information and risk-driven verification an innovative ... · information and risk-driven...

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March 20, 2014

DPG Annual Meeting, Berlin

C. Listner, M.J. Canty, A. Rezniczek, G. Stein, I. Niemeyer

Information and Risk-driven

Verification – An Innovative

Approach?

July 11, 2013 Slide 2

1. Introduction

2. Acquisition path analysis & IAEA’s requirements

3. Our methodology

4. A comparative example

5. Nuclear disarmament

6. Summary and outlook

Outline


• Problems

• Declaration‘s completeness

• Safeguards measures too material-oriented

• Effectiveness and Efficiency

• Program 93+2

• Extended Declaration (fuel cycle R&D, export)

• Extended Access (research institutions,

decommissioned facilities)

• Environmental samples

• Open source information, remote sensing

• Optimal usage of possible measures

• Improved mandate under the Additional Protocol

Traditional Safeguards


• Instead of single nuclear processes, consider State as a

whole

• No more process-specific Safeguard goals

• State-specific technical objectives which are applied based

on proliferation risk

• Objective, reproducible, transparent, standardized,

documented → non-discriminatory

• Facts about a State (State-specific Factors)

• State-level Objectives, Technical Objectives

• Applicable to all types of Safeguards agreements

State-level Concept (SLC)


State-level Concept (SLC)


Acquisition Path Analysis

• Acquisition Path (AP): sequence of activities which a State

could consider to acquire weapons usable material

• Acquisition Path Analysis (APA): analysis of all plausible

APs; aim is to determine whether proposed safeguard

measures are sufficient

• Functional requirements

• Visualization

• Reproducibility and automation

• Integration into existing systems and models

• IAEA’s physical model as basis


Physical Model


Acquisition Path Structure

• Starts from an artificial origin node

• First process is diversion or import

• Material is then transformed by processes

• Distinguish between misuse of declared facilities and

clandestine activities

• Acquisition Paths end at direct use material

Example of an Acquisition Path


Mathematical Background

• Physical Model = mathematical graph

• Route planning software

• Finding paths is a solved problem

• Quantifying attractiveness is based on structured expert judgment

Graph Theory Route Planning Acquisition Path

Analysis

Node Location Material form

Edge Street Process / path segment

Path Route Acquisition Path

Edge Weight Distance Attractiveness


• Modular process

• Procedure to be implemented as a software tool

New 3-step Approach

a b c

d e

f

inspector

Network

Modelling

Network

Analysis

Strategic

Assessment

inspectee


Network Modeling

• Attractiveness of nuclear processes for the state

• Route planning: shortest, quickest, cheapest way

• GIF: Technical Difficulty (TD), Proliferation Cost (PC),

Proliferation Time (PT)

• Four grades (0..very attractive to 3..very unattractive)

• Overall attractiveness calculated by weighted sum

• Analyst has to make a decision

• Inspection costs

• Technical objectives with underlying safeguards

measures create costs and lead to a probability of

detection (DP)

• Minimization of costs is desirable while preserving

deterrence

1 2 3


• Enumerate all paths and sort them according to their

attractiveness

• Not only the shortest path

• Result of Network Analysis, i.e. a complete set of

technically possible Acquisition Paths ranked by

attractiveness

• Visualization of the paths

• No user interaction needed

Network Analysis

1 2 3


Strategic Assessment

• State’s strategies: APs + compliant behavior

• IAEA’s strategies: Technical Objectives

Combination (TOCj)

• Detection probability for path i given TOCj : 1 - βij

• Calculation using product rule on the segment’s

detection probabilities

• Modelling using non-cooperative game theory

• Nash-equilibrium as solution

• No zero-sum game

1 2 3



• State’s payoffs in decreasing order

• Calculation payoff based on path length: di = l1 / li

• Expected payoff (expected benefit - risk)

• Compliance given TOCj: (1 - αj)0 - αjf

• Non-compliance along path i given TOCj: βijdi - (1 - βij)b

1 2 3

Undetected non-compliant behavior along path 1 di

… …

Undetected non-compliant behavior along path n dn

compliant behavior w/o false alarm 0

compliant behavior with false alarm -f

Detected non-compliant behavior along any path -b



• IAEA’s payoff in decreasing order

• Expected payoff (expected benefit - risk)

• Compliance given TOCj: (1 - αj)0 - αje

• Non-compliance along path i given TOCj: -βijc - (1 - βij)a

1 2 3

compliant behavior w/o false alarm 0

compliant behavior with false alarm -e

Detected non-compliant behavior along

any path

-a

Undetected non-compliant behavior along

any path

-c



1 2 3

Expected

payoff for

[State, IAEA]

TOC1 … TOCn

AP1

[β11d1-(1-β11)b,

-β11c-(1-β11)a] …

[β1nd1-(1-β1n)b, -

β1nc-(1-β1n)a]

… … … …

APm

[βm1dm-(1-βm1)b,

-βm1c-(1-βm1)a] …

[βmndm-(1-βmn)b,

-βmnc-(1-βmn)a]

Compliant

behavior [-α1f , -α1e] … [-αnf , -αne]


• None of the two players can improve its payoff by

unilaterally deviating from the equilibrium strategy.

