IPv6

1
IPv6

• Using IPv6 and IPv4
• Integration and Co-existence

2
Integration and Co-existence Strategy

• The transition from IPv4 to IPv6 does not require
  an upgrade on all nodes at the same time.
• Many transition mechanisms enable smooth
  integration of IPv4 to IPv6.
• There are mechanisms available that allow IPv4
  nodes to communicate with IPv6 nodes.
• All of these mechanisms can be applied to
  different situations.

3
Integration Methods

• Dual Stack (Dual IP)
• Complete support for both Internet protocols,
  IPv4 and IPv6, in hosts and routers.
• Most preferred mechanism.
• Tunnelling Techniques
• The encapsulation of packets of one IP version
  number within packets of a second IP version
  number in order to traverse clouds of the second
  IP version number.
• Translation Techniques
• Enables IPv6-only devices to communicate with
  IPv4-only devices and vice versa.
• Least desirable set of mechanisms.

4
Dual Stack
5
Dual Stack

• Conceptually easiest ways of introducing IPv6 to
  a network is called the dual stack mechanism,
  as described in NG05, which is an update of RFC
  2893 RFC2893.
• A host or a router is equipped with both IPv4 and
  IPv6 protocol stacks in the operating system
  (though this may typically be implemented in a
  hybrid way).
• Each node, called an IPv4/IPv6 node, is
  configured with both IPv4 and IPv6 addresses.
• It can both send and receive datagrams belonging
  to both protocols and thus communicate with every
  node in the IPv4 and IPv6 network.
• Well known and has been applied in the past for
  other protocol transitions.

6
Application Supporting both IPv4 and IPv6 Can use
both stacks
7
Stack Selection

• Dual-stack node itself can not randomly decide to
  use one of the two stacks to communicate.
• Two methods to force a dual-stack node to use
  its IPv6 stack
• Manual entry by the user
• Using a naming service

8
Stack Selection Manual entry by the user

• If the user knows the IPv6 address of the
  destination IPv6 hostname, can fill in the IPv6
  address to establish the session
• The legal format of IPv6 must be used
• This method is good enough for debugging but best
  for daily use of applications.

9
Stack Selection Using a Naming service

• By configuring FQDN in DNS with IPv4 and IPv6
  addresses
• An FQDN may be available through one IPv4 address
  represented by an A record or through one IPv6
  address represented by an AAAA record in the DNS
  server.
• The same FQDN might be available with both IPv4
  and IPv6 addresses.
• DNS servers can be queried to provide information
  about a servers availability and host service
  either over IPv4 or IPv6.
• As defined in RFC 2553, Basic Socket Interface
  Extensions for IPv6, a new API is defined to
  handle both IPv4 and IPv6 in DNS queries.
• The functions gethostbyname and gethostbyaddr in
  applications must be modified to get the benefits
  of the IPv6 protocol in legacy IPv4-based
  applications.

10
Stack Selection Using a Naming servicePossible
querying scenarios

• Querying for an IPv4 address
• A record
• Querying for an IPv6 Address
• AAAA record
• Querying for all types of Addresses
• First look for an AAAA record, if not
• Then look for an A record

11
Querying the Naming Service for an IPv4 Address

• When an application is IPv4 aware only, it asks
  the DNS server to get only the IPv4 address for
  the host name to communicate.

12
Querying the Naming Service for an IPv6 Address
IPv6 application requesting an FQDN AAAA record
from DNS

• Application may also support IPv6 only. It asks
  the DNS server to resolve an FQDN to get the host
  name s IPv6 address to communicate.

13
Querying the Naming Service for all types of
Addresses

• Application first looks for AAAA record. If does
  not find one, it looks for an A record to
  communicate with a host name.
• Application supporting both is coded to give
  preference to IPv6 address received from DNS

14
Enabling Dual Stack on Cisco routers

• When both IPv4 and IPv6 addresses are assigned
  to a network interface, the interface is
  considered dual-stacked.

