1. TCP/IP Protocol Suite 1 Chapter 27 Upon completion you will be able to: Next Generation: IPv6 and ICMPv6 Understand the shortcomings of IPv4 Know the IPv6 address format, address types, and abbreviations Be familiar with the IPv6 header format Know the extension header types Know the differences between ICMPv4 and ICMPv6 Know the strategies for transitioning from IPv4 to IPv6 Objectives

2. TCP/IP Protocol Suite 2 27.1 IPv6 IPv6 has these advantages over IPv4: 1. larger address space 2. better header format 3. new options 4. allowance for extension 5. support for resource allocation 6. support for more security The topics discussed in this section include: IPv6 Addresses Address Space Assignment Packet Format Comparison between IPv4 and IPv6

3. TCP/IP Protocol Suite 3 Figure 27.1 IPv6 address

4. TCP/IP Protocol Suite 4 Figure 27.2 Abbreviated address

5. TCP/IP Protocol Suite 5 Figure 27.3 Abbreviated address with consecutive zeros

6. TCP/IP Protocol Suite 6 Figure 27.4 CIDR address

7. TCP/IP Protocol Suite 7 Figure 27.5 Address structure

8. The below table shows the prefix for each type of address. TCP/IP Protocol Suite 8

9. 9 Table 27.1 Type prefixes for IPv6 addresses

10. TCP/IP Protocol Suite 10 Figure 27.6 Provider-based address

11. TCP/IP Protocol Suite 11 Figure 27.7 Address hierarchy

12. Unspecified address It is a sub block containing only one single address,which is defined by letting all suffix bits to zeros. It is used during bootstrap when a host does not know its own address and wants to send an inquiry to find it. It should never be used as destination address. The CIDR notation for this is ::/128 TCP/IP Protocol Suite 12

13. TCP/IP Protocol Suite 13 Figure 27.8 Unspecified address

14. TCP/IP Protocol Suite 14

15. Loopback address It also consists of one single address. It is used by an host to test itself without going into network. In this case message is created in the application layer,sent to the transport layer and passed to network layer. However,instead of going to the physical network it returns to the transport layer then passes to application layer. TCP/IP Protocol Suite 15

16. It is useful for testing the functions of software packages in these layers before even connecting the computer to the network. It is denoted as ::1/128 TCP/IP Protocol Suite 16

17. TCP/IP Protocol Suite 17 Figure 27.9 Loopback address

18. Embedded IPv4 addresses During the transition from IPv4 to IPv6,hosts can use their IPv4 addresses embedded inIPv6. There are two formats: Compatible address Mapped address TCP/IP Protocol Suite 18

19. Compatible address It is used when computer using IPv6 wants to send a message to a computer using IPv6. However,suppose the packet passes through TCP/IP Protocol Suite 19

