Understanding IPv6 Slide: 1 Lesson 11 Coexistence and Migration

Understanding IPv6 Slide: 1

Lesson 11

Coexistence and Migration


Lesson Objectives

Coexistence and migration overview Coexistence mechanisms Tunneling configurations 6over4 6to4 ISATAP PortProxy Migrating to IPv6


Coexistence and Migration Overview

The transition from IPv4 to IPv6 will take years Some hosts will use IPv4 indefinitely Migration is the long term goal, coexistence in the interim

Transition criteria: Existing IPv4 hosts can be upgraded at any time

independent of the upgrade of other hosts or routers New hosts using only IPv6 can be added at any time

without dependencies on other hosts or routing infrastructure

Existing IPv4 hosts with IPv6 installed can continue to use their IPv4 address and do not need additional addresses

Little preparation is needed to upgrade existing IPv4 nodes to IPv6 or to deploy new IPv6 nodes


Node Types

IPv4-only node IPv6-only node IPv6/IPv4 node IPv4 node IPv6 node


Compatibility Addresses

IPv4-compatible addresses ::w.x.y.z

IPv4-mapped addresses ::FFFF:w.x.y.z

6over4 addresses Interface ID of ::WWXX:YYZZ

6to4 addresses Prefix of 2002:WWXX:YYZZ::/48

ISATAP addresses Interface ID of ::0:5EFE:w.x.y.z


Coexistence Mechanisms

Dual IP layer IPv6 over IPv4 tunneling DNS infrastructure


ApplicationLayer

Transport Layer (TCP/UDP)

IPv6

Network Interface Layer

IPv4

Dual IP Layer Architecture


ApplicationLayer

TCP/UDP

IPv6

Network Interface Layer

TCP/UDP

IPv4

Dual Stack Architecture


IPv6 HeaderExtensionHeaders

Upper Layer Protocol Data Unit

IPv6 HeaderExtensionHeaders

Upper Layer Protocol Data Unit

IPv4 Header

IPv6 Packet

IPv4 Packet

IPv6 over IPv4 Tunneling


DNS Infrastructure

Address records A records for IPv4 nodes AAAA records for IPv6 nodes

Pointer records PTR records in IN-ADDR.ARPA domain for IPv4

nodes PTR records in IP6.INT domain for IPv6 nodes

Address selection rules Choosing the “best” set of addresses with

which to communicate


Tunneling Configurations

Router-to-Router Host-to-Router and Router-to-Host Host-to-Host


IPv4 or IPv6 Infrastructure

IPv4 Infrastructure

IPv6 over IPv4 Tunnel

IPv6/IPv4 Router IPv6/IPv4 Router

IPv6Node

IPv6Node

IPv4 or IPv6 Infrastructure

Router-to-Router Tunneling


IPv4 Infrastructure

IPv6/IPv4 IPv6

IPv6/IPv4 Router


Node A Node BIPv4 or IPv6 Infrastructure

Host-to-Router and Router-to-Host Tunneling


Host-to-Host Tunneling

IPv4 Infrastructure

IPv6/IPv4Node

IPv6/IPv4Node



Types of Tunnels

Configured Manual configuration of tunnel endpoints

Automatic Tunnel endpoints determined from use of logical

tunnel interfaces, routes, and source and destination IPv6 addresses

IPv6 Automatic Tunneling Uses IPv4-compatible addresses


6over4 Overview

Host-to-host, host-to-router, and router-to-host automatic tunneling technology

6over4 address: [64-bit prefix]::WWXX:YYZZ Link-local 6over4 address FE80::WWXX:YYZZ

6over4 treats an IPv4 multicast-enabled infrastructure as a single multicast-capable link

Used for unicast and multicast IPv6 traffic over an IPv4 infrastructure


IPv4 Multicast-Enabled Infrastructure

IPv6 Infrastructure

Host B

6over4Host IPv6/IPv4

Router

LogicalEquivalent

IPv6 Infrastructure

IPv6/IPv4Router

6over4Host

Host A

Host A

Host B


6over4


TypeLength

Address= 1

Zero IPv4 Address

Source and Target Link-Layer Address Options for 6over4


6to4 Overview

Address assignment and router-to-router automatic tunneling technology

6to4 address: 2002:WWXX:YYZZ:[SLA ID]:[Interface ID]

