Download Understanding IPv6

Lesson 11
Coexistence and Migration
Understanding IPv6
Slide: 1
Lesson Objectives
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Coexistence and migration overview
Coexistence mechanisms
Tunneling configurations
6over4
6to4
ISATAP
PortProxy
Migrating to IPv6
Understanding IPv6
Slide: 2
Coexistence and Migration Overview
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The transition from IPv4 to IPv6 will take
years
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Some hosts will use IPv4 indefinitely
Migration is the long term goal, coexistence in the interim
Transition criteria:
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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
Understanding IPv6
Slide: 3
Node Types
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IPv4-only node
IPv6-only node
IPv6/IPv4 node
IPv4 node
IPv6 node
Understanding IPv6
Slide: 4
Compatibility Addresses
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IPv4-compatible addresses
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IPv4-mapped addresses
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Interface ID of ::WWXX:YYZZ
6to4 addresses
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::FFFF:w.x.y.z
6over4 addresses
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::w.x.y.z
Prefix of 2002:WWXX:YYZZ::/48
ISATAP addresses
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Interface ID of ::0:5EFE:w.x.y.z
Understanding IPv6
Slide: 5
Coexistence Mechanisms
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Dual IP layer
IPv6 over IPv4 tunneling
DNS infrastructure
Understanding IPv6
Slide: 6
Dual IP Layer Architecture
Application
Layer
Transport Layer (TCP/UDP)
IPv6
IPv4
Network
Interface Layer
Understanding IPv6
Slide: 7
Dual Stack Architecture
Application
Layer
TCP/UDP
TCP/UDP
IPv6
IPv4
Network
Interface Layer
Understanding IPv6
Slide: 8
IPv6 over IPv4 Tunneling
IPv6 Packet
IPv4 Header
IPv6 Header
Extension
Headers
Upper Layer Protocol
Data Unit
IPv6 Header
Extension
Headers
Upper Layer Protocol
Data Unit
IPv4 Packet
Understanding IPv6
Slide: 9
DNS Infrastructure
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Address records
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Pointer records
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A records for IPv4 nodes
AAAA records for IPv6 nodes
PTR records in IN-ADDR.ARPA domain for IPv4
nodes
PTR records in IP6.INT domain for IPv6 nodes
Address selection rules
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Choosing the “best” set of addresses with which
to communicate
Understanding IPv6
Slide: 10
Tunneling Configurations
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Router-to-Router
Host-to-Router and Router-to-Host
Host-to-Host
Understanding IPv6
Slide: 11
Router-to-Router Tunneling
IPv4 or IPv6
Infrastructure
IPv4 Infrastructure
IPv4 or IPv6
Infrastructure
IPv6 over IPv4 Tunnel
IPv6
Node
IPv6
Node
IPv6/IPv4 Router
IPv6/IPv4 Router
Understanding IPv6
Slide: 12
Host-to-Router and Router-to-Host Tunneling
IPv4 Infrastructure
IPv4 or IPv6
Infrastructure
Node A
Node B
IPv6 over IPv4 Tunnel
IPv6/IPv4
IPv6
IPv6/IPv4 Router
Understanding IPv6
Slide: 13
Host-to-Host Tunneling
IPv4 Infrastructure
IPv6 over IPv4 Tunnel
IPv6/IPv4
Node
IPv6/IPv4
Node
Understanding IPv6
Slide: 14
Types of Tunnels
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Configured
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Automatic
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Manual configuration of tunnel endpoints
Tunnel endpoints determined from use of logical
tunnel interfaces, routes, and source and
destination IPv6 addresses
IPv6 Automatic Tunneling
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Uses IPv4-compatible addresses
Understanding IPv6
Slide: 15
6over4 Overview
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Host-to-host, host-to-router, and
router-to-host automatic tunneling
technology
6over4 address:
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[64-bit prefix]::WWXX:YYZZ
Link-local 6over4 address FE80::WWXX:YYZZ
6over4 treats an IPv4 multicastenabled infrastructure as a single
multicast-capable link
Used for unicast and multicast IPv6
traffic over an IPv4 infrastructure
