Subject: Re: [mobile-ip] Design team note: Why the "one bit" is needed andwhy it is sufficient

From: Erik Nordmark <[email-masked]>
Date: Mon, 4 Mar 2002 12:02:20 +0100 (CET)

> I think allowing the network administrator of the network where the HA
> is located to control whether
> MNs that use that HA have an RR or non-RR address would be the more
> common case. The MN
> will get its HoA from that network anyway. Also, a network administrator
> would be in a better position to
> trace any attacks should they be attempted via the HA. The MN may not be
> in a position to even
> know if the HA is getting probed. Also, if a PKI or AAA-based solution
> is in use, the home network must co-operate to provide the appropriate
> cryptographic assurances.

Jim,

I suspect there are multiple types of policy where the service provider
is in a better position to set the policy, as well as cases when a
user should be able to override the policy.

In general we don't have many IETF protocols to help with this - the
only reasonably complete example I can think of is DHCP.
But using a protocol (whether DHCP or something else) to control security
relevant policy on the host has bootstrapping issues.
In some cases this can also be done at subscription time i.e. signing
up with a service provider might mean that the host gets suggested
and/or mandatory policy settings (in the "dialer" software, or in the SIM
card).

So I think for security reasons we want the MN to be the entity stating
the policy whether or not it has received that policy as
a recommendation or a requirement from the service provider.

   Erik