6to4 treats the IPv4 Internet as a single link

Used for unicast traffic over the IPv4 Internet


6to4 Relay RouterIPv6/IPv4

6to4 RouterIPv6/IPv4

IPv6Internet

6to4 Host AIPv6/IPv4

6to4 Host CIPv6/IPv4


Internet

6to4 Host BIPv6/IPv4

Site 2

IPv6 Host DIPv6-only

Site 1

6to4 Components


6to4 Support in Windows

With public IPv4 address, automatic configuration as a 6to4 host/router Able to communicate with other 6to4 sites Able to communicate with IPv6 Internet

With ICS, automatic configuration as a 6to4 router Enables forwarding Sends routing advertisements with 6to4 prefixes

SLA ID = Interface index of intranet interface


6to4 Relay RouterIPv6/IPv4


IPv6Internet

6to4 Host AIPv6/IPv4

6to4 Host CIPv6/IPv4


Internet

6to4 Host BIPv6/IPv4

Site 2

IPv6 Host DIPv6-only

6to4 Host/Router EIPv6/IPv4

Site 3

Site 1

6to4 for Windows


ISATAP Overview

Address assignment and host-to-host, host-to-router, and router-to-host automatic tunneling technology

ISATAP addresses: [64-bit prefix]:0:5EFE:w.x.y.z

ISATAP treats an IPv4 infrastructure as a single link

Used for unicast traffic across an IPv4 intranet


ISATAP Host BFE80::5EFE:192.168.41.30

ISATAP Host AFE80::5EFE:10.40.1.29

IPv4Infrastructure

Link-Local ISATAP Configuration


IPv4Infrastructure

ISATAP Host B3FFE:2900:D005:7:5EFE:192.168.41.30

ISATAP Router Configuration

ISATAP router Responds to tunneled router solicitations from

ISATAP hosts Forward traffic between ISATAP hosts and other

IPv6 subnets

ISATAPRouter

IPv6network

Example prefix: 3FFE:2900:D005:7::/64



131.107.0.1

Internet

ISATAP Host B2002:836B:1:2:0:5EFE:192.168.141.30

157.54.0.1

IPv4 Infrastructure

ISATAP Host A2002:9D36:1:2:0:5EFE:192.168.12.9

Part 3

Part 2

Part 1

6to4 Router AIPv6/IPv4

192.168.204.1

6to4 Router BIPv6/IPv4

192.168.39.1

IPv4 Infrastructure

192.168.12.9

192.168.141.30

Site A

Site B

ISATAP and 6to4 Example


PortProxy Service

TCP proxy for: IPv4 to IPv4 IPv4 to IPv6

IPv4-only host can communicate with IPv6-only server or application

IPv6 to IPv6 IPv6 to IPv4

IPv4-only host can communicate with IPv6-only server or application

Use to “IPv6-enable” IPv4-only applications running on a Windows .NET Server computer


PortProxy Coexistence Scenarios

An IPv4-only node can access an IPv6-only node

An IPv6-only node can access an IPv4-only node

An IPv6 node can access an IPv4-only service running on an IPv6/IPv4 node


Migrating to IPv6

1. Upgrade your applications to be independent of IPv4 or IPv6

2. Update the DNS infrastructure to support IPv6 addresses and PTR records

3. Upgrade hosts to IPv4/IPv6 nodes

4. Upgrade routing infrastructure for native IPv6 routing

5. Convert IPv4/IPv6 nodes to IPv6-only nodes


Review

Coexistence and migration overview Coexistence mechanisms Tunneling configurations 6over4 6to4 ISATAP PortProxy Migrating to IPv6

Documents

Understanding IPv6 Slide: 1 Lesson 11 Coexistence and Migration