15
Applications supports Dual-Stack on Cisco routers

• DNS Resolver
• It may resolve host names into IPv4 and IPv6
  addresses.
• It can be configured ip name-server ipv6-address
  command. It can accept upto six name servers
• Telnet
• IOS EXEC accepts both IPv4 and IPv6 address as an
  argument
• TFTP server
• IOS EXEC accepts both IPv4 and IPv6 address as an
  argument
• HTTP server
• Accepts incoming sessions over IPv4 and IPv6

16
Tunnelling IPv6 Packets over Existing IPv4 Network

• Note Tunnelling is an intermediate integration
  and transition technique that should not be
  considered a final solution. Native IPv6
  architecture should be the ultimate goal.

17
Why Tunneling?

• Tunnels are generally used on the network to
  carry incompatible protocols or specific data
  over an existing network.
• For deployment of IPv6, it provides a basic way
  for IPv6 hosts or island of IPv6 hosts, servers,
  and routers to reach other IPv6 island and IPv6
  networks using IPv4 routing domain as the
  transport layer.

Edge routers at the border of the IPv6 islands
and the Internet can handle the tunnelling of
IPv6 packets in IPv4. Tunnelling can be
configured between border routers or between a
border router and a host however, both tunnel
endpoints must support both the IPv4 and IPv6
protocol stacks.
18
How Does Tunnelling IPv6 Packets in IPv4 Work?

• Tunnelling encapsulates IPv6 packets in IPv4
  packets for delivery across an IPv4
  infrastructure (a core network or the Internet).
• When IPv6 packets are tunneled in IPv4, their
  original header and payload are not modified.
• One IPv4 header is inserted over the IPv6 header.
• At each side of the tunnel, encapsulation and
  decapsulation of IPv6 packets are performed.
• Edge device must support both IPv4 and IPv6.

19
IPv6 Packets Delivered Through IPv4 Tunnel
20
Issues with Tunnelling

• Tunnel MTU and Fragmentation
• IPv4 header 20 octets is inserted before the
  IPV6 packet ? decreasing IPv6 effective MTU by 20
  octets
• Min IPv6 MTU 1280 octets
• Due to fragmentation of IPv6 leads to
  performance issues
• Handling IPv4 ICMPv4 errors
• Filtering Protocol 41
• NAT

21
IPv6 Tunneling Scenarios in IPv4

• Host-to-host
• Isolated hosts with a dual stack on an IPv4
  network can establish a tunnel to another
  dual-stack host.
• Allows the establishment of end-to-end IPv6
  sessions between hosts
• Host to router
• Isolated hosts with a dual stack on an IPv4
  network can establish a tunnel to the dual-stack
  router
• Router to router
• Routers with a dual-stack on an Ipv4 network can
  establish a tunnel to another dual-stack router.

22
IPv6 Tunneling Scenarios in IPv4
23
Isolated Dual-Stack Host

• Encapsulation can be done by edge routers between
  hosts or between a host and a router.

24
Deploying Tunnels

1. Configured Tunnels (Manual)
2. Tunnel Broker
3. Tunnel Server
4. 6to4
5. GRE Tunnels
6. Intra-Site Automatic Tunnel Addressing Protocol
   (ISATAP)
7. Automatic IPv4-compatible tunnel

25
1. Configured Tunnels (Manual)

• The very first transition mechanism supported by
  IPv6
• Configured tunnels are enabled and configured
  statically on dual-stack nodes.
• A manually configured tunnel is equivalent to a
  permanent link between two IPv6 domains over an
  IPv4 backbone.
• The primary use is for stable connections that
  require regular secure communication between two
  edge routers or between an end system and an edge
  router, or for connection to remote IPv6
  networks.
• The host or router at each end of a configured
  tunnel must support both the IPv4 and IPv6
  protocol stacks.

26
1. Configured Tunnels (Manual) contd.

