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

TCP/IP Protocol Suite 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

TCP/IP Protocol Suite 3 Figure 27.1 IPv6 address

TCP/IP Protocol Suite 4 Figure 27.2 Abbreviated address

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

TCP/IP Protocol Suite 6 Figure 27.4 CIDR address

TCP/IP Protocol Suite 7 Figure 27.5 Address structure

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

9 Table 27.1 Type prefixes for IPv6 addresses

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

TCP/IP Protocol Suite 11 Figure 27.7 Address hierarchy

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

TCP/IP Protocol Suite 13 Figure 27.8 Unspecified address

TCP/IP Protocol Suite 14

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

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

TCP/IP Protocol Suite 17 Figure 27.9 Loopback address

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

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

TCP/IP Protocol Suite 20 Figure Compatible address

TCP/IP Protocol Suite 21 Figure Mapped address

TCP/IP Protocol Suite 22 Figure Link local address

TCP/IP Protocol Suite 23 Figure Site local address

TCP/IP Protocol Suite 24 Figure Multicast address

TCP/IP Protocol Suite 25 Figure IPv6 datagram

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

TCP/IP Protocol Suite 27 Table 27.2 Next header codes

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

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

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

TCP/IP Protocol Suite 31 Figure Extension header format

TCP/IP Protocol Suite 32 Figure Extension header types

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

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

TCP/IP Protocol Suite 35 Figure Pad1

TCP/IP Protocol Suite 36 Figure PadN

TCP/IP Protocol Suite 37 Figure Jumbo payload

TCP/IP Protocol Suite 38 Figure Source routing

TCP/IP Protocol Suite 39 Figure Source routing example

TCP/IP Protocol Suite 40 Figure Fragmentation

TCP/IP Protocol Suite 41 Figure Authentication

TCP/IP Protocol Suite 42 Figure Calculation of authentication data

TCP/IP Protocol Suite 43 Figure Encrypted security payload

TCP/IP Protocol Suite 44 Figure Transport mode encryption

TCP/IP Protocol Suite 45 Figure Tunnel-mode encryption

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

TCP/IP Protocol Suite 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

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

TCP/IP Protocol Suite 49 Figure Categories of ICMPv6 messages

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

TCP/IP Protocol Suite 51 Figure Error-reporting messages

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

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

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

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

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

TCP/IP Protocol Suite 57 Figure Redirection message format

TCP/IP Protocol Suite 58 Figure Query messages

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

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

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

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

TCP/IP Protocol Suite 63 Figure Group-membership messages

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

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

TCP/IP Protocol Suite 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

TCP/IP Protocol Suite 67 Figure Three transition strategies

TCP/IP Protocol Suite 68 Figure Dual stack

TCP/IP Protocol Suite 69 Figure Automatic tunneling

TCP/IP Protocol Suite 70 Figure Configured tunneling

TCP/IP Protocol Suite 71 Figure Header translation

TCP/IP Protocol Suite 72 Table 27.9 Header translation