• Equilibrium payoff (H1*,H2

*)

• Not necessarily the maximum payoff for one or both

players

• Lemke-Howson-Algorithm

• Assumptions

• Payoff matrix is known to both players (total

information)

• Players want to achieve high payoffs (rational

behavior)

Nash equilibrium

1 2 3


• State chooses compliant behavior, IAEO chooses TOCj

• H1* = - αjf

• H2 * = - αje

• State would reduce its expected payoff if he chooses any

path

• Expected payoff of a successful nuclear weapon

acquisition – risk of detection < false alarm risk at

compliant behavior

• IAEA increases its false alarm risk if she chooses another

TOC.

• All paths are adequately covered by Safeguards.

Nash equilibrium

1 2 3


• State chooses path i, IAEA chooses TOCj

• H1* = βijdi - (1 - βij)b

• H2 * = - βijc - (1 - βij)a

• State would reduce its expected payoff if he chooses any

other path or compliant behavior

• Expected payoff of a successful nuclear weapon

acquisition – risk of detection > false alarm risk at

compliant behavior

• Optimal for State given TOCj

• Path i is covered by Safeguards measures at best given

the available resources and possible detection

probabilities

Nash equilibrium

1 2 3


• Effectiveness

• Sufficiency of a safeguards approach

• Assess combination of acquisition paths and safeguards

approaches

• Based on IAEA’s payoffs

• Effectiveness = H2*+100%.

• Efficiency

• Minimum cost equilibrium strategy in which the State

behaves compliantly

• Iteration on budget limit W

Effectiveness and Efficiency

1 2 3


• Two States with similar nuclear capabilities

• Some technical differences regarding existing facilities

• Type of commitment is the main difference

• State A with AP & BC → DP=95% for clandestine

• State B w/o AP → DP=20% for clandestine

• Comparing results with respect to

• Number and type of possible Acquisition Paths

• Type of strategies

• Effectiveness of inspectorate

A Comparative Example


State A: Acquisition Model

1 2 3

July 11, 2013 Slide 23 1 2 3

State A: Most Attractive Path

July 11, 2013 Slide 24 1 2 3

State A: 2nd Most Attractive Path

July 11, 2013 Slide 25 1 2 3

State A: 3rd Most Attractive Path

July 11, 2013 Slide 26 1 2 3

State A: Least Attractive Path (#1041)


State B: Acquisition Model

1 2 3

July 11, 2013 Slide 28 1 2 3

State B: Most Attractive Path

July 11, 2013 Slide 29 1 2 3

State B: 2nd Most Attractive Path

July 11, 2013 Slide 30 1 2 3

State B: 3rd Most Attractive Path

July 11, 2013 Slide 31 1 2 3

State B: Least Attractive Path (#814)


• State’s strategies: 1041 + 1 (State A), 814 + 1 (State B)

• Inspectorate’s strategies: any combination out of 16 (State

A) resp. 18 (State B) distinct activities

• Costs associated to TOC’s, Cost threshold W

• Computation of Nash equilibrium incl. effectiveness

• No false alarm probabilities modelled

• State’s payoff parameters: d1 / b = 9 (gain of successful

acquisition to loss of perceived sanctions in case of

detection)

• IAEA’s payoff parameters: c / a = 10 (loss of undetected

non-compliance to loss of detected non-compliance)


1 2 3


Effectiveness

1 2 3


Nuclear Disarmament

• Abstract from IAEA to a general inspectorate

• Two additional edge types

• Diversion from military fuel cycle

• Military processing

• Depending on given commitments:

• Usage of these processes and thus also of some APs

may be compliant

• Modeled via DP=0%

• No modeling of clandestine processes


• Presented a new concept for structured high-level planning

of verification activities

• 3-step

• modular

• can be automated

• Good understanding of the tool‘s operating principles

• Should be seen as a tool assisting the analyst

• Gave an example showing plausible results

• Extension to nuclear disarmament possible

Conclusions / Summary


Outlook

• Detection probabilities for clandestine processes (“There

are known knowns ... But there are also unknown

unknowns” – Donald Rumsfeld)

• Modeling uncertainty

• Case studies from other verification fields

• HCoC

• CWC

• FMCT


Thank you for your

attention.

This research project is funded by

the Federal Ministry of

Economics and Energy (BMWi)

under the German Support

Programme to the IAEA.

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