• An IPv6 address is manually configured on a
  tunnel interface, and manually configured IPv4
  addresses are assigned to the tunnel source and
  the tunnel destination.
• Manually configured tunnels can be configured
  between border routers or between a border router
  and a host.
• On each side of a configured tunnel, IPv4 and
  IPv6 addresses must be assigned manually to
  configure the tunnel interface.
• Local IPv4 address
• Used as the source IPv4 address for outbound
  traffic
• Far-end IPv4 address
• Used as the destination IPv4 for outbound traffic
• Local IPv6 address
• Assigned locally to the tunnel interface

27
Enabling configured Tunnels on Cisco
28
Addresses Assigned to a configured Tunnel
Interface

• IPv6 addresses assigned to both ends of the
  tunnel are within the same subnet
• IPv6 routing must be configured properly to
  enable forwarding of IPv6 packets between the two
  IPv6 networks.

29
Enabling a Configured Tunnel Example
30
Example of a Configured Tunnel - 1
31
2. Tunnel Broker

• It is an external system, rather than a router
  that acts as a server on the IPv4 networks and
  that receives requests for tunnelling from
  dual-stack nodes.
• Requests are sent over IPv4 by dual-stack nodes
  to the tunnel broker using HTTP.
• End users can fill a webpage to request a
  configured tunnel
• The tunnel-broker sends back information over
  HTTP to the dual-stack nodes such as the IPv4
  addresses, IPv6 addresses, default IPv6 routes to
  apply for the establishment of a configured
  tunnel to a dual-stack router.
• Tunnel-broker remotely applies commands on a
  dual-stack router to enable a configured tunnel.

32
2. Tunnel Broker
33
3. Tunnel Servers

• Simplified mode of tunnel broker considered an
  open model
• It combines the broker and dual-stack router in
  the same system.
• Request method is still HTTP over IPv4
• Dual-stack host on an IPv4 network reaches tunnel
  server using HTTP
• End user fills the web form and receives the
  config.
• End user applies the configuration to his
  dual-stack host to enable configured tunnel

34
3. Tunnel Servers
Tunnel server locally applies the far-end
configuration of the configured tunnel. At this
time, when the configuration is applied on the
both ends, configured tunnel is fully established
and can be used.
35
4. 6to4 Tunnels

• An automatic 6to4 tunnel may be configured on a
  border router in an isolated IPv6 network, which
  creates a tunnel on a per-packet basis to a
  border router in another IPv6 network over an
  IPv4 infrastructure.
• The key difference between automatic 6to4 tunnels
  and manually configured tunnels is that the
  tunnel is not point-to-point it is
  point-to-multipoint.
• Connection of IPv6 Domains via IPv4 Clouds
  without Explicit Tunnels", provides a solution to
  the complexity problem of using manually
  configured tunnels by specifying a unique routing
  prefix for each end-user site that carries an
  IPv4 tunnel endpoint address

36
Automatic 6to4 Tunnels

• The simplest deployment scenario for 6to4 tunnels
  is to interconnect multiple IPv6 sites, each of
  which has at least one connection to a shared
  IPv4 network.
• This IPv4 network could be the global Internet or
  a corporate backbone.
• The key requirement is that each site have a
  globally unique IPv4 address the Cisco IOS
  software uses this address to construct a
  globally unique 6to4/48 IPv6 prefix.
• As with other tunnel mechanisms, appropriate
  entries in a Domain Name System (DNS) that map
  between hostnames and IP addresses for both IPv4
  and IPv6 allow the applications to choose the
  required address.

