Cisco Cisco IOS Software Release 12.4(2)XB6

© 2006 Cisco Systems, Inc. All rights reserved.

The Mobile IP Support for RFC 3519 NAT Traversal on the Mobile Router feature extends support for 
Network Address Translation (NAT) traversal to the mobile router when the mobile router is in private 
addressing space behind a NAT-enabled device and needs to register directly to the public home agent 
using a private collocated care-of address (CCoA). 

NAT traversal is based on the RFC 3519 specification and defines how Mobile IP should operate to 
traverse networks that deploy NAT within their network. NAT traversal allows Mobile IP to interoperate 
with networks that have NAT enabled by providing an alternative method for tunneling Mobile IP data 
traffic. New extensions in the Mobile IP registration request and reply messages have been added that 
establish User Datagram Protocol (UDP) tunneling. 

Your Cisco IOS software release may not support all of the features documented in this module. To reach 
links to specific feature documentation in this module and to see a list of the releases in which each feature is 
supported, use the 

Use Cisco Feature Navigator to find information about platform support and Cisco IOS and Catalyst OS 
software image support. To access Cisco Feature Navigator, go to 

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