example 19.11Example 19.11
- 130. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 141141 Prefix and Interface IDPrefix and Interface ID
IPv6 (128-bit) address contains two parts:IPv6 (128-bit) address
contains two parts: The first 64-bits is known as theThe first
64-bits is known as the prefixprefix. The prefix. The prefix
includes the network and subnet address. Becauseincludes the
network and subnet address. Because addresses are allocated based
on physical location, theaddresses are allocated based on physical
location, the prefix also includes global routing information. The
64-prefix also includes global routing information. The 64- bit
prefix is often referred to as the global routingbit prefix is
often referred to as the global routing prefix.prefix. The last
64-bits is theThe last 64-bits is the interface IDinterface ID.
This is the unique. This is the unique address assigned to an
interface.address assigned to an interface. NoteNote: Addresses are
assigned to interfaces (network: Addresses are assigned to
interfaces (network connections), not to the host. Each interface
can haveconnections), not to the host. Each interface can have more
than one IPv6 address.more than one IPv6 address.
- 131. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 142142 IPv6 Addressing In UseIPv6 Addressing In Use IPv6
uses theIPv6 uses the / notation/ notation to denote howto denote
how many bits in the IPv6 address representmany bits in the IPv6
address represent the subnet.the subnet. The full syntax of IPv6
isThe full syntax of IPv6 is
ipv6-address/prefix-lengthipv6-address/prefix-length wherewhere
ipv6-address is the 128-bit IPv6 addressipv6-address is the 128-bit
IPv6 address /prefix-length is a decimal value/prefix-length is a
decimal value representing how many of the left mostrepresenting
how many of the left most contiguous bits of the address
comprisecontiguous bits of the address comprise the prefix.the
prefix.
- 132. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 143143 IPv6 Addressing In UseIPv6 Addressing In Use Lets
analyze an example:Lets analyze an example:
2001:C:7:ABCD::1/642001:C:7:ABCD::1/64 is reallyis really
2001:000C:0007:ABCD2001:000C:0007:ABCD::0000:0000:0000:00010000:0000:0000:0001//6464
The first 64-bitsThe first 64-bits
2001:000C:0007:ABCD2001:000C:0007:ABCD is theis the address
prefixaddress prefix The last 64-bitsThe last 64-bits
0000:0000:0000:00010000:0000:0000:0001 is theis the interface
IDinterface ID /64/64 is theis the prefix lengthprefix length (/64
is well-known and(/64 is well-known and also the prefix length in
most cases)also the prefix length in most cases)
- 133. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 144144 Address SpaceAddress Space IPv6 is divided
intoIPv6 is divided into several categoriesseveral categories.. A
few leftmost bits, called theA few leftmost bits, called the
typetype prefixprefix, in each address define its, in each address
define its category.category. The type prefix isThe type prefix is
variable in lengthvariable in length
- 134. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 145145 Type Prefixes for IPv6Type Prefixes for IPv6
AddressesAddresses
- 135. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 146146 Type Prefixes for IPv6Type Prefixes for IPv6
AddressesAddresses
- 136. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 147147 IPv6IPv6 IPv6 supports 3 types of addressesIPv6
supports 3 types of addresses UnicastUnicast MulticastMulticast
AnycastAnycast
- 137. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 148148 IPv6 Address TypesIPv6 Address Types A single
interface may be assigned multiple IPv6 addresses of any type
(unicast, anycast, multicast) Address TypeAddress Type
DescriptionDescription UnicastUnicast One to One (Global, Link
local, Site local) + An address destined for a single interface.
MulticastMulticast One to Many + An address for a set of interfaces
+ Delivered to a group of interfaces identified by that address. +
Replaces IPv4 broadcast AnycastAnycast One to Nearest (Allocated
from Unicast) + Delivered to the closest interface as determined by
the IGP
- 138. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 149149 Lecture 37Lecture 37 (27 Mar 2014)(27 Mar 2014) IP
v6 contdIP v6 contd ..
