Re: [Model-t] What are we trying to protect

Thomas Hardjono <hardjono@mit.edu> Tue, 06 August 2019 21:45 UTC

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From: Thomas Hardjono <hardjono@mit.edu>
To: "model-t@iab.org" <model-t@iab.org>
Thread-Topic: [Model-t] What are we trying to protect
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Date: Tue, 06 Aug 2019 21:45:23 +0000
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Subject: Re: [Model-t] What are we trying to protect
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>>> 1) Attacking the system directly.

>>> 2) Delivering an attack through a user-initiated session or exfiltrating data through said session

>>> 4) Passive monitoring of all traffic

>>> 5) Monitoring and tracking all user's traffic inside their session. 


Historically the IETF has focused on protocols and communications security. This was an explicit choice/decision of the IETF community in the mid-1990s. So, all the protocols we have (ISAKMP, IKE, IPsec, TLS, etc.) have addressed a threat model that was focused on the communications channel. The security of the end-point, such as a Client or device, was out of scope (until now, I guess, depending).

If the IETF’s scope is going to be expanded, I’d suggest the IETF developing an abstraction model and terminology that helps discussion. Otherwise we end up boiling the ocean with too many words, use-cases and scenarios.

At the Montreal SAAG meeting I mentioned the term end-point “state”.  One way to map the above list of threats would be to express it abstractly in terms of state and the protection of state information/data. So, the above list could be mapped to something like this:

(i) Unauthorized modification of end-point state. (i.e. attacking a client OS.).

(ii) Unauthorized exfiltration of end-point state information (i.e. exfiltration of data, both system-data and user-data, from a machine).

(iii) Malicious substitution of state in transit (i.e. hi-jacking a connection and doing a MITM).

(iv) Unhindered reporting of end-point state information (i.e. authentic reporting from a MIB in a device).


You get my point. It’s no longer just about protection of the communication channel and transport protocol resiliency.  It’s now about the “stuff” at the end of the channel.


— thomas —