37
6to4 Tunnels
38
Characteristic

• Automatic Tunneling
• Tunneling of IPv6 packets between 6to4 sites is
  done dynamically according to the destination
  IPv6 addresses of packets originating from IPv6
  nodes on 604 sites.
• Enabled at the Edge of the site
• 6to4 should be enabled in border routers at the
  edge of sites.
• 6to4 routers must be able to reach other 6to4
  sites and 6to4 routers using IPv4 routing
  infrastructure
• Automatic prefix assignment
• Provides one aggregatable global unicast IPv6
  prefix to each 6to4 site based on the 2002/16
  address space
• Each 6to4 site uses on globally unicast IPv4
  address assigned on a router
• This Ipv4 address is converted into hexadecimal
  format and is appended to the 2002/16 prefix
• Final representation 2002ipv address/48
• Each site gets one /48 prefix.

39
6to4 routers
40
End-to-End IPv6 session Between IPv6 hosts
Through 6to4 Routers
41
Enabling 6to4 Router Configuration on Cisco
42
Enabling 6to4 Router Configuration on Cisco
(contd.)
43
Enabling 6to4 Router Configuration on Cisco
Example
44
ACL Rule

• No IP ACL denying protocol 41.
• With 6to4, following ACLs are recommended
• Inbound ipv4 packets with protocol 41 from any
  source address on the IPv4 Internet
• permit 41 any host 132.214.1.10 (incoming 6to4
  traffic)
• permit 41 host 132.214.1.10 any (outgoing 6to4
  traffic)

45
6to4 Relay Service

• To allow hosts and networks using 6to4 addresses
  to exchange traffic with hosts using "native"
  IPv6 addresses, "relay routers" have been
  established.
• A relay router connects to an IPv4 network and an
  IPv6 network.
• 6to4 packets arriving on an IPv4 interface will
  have their IPv6 payloads routed to the IPv6
  network, while packets arriving on the IPv6
  interface with a destination address prefix of
  2002/16 will be encapsulated and forwarded over
  the IPv4 network.
• A 6to4 relay service is a 6to4 border router that
  offers traffic forwarding to the IPv6 Internet
  for remote 6to4 border routers.
• A 6to4 relay forwards packets that have a
  2002/16 source prefix.
• 6to4 tunnels and connections to a 6to4 relay
  service need not be requested or negotiated
  between customers and the ISP.

46
6to4 Relay Service

• To allow a 6to4 router to communicate with the
  native IPv6 Internet, it must have its IPv6
  default gateway set to a 6to4 address which
  contains the IPv4 address of a 6to4 relay router.
• To avoid the need for users to set this up
  manually, the 6to4 relay anycast address of
  192.88.99.1 (which when wrapped in 6to4 with the
  subnet and hosts fields zero becomes
  2002c0586301) has been allocated for the
  purpose of sending packets to a relay router.
• For routing reasons the whole of 192.88.99.0/24
  has been allocated for routes pointed at 6to4
  relay routers that use the anycast IP.
• Providers willing to provide 6to4 service to
  their clients or peers should advertise the
  anycast prefix like any other IP prefix, and
  route the prefix to their 6to4 relay.

47
Configuring 6to4 Relay Service

• Anycast IPv4 prefix is supported in Cisco IOS.
• Cisco router can act as a 6to4 relay with the
  anycast IPv4 prefix.

48
IPv6-Only-to-IPv4-Only Transition Mechanisms
49
IPv6-Only-to-IPv4-Only Communication

• Networks made of native IPv6 only and IPv4-only
  protocols have to interact and co-exist.
• Full interaction between the two types of
  networks is mandatory to maintain complete
  compatibility between both protocols.
• Examples
• A node in an IPv6-only domain sending an email
  using SMTP to a destination node in an IPv4-only
  domain.
• A node in an IPv4-Only domain replying to the
  source IPv6-Only node in the IPv6 domain.
• Nodes in an IPv4 domain connecting using HTTP to
  a destination web server running in an IPv6
  domain.