- 139. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 150150 Unicast AddressesUnicast Addresses Unicast
addresses identify a singleUnicast addresses identify a single
interface, so defines a single computer.interface, so defines a
single computer. The packet sent to a unicast address mustThe
packet sent to a unicast address must be delivered to that specific
computer.be delivered to that specific computer. IPv6 defines two
types of unicastIPv6 defines two types of unicast
addresses:addresses: Geographically based, andGeographically based,
and provider-based - the provider-based address isprovider-based -
the provider-based address is generally used by a normal host as a
unicastgenerally used by a normal host as a unicast
address.address.
- 140. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 151151 Multicast AddressesMulticast Addresses Multicast
addresses identify a group ofMulticast addresses identify a group
of interfaces - which define a group of hostsinterfaces - which
define a group of hosts instead of just one.instead of just one. A
packet sent to a multicast address isA packet sent to a multicast
address is delivered to all of the interfaces in thedelivered to
all of the interfaces in the group in turn delivered to each
membergroup in turn delivered to each member of the group.of the
group. NOTE: There are no broadcast addresses inNOTE: There are no
broadcast addresses in IPv6, their function being superseded
byIPv6, their function being superseded by multicast
addresses.multicast addresses.
- 141. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 152152 Anycast AddressesAnycast Addresses IPv6 also
defines anycast addresses.IPv6 also defines anycast addresses.
Anycast addresses identify a set of interfaces such that aAnycast
addresses identify a set of interfaces such that a packet sent to a
anycast address will be delivered to onepacket sent to a anycast
address will be delivered to one member of the set.member of the
set. An anycast address, like a multicast address, alsoAn anycast
address, like a multicast address, also defines adefines a group of
nodesgroup of nodes.. However, a packet destined for an anycast
address isHowever, a packet destined for an anycast address is
delivered to only one of the members of the anycast group,delivered
to only one of the members of the anycast group, thethe nearest
onenearest one (the one with the shortest route).(the one with the
shortest route). Although the definition of an anycast address is
stillAlthough the definition of an anycast address is still
debatable, one possible use is to assign an anycastdebatable, one
possible use is to assign an anycast address to all routers of an
ISP that covers a large logicaladdress to all routers of an ISP
that covers a large logical area in the Internet.area in the
Internet. The routers outside the ISP deliver a packet destined
forThe routers outside the ISP deliver a packet destined for the
ISP to the nearest ISP router.the ISP to the nearest ISP router. No
block is assigned for anycast addresses.No block is assigned for
anycast addresses.
- 142. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 153153 Reserved AddressesReserved Addresses Another
category in the addressAnother category in the address space is the
reserved address.space is the reserved address. These addresses
start with eight OsThese addresses start with eight Os (type prefix
is 00000000).(type prefix is 00000000). A few subcategories are
furtherA few subcategories are further defined in this
categorydefined in this category
- 143. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 154154 Reserved Addresses in IPv6Reserved Addresses in
IPv6
- 144. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 155155 Local AddressesLocal Addresses These addresses are
used when anThese addresses are used when an organization wants to
use IPv6 protocolorganization wants to use IPv6 protocol without
being connected to the globalwithout being connected to the global
Internet.Internet. In other words, they provide addressingIn other
words, they provide addressing for private networks.for private
networks. Nobody outside the organization can sendNobody outside
the organization can send a message to the nodes using thesea
message to the nodes using these addresses.addresses. Two types of
addresses are defined forTwo types of addresses are defined for
this purposethis purpose Link LocalLink Local Site LocalSite
Local
- 145. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 156156 SecuritySecurity IPv6 adds three security
servicesIPv6 adds three security services Packet
authenticationPacket authentication Packet integrityPacket
integrity Packet confidentialityPacket confidentiality Implemented
using theImplemented using the Authentication Header and
theAuthentication Header and the Encapsulating Security
PayloadEncapsulating Security Payload HeaderHeader
- 146. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 157157 IPv6 HeadersIPv6 Headers Simpler header - faster
processingSimpler header - faster processing by routers.by routers.
