Contents

Mobile IP NAT Detect
Finding Feature Information
Restrictions for Mobile IP NAT Detect
How to Configure Mobile IP NAT Detect
Configuring NAT Detect
Verifying the NAT Detect Configuration
Configuration Examples for Mobile IP NAT Detect
Home Agent with NAT Detect Example
Additional References
Command Reference
Glossary

Mobile IP NAT Detect

Last Updated: December 2, 2012

Network Address Translation (NAT) allows an organization with nonglobally routable addresses to connect to the Internet by translating those addresses into globally routable address space. Traditional Mobile IP tunneling has been incompatible with NAT. The Mobile IP--NAT Detect feature is a new service on the home agent that allows it to tunnel traffic to Mobile IP clients with private IP addresses behind a NAT-enabled device. The home agent is now capable of detecting a registration request that has traversed a NAT-enabled device and applying a tunnel to reach the Mobile IP client.

Feature Specifications for the Mobile IP: NAT Detect Feature

Feature History
Release	Modification
12.2(13)T	This feature was introduced.
Supported Platforms
See Feature Navigator.

Finding Feature Information
Restrictions for Mobile IP NAT Detect
How to Configure Mobile IP NAT Detect
Configuration Examples for Mobile IP NAT Detect
Additional References
Command Reference
Glossary

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Restrictions for Mobile IP NAT Detect

This feature is supported for mobile nodes using a collocated care-of address only. Mobile nodes using a foreign agent care-of address behind a NAT gateway cannot be detected by the home agent.

How to Configure Mobile IP NAT Detect

Configuring NAT Detect
Verifying the NAT Detect Configuration

Configuring NAT Detect

To configure NAT detect on the home agent, use the following commands:

SUMMARY STEPS

1. enable

2. configure {terminal | memory | network}

3. router mobile

4. exit

5. ip mobile home-agent [address ip-address][broadcast] [care-of-access access-list] [lifetime number] [nat-detect] [replay seconds] [reverse-tunnel-off] [roam-access access-list] [suppress-unreachable]

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables higher privilege levels, such as privileged EXEC mode. Enter your password if prompted.
Step 2	configure {terminal \| memory \| network} Example: Router# configure terminal	Enters global configuration mode.
Step 3	router mobile Example: Router(config)# router mobile	Enables Mobile IP on the router.
Step 4	exit Example: Router(config-router)# exit	Returns to global configuration mode.
Step 5	ip mobile home-agent [address ip-address][broadcast] [care-of-access access-list] [lifetime number] [nat-detect] [replay seconds] [reverse-tunnel-off] [roam-access access-list] [suppress-unreachable] Example: Router(config)# ip mobile home-agent nat-detect	Enables home agent services and NAT detect.

Verifying the NAT Detect Configuration

To verify that the Mobile IP--NAT Detect feature is working, perform the following steps:

SUMMARY STEPS

1. show ip mobile globals

2. show ip mobile binding

3. show ip mobile traffic

DETAILED STEPS

Command or Action

Purpose

Step 1

show ip mobile globals

Example:

Router# show ip mobile globals

Displays global information for mobile agents.

Step 2

show ip mobile binding

Example:

Router# show ip mobile binding

Displays the mobility binding table.

Step 3

show ip mobile traffic

Example:

Router# show ip mobile traffic

Displays protocol counters.

This command will show the number of successful registration requests using NAT detect.

Configuration Examples for Mobile IP NAT Detect

Home Agent with NAT Detect Example

Home Agent with NAT Detect Example

In the following example, the home agent can detect registration requests from a mobile node behind a NAT-enabled router. The mobile node will use the NAT inside address as the collocated care-of address used in its registration requests.

Home Agent

ip routing 
! 
interface ethernet1 
 ip address 1.0.0.1 255.0.0.0 
! 
interface ethernet2 
 ip address 2.0.0.1 255.0.0.0 
! 
router mobile 
!
router ospf 100 
redistribute mobile subnets metric 1500 
network 1.0.0.0 0.255.255.255 area 0 
network 2.0.0.0 0.255.255.255 area 0 
! 
ip mobile home-agent lifetime 65535 nat-detect replay 255 
ip mobile virtual-network 65.0.0.0 255.0.0.0 
ip mobile host 65.1.1.1 65.1.1.10 virtual-network 65.0.0.0 255.0.0.0 
ip mobile secure host 65.1.1.1 65.1.1.10 spi 100 key hex 12345678123456781234567812345678 
!

Router Configured with NAT

ip routing 
! 
interface ethernet2 
 ip address 2.0.0.2 255.0.0.0 
 ip nat outside 
! 
interface e4 
 ip address 4.0.0.1 255.0.0.0 
 ip nat outside 
! 
! Outside address 2.0.0.101 used for any packet coming from inside 4.0.0.101
! 4.0.0.101 is the collocated care-of address used by MN to register
ip nat inside source static 4.0.0.101 2.0.0.101 
router mobile 
! 
router ospf 100 
network 2.0.0.0 0.255.255.255 area 0 
network 4.0.0.0 0.255.255.255 area 0 
!

Additional References

For additional information related to the Mobile IP--NAT Detect feature, refer to the following sections:

Standards

Standards	Title
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.	--

MIBs

MIBs Link

No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified by this feature.

To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to the Cisco MIB website on Cisco.com at the following URL:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://tools.cisco.com/ITDIT/MIBS/servlet/index

If Cisco MIB Locator does not support the MIB information that you need, you can also obtain a list of supported MIBs and download MIBs from the Cisco MIBs page at the following URL:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

To access Cisco MIB Locator, you must have an account on Cisco.com. If you have forgotten or lost your account information, send a blank e-mail to cco-locksmith@cisco.com. An automatic check will verify that your e-mail address is registered with Cisco.com. If the check is successful, account details with a new random password will be e-mailed to you. Qualified users can establish an account on Cisco.com by following the directions found at this URL:

http://www.cisco.com/register

RFCs

RFCs	Title
No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature.	--

Technical Assistance

Description	Link
Technical Assistance Center (TAC) home page, containing 30,000 pages of searchable technical content, including links to products, technologies, solutions, technical tips, tools, and lots more. Registered Cisco.com users can log in from this page to access even more content.	http://www.cisco.com/public/support/tac/home.shtml

Command Reference

The following commands are introduced or modified in the feature or features documented in this module. For information about these commands, see the Cisco IOS IP Mobility Command Reference at http://www.cisco.com/en/US/docs/ios/ipmobility/command/reference/imo_book.html. For information about all Cisco IOS commands, go to the Command Lookup Tool at http://tools.cisco.com/Support/CLILookup or to the Cisco IOS Master Commands List .

ip mobile home-agent
show ip mobile binding
show ip mobile globals
show ip mobile traffic

Glossary

care-of address --The termination point of the tunnel to a mobile node or mobile router. This can be a collocated care-of address, by which the mobile node or mobile router acquires a local address and detunnels its own packets, or a foreign agent care-of address, by which a foreign agent detunnels packets and forwards them to the mobile node or mobile router.

Note

Refer to the Internetworking Terms and Acronyms for terms not included in this glossary.

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Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.