50
Methods

• Two methods are used to provide communication
  between IPv6-only and IPv4 only domains
• Application-Level Gateways (ALGs)
• NAT-PT

51
Application-Level Gateways (ALGs)

• ALG technique is a network architecture in which
  gateways with dual-stack support allow nodes in
  an IPv6-only domain to interact with nodes on
  IPv6 only domain

52
Application-Level Gateways (ALGs)

• IPv6 host A establishes an IP session to the
  IPv4-only server B through ALG.
• ALG C maintains one independent session with the
  IPv6 only host A using IPv6 as the transport
  protocol and another independent session with the
  IPv4 only server B over IPv4.
• ALG C converts the IPv6 session into IPv4, and
  vice versa.
• ALG C has dual-stack support.

53
NAT-PT

• Network Address Translation - Protocol
  Translation (NAT-PT) is an IPv6-IPv4 translation
  mechanism, as defined in RFC 2765 and RFC 2766,
  allowing IPv6-only devices to communicate with
  IPv4-only devices and vice versa.
• Before implementing NAT-PT, you must configure
  IPv4 and IPv6 on the router interfaces that need
  to communicate between IPv4-only and IPv6-only
  networks.
• Using a protocol translator between IPv6 and IPv4
  allows direct communication between hosts
  speaking a different network protocol.
• Users can use either static definitions or
  IPv4-mapped definitions for NAT-PT operation.

54
IPv6-Only node A communicates with IPv4-only node
B through a NAT-PT device
55
NAT-PT Operations
56
NAT-PT

• One of the benefits of NAT-PT is that no changes
  are required to existing hosts because all the
  NAT-PT configurations are performed at the NAT-PT
  router.
• NAT-PT should not be used when other native
  communication techniques exist.
• Types of NAT-PT
• Static NAT-PT
• Dynamic NAT-PT
• PAT

57
Static NAT-PT Operation

• Static NAT-PT uses static translation rules to
  map one IPv6 address to one IPv4 address.
• IPv6 network nodes communicate with IPv4 network
  nodes using an IPv6 mapping of the IPv4 address
  configured on the NAT-PT router.
• Static NAT-PT is useful when applications or
  servers require access to a stable IPv4 address.
• Accessing an external IPv4 DNS server is an
  example where static NAT PT can be used.

58
Static NAT-PT Operation

• The NAT-PT device is configured to map the source
  IPv6 address for node A of 20010db8bbbb11 to
  the IPv4 address 192.168.99.2.
• NAT-PT is also configured to map the source
  address of IPv4 node C, 192.168.30.1 to
  20010db8a.
• When packets with a source IPv6 address of node A
  are received at the NAT-PT router they are
  translated to have a destination address to match
  node C in the IPv4-only network.

59
Dynamic NAT-PT Operation

• Dynamic NAT-PT allows multiple NAT-PT mappings by
  allocating addresses from a pool.
• NAT-PT is configured with a pool of IPv6 and/or
  IPv4 addresses.
• At the start of a NAT-PT session a temporary
  address is dynamically allocated from the pool.
• The number of addresses available in the address
  pool determines the maximum number of concurrent
  sessions.
• The NAT-PT device records each mapping between
  addresses in a dynamic state table.
• Dynamic NAT-PT translation operation requires at
  least one static mapping for the IPv4 DNS server.
  

60
Dynamic NAT-PT Operation

• The NAT-PT device is configured with an IPv6
  access list, prefix list, or route map to
  determine which packets are to be translated by
  NAT-PT.
• A pool of IPv4 addresses - 10.21.8.1 to
  10.21.8.10 is configured
• When an IPv6 packet to be translated is
  identified, NAT-PT uses the configured mapping
  rules and assigns a temporary IPv4 address from
  the configured pool of IPv4 addresses.
• After the IPv6 to IPv4 connection is established,
  the reply packets going from IPv4 to IPv6 take
  advantage of the previously established dynamic
  mapping to translate back from IPv4 to IPv6.
• If the connection is initiated by an IPv4-only
  host then the explanation is reversed.

61
Port Address Translation (PAT) or Overload

• PAT allows a single IPv4 address to be used among
  multiple sessions by multiplexing on the port
  number to associate several IPv6 users with a
  single IPv4 address.
• PAT can be accomplished through a specific
  interface or through a pool of addresses.