Understanding IPv6
Slide: 16
6over4
IPv4 Multicast-Enabled
Infrastructure
Host A
Host B
6over4
Host
6over4
Host
IPv6 Infrastructure
IPv6/IPv4
Router
Logical
Equivalent
Host B
IPv6 Infrastructure
Host A
IPv6/IPv4
Router
Understanding IPv6
Slide: 17
Source and Target Link-Layer Address Options for 6over4
Type
Length
Address
=1
Zero
Understanding IPv6
IPv4 Address
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6to4 Overview
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Address assignment and router-torouter automatic tunneling technology
6to4 address:
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2002:WWXX:YYZZ:[SLA ID]:[Interface ID]
6to4 treats the IPv4 Internet as a single
link
Used for unicast traffic over the IPv4
Internet
Understanding IPv6
Slide: 19
6to4 Components
6to4 Relay Router
IPv6/IPv4
IPv6
Internet
IPv6 Host D
IPv6-only
6to4 Host C
IPv6/IPv4
Internet
Site 2
6to4 Router
IPv6/IPv4
6to4 Router
IPv6/IPv4
6to4 Host A
IPv6/IPv4
6to4 Host B
IPv6/IPv4
Site 1
Understanding IPv6
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6to4 Support in Windows
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With public IPv4 address, automatic
configuration as a 6to4 host/router
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Able to communicate with other 6to4 sites
Able to communicate with IPv6 Internet
With ICS, automatic configuration as a
6to4 router
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Enables forwarding
Sends routing advertisements with 6to4 prefixes
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SLA ID = Interface index of intranet interface
Understanding IPv6
Slide: 21
6to4 for Windows
6to4 Relay Router
IPv6/IPv4
IPv6
Internet
IPv6 Host D
IPv6-only
6to4 Host C
IPv6/IPv4
Internet
Site 3
Site 2
6to4 Router
6to4 Host/Router E
IPv6/IPv4
IPv6/IPv4
6to4 Router
IPv6/IPv4
6to4 Host A
IPv6/IPv4
6to4 Host B
IPv6/IPv4
Site 1
Understanding IPv6
Slide: 22
ISATAP Overview
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Address assignment and host-to-host,
host-to-router, and router-to-host
automatic tunneling technology
ISATAP addresses:
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[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
Understanding IPv6
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Link-Local ISATAP Configuration
ISATAP Host A
FE80::5EFE:10.40.1.29
IPv4
Infrastructure
ISATAP Host B
FE80::5EFE:192.168.41.30
Understanding IPv6
Slide: 24
ISATAP Router Configuration
Example prefix: 3FFE:2900:D005:7::/64
IPv6
network
IPv4
Infrastructure
ISATAP
Router
ISATAP Host B
3FFE:2900:D005:7:5EFE:192.168.41.30
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ISATAP router
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Responds to tunneled router solicitations from
ISATAP hosts
Forward traffic between ISATAP hosts and other
IPv6 subnets
Understanding IPv6
Slide: 25
ISATAP and 6to4 Example
ISATAP Host A
2002:9D36:1:2:0:5EFE:192.168.12.9
192.168.12.9
Site A
IPv4
Infrastructure
Part 1
192.168.204.1
6to4 Router A
IPv6/IPv4
157.54.0.1
Internet
Part 2
131.107.0.1
6to4 Router B
IPv6/IPv4
192.168.39.1
Site B
IPv4
Infrastructure
Part 3
192.168.141.30
ISATAP Host B
2002:836B:1:2:0:5EFE:192.168.141.30
Understanding IPv6
Slide: 26
PortProxy Service
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TCP proxy for:
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IPv4 to IPv4
IPv4 to IPv6
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IPv4-only host can communicate with IPv6-only server or
application
IPv6 to IPv6
IPv6 to IPv4
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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
Understanding IPv6
Slide: 27
PortProxy Coexistence Scenarios
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An IPv4-only node can access an IPv6only node
An IPv6-only node can access an IPv4only node
An IPv6 node can access an IPv4-only
service running on an IPv6/IPv4 node
Understanding IPv6
Slide: 28
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
Understanding IPv6
Slide: 29
Review
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Coexistence and migration overview
Coexistence mechanisms
Tunneling configurations
6over4
6to4
ISATAP
PortProxy
Migrating to IPv6
Understanding IPv6
Slide: 30