Mobile IPv4 White Paper

Dynamic Key Generation and Distribution
The Diameter Mobile IPv4 protocol allows for the FA to request
the AAAH server to generate dynamic keys for authenticating
messages between the following entities:
o Mobile Node and Home Agent
o Mobile Node and Foreign Agent
o Home Agent and Foreign Agent
Use of dynamically generated keys increases packet security.
Using different keys makes it more difficult for someone
examining network packets to determine a key’s value.
The AAAH encrypts keys for the Mobile Node using the AAA
key or password for the Mobile Node user. While keys for the
Home Agent and Foreign Agent are not encrypted by the AAA
protocol, the AAA messages sent between AAAH and Home
Agent and AAAF and Foreign Agent containing security keys
can be protected by other mechanisms, such as IPSec. Messages
sent between the AAAH and AAAF containing security keys can
be encrypted using security features provided by the AAA
infrastructure.
Dynamic Home Address Allocation
The Base Mobile IP protocol allows a Mobile Node to be
configured without a home address. Home addresses for such
mobile nodes are dynamically allocated during registration
process. HP-UX Mobile IPv4 Home Agents support dynamic
home address allocation for AAA Mobile Nodes. The Home
Agent dynamically allocates addresses from a pool or range of IP
addresses.
Dynamic Home Agent Allocation
HP-UX Mobile IPv4 Home Agent supports dynamic Home
Address allocation for requests authenticated by the AAAH
server. This feature is to support Nodes that do not know their
Home Agent. Home Agent allocation can be done along with
Home Address allocation if required.
HP-UX Mobile IPv4 White Paper 10