62
Implementing NAT-PT

1. Configuring Basic IPv6 to IPv4 Connectivity for
   NAT-PT (required)
2. Configuring IPv4-Mapped NAT-PT (required)
3. Configuring Mappings for IPv6 Hosts Accessing
   IPv4 Hosts (required)
4. Configuring Mappings for IPv4 Hosts Accessing
   IPv6 Hosts (optional)
5. Configuring Port Address Translation
6. Verifying NAT-PT Configuration and Operation
   (optional)

63
1. Configuring Basic IPv6 to IPv4 Connectivity
for NAT-PT

• NAT-PT Prefix
• An IPv6 prefix with a prefix length of 96 must be
  specified for NAT-PT to use.
• The IPv6 prefix can be a unique local unicast
  prefix, a subnet of allocated IPv6 prefix, or
  even an extra prefix obtained from ISP.
• The NAT-PT prefix is used to match a destination
  address of an IPv6 packet.
• If the match is successful, NAT-PT will use the
  configured address mapping rules to translate the
  IPv6 packet to an IPv4 packet.
• The NAT-PT prefix can be configured globally or
  with different IPv6 prefixes on individual
  interfaces.
• Using a different NAT-PT prefix on several
  interfaces allows the NAT-PT router to support an
  IPv6 network with multiple exit points to IPv4
  networks.

64
Configuring NAT-PT Prefix

• ipv6 nat prefix ipv6-prefix/prefix-length
• interface type number
• ipv6 address ipv6-prefix /prefix-length
  link-local
• ipv6 nat
• exit
• interface type number
• ip address ip-address mask secondary
• ipv6 nat

65
2. Configuring IPv4-Mapped NAT-PT

• To enable customers to send traffic from their
  IPv6 network to an IPv4 network without
  configuring IPv6 destination address mapping.
• Commands
• interface type number
• ipv6 nat prefix ipv6-prefix v4-mapped
  access-list-name ipv6-prefix
• Example
• Router(config) interface ethernet 3/1
• Router(config-if) ipv6 nat prefix 2001/96
  v4-mapped v4map_acl

66
3. Configuring Mappings for IPv6 Hosts Accessing
IPv4 Hosts

• To configure static or dynamic IPv6 to IPv4
  address mappings.
• The dynamic address mappings include assigning a
  pool of IPv4 addresses and using an access list,
  prefix list, or route map to define which packets
  are to be translated.
• ipv6 nat v6v4 source ipv6-address
  ipv4-addressoripv6 nat v6v4 source list
  access-list-name route-map map-name pool name
• ipv6 nat v6v4 pool name start-ipv4 end-ipv4
  prefix-length prefix-length
• ipv6 nat translation max-entries number
  timeout udp-timeout dns-timeout
  tcp-timeout finrst-timeout icmp-timeout
  seconds never
• ipv6 access-list access-list-name permit
  protocol source-ipv6-prefix/prefix-length
  any host source-ipv6-address operator
  port-number destination-ipv6-prefix/prefix-len
  gth any host destination-ipv6-address
• exit
• show ipv6 nat translations icmp tcp udp
  verbose
• show ipv6 nat statistics

67
ipv6 nat translation command
68
4. Configuring Mappings for IPv4 Hosts Accessing
IPv6 Hosts

• To configure static or dynamic IPv4 to IPv6
  address mappings.
• Commands
• ipv6 nat v4v6 source ipv4-address
  ipv6-addressoripv6 nat v4v6 source list
  access-list-number name pool name
• ipv6 nat v4v6 pool name start-ipv6 end-ipv6
  prefix-length prefix-length
• access-list access-list-name number deny
  permit source source-wildcard log
• Example
• Router(config) ipv6 nat v4v6 source 10.21.8.11
  20010db8yyyy2orRouter(config) ipv6 nat
  v4v6 source list 1 pool v6pool
• Router(config) ipv6 nat v4v6 pool v6pool
  20010db8yyyy1 20010db8yyyy2 prefix-length
  128
• Router(config) access-list 1 permit 192.168.30.0
  0.0.0.255