No optional fields - fixed size (40 bytes)No optional fields -
fixed size (40 bytes) No fragmentation fields.No fragmentation
fields. No checksumNo checksum Support for multiple headersSupport
for multiple headers more flexible than simple protocolmore
flexible than simple protocol field.field.
- 147. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 158158 IPv4 HeaderIPv4 Header VERS HL Fragment Offset
Fragment LengthService Datagram ID FLAG TTL Protocol Header
Checksum Source Address Destination Address Options (if any) Data 1
byte1 byte 1 byte 1 byte
- 148. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 159159 IPv6 HeaderIPv6 Header VERS PRIO Hop Limit Flow
Label Payload Length Next Header 1 byte1 byte 1 byte 1 byte Source
Address (128 bits - 16 bytes) Dest. Address (128 bits - 16
bytes)
- 149. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 160160 IPv6 Header FieldsIPv6 Header Fields VERS:VERS: IP
version number 6 (4 for IPv4)IP version number 6 (4 for IPv4)
Priority/Traffic Class:Priority/Traffic Class: will be used in
congestionwill be used in congestion control to distinguish between
packet withcontrol to distinguish between packet with different
real-time delivery requirementsdifferent real-time delivery
requirements Flow Label:Flow Label: experimental - sender can label
aexperimental - sender can label a sequence of packets as being in
the same flow.sequence of packets as being in the same flow.
Payload LengthPayload Length: number of bytes following the 40:
number of bytes following the 40 byte headerbyte header Next
Header:Next Header: tells which of the six extensiontells which of
the six extension headers follow this oneheaders follow this one
Hop Limit:Hop Limit: same as TTL field in IPv4same as TTL field in
IPv4 Source/Destination Address:Source/Destination Address: 16
Bytes each16 Bytes each
- 150. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 161161 Extension HeadersExtension Headers
- 151. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 162162 Extension HeadersExtension Headers Hop-by-Hop
Option Special options thatHop-by-Hop Option Special options that
require hop-by-hop processingrequire hop-by-hop processing
Destination Options Optional information toDestination Options
Optional information to be examined by the destination nodebe
examined by the destination node Routing Extended routing, like
IPv4 loose listRouting Extended routing, like IPv4 loose list of
routers to visitof routers to visit Fragmentation Fragmentation
andFragmentation Fragmentation and reassemblyreassembly
Authentication Integrity and authentication,Authentication
Integrity and authentication, securitysecurity Encrypted Security
payload ConfidentialityEncrypted Security payload
Confidentiality
- 152. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 163163 IPv6 Vs IPv4 HeaderIPv6 Vs IPv4 Header IPv6 twice
the size of IPv4 headerIPv6 twice the size of IPv4 header Version:
only field with same position andVersion: only field with same
position and meaningmeaning RemovedRemoved:: Header length,
fragmentation fieldsHeader length, fragmentation fields
(identification, flags, fragment offset),(identification, flags,
fragment offset), header checksumheader checksum ReplacedReplaced::
Datagram length by payload lengthDatagram length by payload length
Protocol type by next headerProtocol type by next header Time to
live by hop limitTime to live by hop limit Type of service by class
octetType of service by class octet
- 153. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 164164 Major Improvements of IPv6Major Improvements of
IPv6 HeaderHeader No option fieldNo option field: Replaced by:
Replaced by extension header. Result in a fixedextension header.
Result in a fixed length, 40-byte IP header.length, 40-byte IP
header. No header checksumNo header checksum: Result in fast:
Result in fast processing.processing. No fragmentation at
intermediateNo fragmentation at intermediate nodesnodes: Result in
fast IP forwarding.: Result in fast IP forwarding.
- 154. May 20, 2015May 20, 2015 BMK, AKGEC, GhaziabadBMK, AKGEC,
Ghaziabad 165165 4040 bytesbytes 6060 bytesbytes IPv4IPv4 IPv6IPv6
00 1515 1616 3131 vers IHL TOS total lengthvers IHL TOS total
length identification flags frag-offsetidentification flags
frag-offset TTL protocol header checksumTTL protocol header
checksum source addresssource address destination
addressdestination address options and paddingoption