20. TCP/IP Protocol Suite 20 Figure 27.10 Compatible address

21. TCP/IP Protocol Suite 21 Figure 27.11 Mapped address

22. TCP/IP Protocol Suite 22 Figure 27.12 Link local address

23. TCP/IP Protocol Suite 23 Figure 27.13 Site local address

24. TCP/IP Protocol Suite 24 Figure 27.14 Multicast address

25. TCP/IP Protocol Suite 25 Figure 27.15 IPv6 datagram

26. TCP/IP Protocol Suite 26 Figure 27.16 Format of an IPv6 datagram

27. TCP/IP Protocol Suite 27 Table 27.2 Next header codes

28. TCP/IP Protocol Suite 28 Table 27.3 Priorities for congestion-controlled traffic

29. TCP/IP Protocol Suite 29 Table 27.4 Priorities for noncongestion-controlled traffic

30. TCP/IP Protocol Suite 30 Table 27.5 Comparison between IPv4 and IPv6 packet header

31. TCP/IP Protocol Suite 31 Figure 27.17 Extension header format

32. TCP/IP Protocol Suite 32 Figure 27.18 Extension header types

33. TCP/IP Protocol Suite 33 Figure 27.19 Hop-by-hop option header format

34. TCP/IP Protocol Suite 34 Figure 27.20 The format of options in a hop-by-hop option header

35. TCP/IP Protocol Suite 35 Figure 27.21 Pad1

36. TCP/IP Protocol Suite 36 Figure 27.22 PadN

37. TCP/IP Protocol Suite 37 Figure 27.23 Jumbo payload

38. TCP/IP Protocol Suite 38 Figure 27.24 Source routing

39. TCP/IP Protocol Suite 39 Figure 27.25 Source routing example

40. TCP/IP Protocol Suite 40 Figure 27.26 Fragmentation

41. TCP/IP Protocol Suite 41 Figure 27.27 Authentication

42. TCP/IP Protocol Suite 42 Figure 27.28 Calculation of authentication data

43. TCP/IP Protocol Suite 43 Figure 27.29 Encrypted security payload

44. TCP/IP Protocol Suite 44 Figure 27.30 Transport mode encryption

45. TCP/IP Protocol Suite 45 Figure 27.31 Tunnel-mode encryption

46. TCP/IP Protocol Suite 46 Table 27.6 Comparison between IPv4 options and IPv6 extension headers

47. TCP/IP Protocol Suite 47 27.2 ICMPv6 ICMPv6, while similar in strategy to ICMPv4, has changes that makes it more suitable for IPv6. ICMPv6 has absorbed some protocols that were independent in version 4. The topics discussed in this section include: Error Reporting Query

48. TCP/IP Protocol Suite 48 Figure 27.32 Comparison of network layers in version 4 and version 6

49. TCP/IP Protocol Suite 49 Figure 27.33 Categories of ICMPv6 messages

50. TCP/IP Protocol Suite 50 Figure 27.34 General format of ICMP messages

51. TCP/IP Protocol Suite 51 Figure 27.35 Error-reporting messages

52. TCP/IP Protocol Suite 52 Table 27.7 Comparison of error-reporting messages in ICMPv4 and ICMPv6

53. TCP/IP Protocol Suite 53 Figure 27.36 Destination-unreachable message format

54. TCP/IP Protocol Suite 54 Figure 27.37 Packet-too-big message format

55. TCP/IP Protocol Suite 55 Figure 27.38 Time-exceeded message format

56. TCP/IP Protocol Suite 56 Figure 27.39 Parameter-problem message format

57. TCP/IP Protocol Suite 57 Figure 27.40 Redirection message format

58. TCP/IP Protocol Suite 58 Figure 27.41 Query messages

59. TCP/IP Protocol Suite 59 Table 27.8 Comparison of query messages in ICMPv4 and ICMPv6

60. TCP/IP Protocol Suite 60 Figure 27.42 Echo request and reply messages

61. TCP/IP Protocol Suite 61 Figure 27.43 Router-solicitation and advertisement message formats

62. TCP/IP Protocol Suite 62 Figure 27.44 Neighbor-solicitation and advertisement message formats

63. TCP/IP Protocol Suite 63 Figure 27.45 Group-membership messages

64. TCP/IP Protocol Suite 64 Figure 27.46 Group-membership message formats

65. TCP/IP Protocol Suite 65 Figure 27.47 Four situations of group-membership operation

66. TCP/IP Protocol Suite 66 27.3 TRANSITION FROM IPv4 TO IPv6 Three strategies have been devised by the IETF to provide for a smooth transition from IPv4 to IPv6. The topics discussed in this section include: Dual Stack Tunneling Header Translation

67. TCP/IP Protocol Suite 67 Figure 27.48 Three transition strategies

68. TCP/IP Protocol Suite 68 Figure 27.49 Dual stack

69. TCP/IP Protocol Suite 69 Figure 27.50 Automatic tunneling

70. TCP/IP Protocol Suite 70 Figure 27.51 Configured tunneling

71. TCP/IP Protocol Suite 71 Figure 27.52 Header translation

72. TCP/IP Protocol Suite 72 Table 27.9 Header translation