69
5. Configuring Port Address Translation

• ipv6 nat v6v4 source list access-list-name
  route-map map-name pool name overload
• Router(config) ipv6 nat v6v4 source
  20010db8yyyy11 10.21.8.10
• or
• ipv6 nat v6v4 source list access-list-name
  route-map map-name interface interface name
  overload
• Router(config) ipv6 nat v6v4 source list
  pt-list1 pool v4pool overload
• ipv6 nat v6v4 pool name start-ipv4 end-ipv4
  prefix-length prefix-length
• Router(config) ipv6 nat v6v4 pool v4pool
  10.21.8.1 10.21.8.10 prefix-length 24
• ipv6 nat translation max-entries number
  timeout udp-timeout dns-timeout
  tcp-timeout finrst-timeout icmp-timeout
  seconds never
• Router(config) ipv6 nat translation udp-timeout
  600
• ipv6 access-list access-list-name
• Router(config) ipv6 access-list pt-list1
• permit protocol source-ipv6-prefix/prefix-lengt
  h any host source-ipv6-address operator
  port-number destination-ipv6-prefix/prefix-len
  gth any host destination-ipv6-address
• Router(config-ipv6-acl) permit ipv6
  20010db8bbbb1/64 any

70
Static NAT-PT Configuration Example

• interface Ethernet3/1
• ipv6 address 20010db830029/64
• ipv6 enable
• ipv6 nat
• !
• interface Ethernet3/3
• ip address 192.168.30.9 255.255.255.0
• ipv6 nat
• !
• ipv6 nat v4v6 source 192.168.30.1 20010db802
• ipv6 nat v6v4 source 20010db8bbbb11
  10.21.8.10
• ipv6 nat prefix 20010db80/96

71
Enabling Traffic to be Sent from an IPv6 Network
to an IPv4 Network without Using IPv6 Dastination
Address Mapping Example

• ipv6 nat prefix 2000/96 v4-mapped v4map_acl
• ipv6 access-list v4map_acl
•  permit ipv6 2001/96 2000/96

72
Dynamic NAT-PT Configuration for IPv6 Hosts
Accessing IPv4 Hosts Example

• interface Ethernet3/1
• ipv6 address 20010db8bbbb19/64
• ipv6 enable
• ipv6 nat
• !
• interface Ethernet3/3
• ip address 192.168.30.9 255.255.255.0
• ipv6 nat
• !
• ipv6 nat v4v6 source 192.168.30.1 20010db802
• ipv6 nat v6v4 source list pt-list1 pool v4pool
• ipv6 nat v6v4 pool v4pool 10.21.8.1 10.21.8.10
  prefix-length 24
• ipv6 nat translation udp-timeout 600
• ipv6 nat prefix 20010db81/96
• !
• ipv6 access-list pt-list1
• permit ipv6 20010db8bbbb1/64 any

73
Dynamic NAT-PT Configuration for IPv4 Hosts
Accessing IPv6 Hosts Example

• interface Ethernet3/1
• ipv6 address 20010db8bbbb19/64
• ipv6 enable
• ipv6 nat
• !
• interface Ethernet3/3
• ip address 192.168.30.9 255.255.255.0
• ipv6 nat
• !
• ipv6 nat v4v6 source list pt-list2 pool v6pool
• ipv6 nat v4v6 pool v6pool 20010db801
  20010db802 prefix-length 128
• ipv6 nat v6v4 source 20010db8bbbb11
  10.21.8.0
• ipv6 nat prefix 20010db80/96
• !
• access-list pt-list2 permit 192.168.30.0
  0.0.0.255

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Lab-Exercise

• Case-study Using IPv6 Integration and
  coexistence strategies using Cisco routers

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Q A