April 11 2002 Master Project Presentation 1

Security Issues for Stigmergic Systems

Weilin Zhong

April 11 2002 Master Project Presentation 2

Swarm Intelligence

April 11 2002 Master Project Presentation 3

Swarm Intelligence How can simple individuals achieve

complex group behaviors?

Intelligence lies in Interactions Direct Interaction Indirect Interaction – Stigmergy

April 11 2002 Master Project Presentation 4

Biological Stigmergy Example Ant Foraging Model

April 11 2002 Master Project Presentation 5

Stigmergic Systems Examples:

Network Routing Problems[DiCaro98] Peer-to-Peer network framework[Montresor01] Distributed Intrusion and Response

Systems[Fenet01] Terrain Coverage[Koenig01]

Desirable Characteristics for Survivability Adaptive Decentralized Emergent (Collaborative Group Behaviors)

April 11 2002 Master Project Presentation 6

Stigmergic Systems - Security Challenges

Open-hostile environmentNo Centralized ControlLimited Computational Power

AntNet Security1. What’s AntNet ?2. Threats and Attacks3. Defenses

April 11 2002 Master Project Presentation 7

AntNet AntNet[DiCaro98]

An Adaptive Routing Algorithm Inspired by the stigmergy model in ant

foraging Mobile Multi-Agent Systems - Ants

April 11 2002 Master Project Presentation 8

AntNet Probabilistic Routing Table

Port/dest

N1 N2 … Nn

0->1 P11 P12 … P1n

0->2 P21 P22 … P2n

0->3 P31 P32 … P3n

0

1

2

3

April 11 2002 Master Project Presentation 9

AntNet

1 2 3 4

T4->4 =0T3->4 =L(3,4)+ T4->4

Port/dest

N1 4 … Nn

3->x Px1 Px4 … Pxn

3->2 P21 P24 … P2n

3->4 P41 P44 … P4n

T2->4 =L(2,3)+ T3->4

Port/dest

N1 4 … Nn

2->1 P11 P14 … P1n

2->3 P31 P34 … P3n

2->x Px1 Px4 … Pxn

T1->4 =L(1,2)+ T2->4

Port/dest

N1 4 … Nn

1->2 P21 P24 … P2n

1->x Px1 Px4 … Pxn

1->y Py1 Py4 … Pyn

(N1) (N1, N2) (N1,N2,N3)

(N1, N2, N3, N4)

April 11 2002 Master Project Presentation 10

AntNet: Threats and Attacks

Threats – Compromised Nodes Untrustworthy Hosts Compromised Link

Attack Goals Increase packet latency Decrease Overall Network Throughput Break down a critical node or link Divert packets from certain links

April 11 2002 Master Project Presentation 11

Attack Classes

1. Fabricating Ant Packets2. Dropping Ant Packets3. Tampering With Ant Packets

April 11 2002 Master Project Presentation 12

Fabrication Attack Fabrication

Inject bogus ants Replay ants

Attack Simulation

0

1

2 3

4

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

1

0 100 200 300 400 500 600 700 800 900 1000

Goo

dnes

s

Simulation Time (Sec)

Node 0 Routing Table

0 1

0 2 0 1

0 2

(0234,1.6ms)

…

(0234,4.8ms)

(0)

(01)

(014)(014,0ms)

(014,1.6ms)

(014,3.2ms)

(0)

(02) (023)

(0234)(0234,0ms)

(0234,3.2ms)

(0234,4.8ms)

April 11 2002 Master Project Presentation 13

Fabrication -- Defense Unique Identifier

<source, id> ID Checking and Time out

Defense Simulation

3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6

4.8

0 100 200 300 400 500 600 700 800 900 1000

Ave

rage

Pac

ket L

aten

cy (m

s)

Simulation Time (Sec)

AntNet Packet Latency

bogus ants

defense bogus ants

April 11 2002 Master Project Presentation 14

0

1

2 3

4 5

(01)

Dropping Attacks Dropping Ants

Network Failure Location Limitation

Simulation Results

5

5.5

6.0

6.5

7.0

7.5

8.0

0 100 200 300 400 500 600 700 800 900 1000

Ave

rage

Pac

ket L

aten

cy (m

s)

Simulation Time (Sec)

AntNet Packet Latency

Drop Ants

No Attack (02345,6.4ms)

(0)

(01)

(01)

(0)

(02) (023)

(0234) (02345)(02345,0ms)(02345, 1.6ms)

(02345,3.2ms)(02345,4.8ms)

April 11 2002 Master Project Presentation 15

Tampering Attacks Tampering With

Path Information Trip Time Information

Attack Simulation

0

1

2 3

4

0.0032

0.0034

0.0036

0.0038

0.004

0.0042

0.0044

0.0046

0.0048

0 100 200 300 400 500 600 700 800 900 1000

Ave

rage

Pac

ket L

aten

cy (S

ec)

Simulation Time (Sec)

AntNet Packet Latency

pdel

(0234,0ms)

(0234,1.6ms)(0234,0ms)

(0234,1.6ms)

(0)

(01)

(014)(014,1.6ms)

(014,3.2ms)

(02)

(0)

(023)

(0234)

(014,0ms)

April 11 2002 Master Project Presentation 16

Tampering Attacks - Locality

0

1

2 3

4

5

Locality of Damages

April 11 2002 Master Project Presentation 17

Tampering Attacks - Locality

Locality of Damagess

0

1

2 3

4

5

(0)

(01)

(014)(014,0ms)

(014,1ms)

(014,2ms)

(0)

(02) (023)

(0234)(0234,0ms)

(0234,1ms)(0234,0ms)

(0234,1ms)

April 11 2002 Master Project Presentation 18

Tampering Attacks - Locality

Locality of Damagess

0

1

2 3

4

5

(0)

(01)

(014)(014,0ms)

(014,1ms)

(014,2ms)

(0)

(02) (023)

(0234)(0234,0ms)

(0234,1ms)

(0234,2ms)

(0234,0ms)

April 11 2002 Master Project Presentation 19

Tampering Attacks - Locality

Locality of Damagess

0

1

2 3

4

5

(0)

(01)

(014)(014,0ms)

(014,1ms)

(014,2ms)

(0)

(02) (023)

(02354)(02354,0ms)

(02354,2ms)

(02354,3ms)

(0235)(02354,0ms)(02354,1ms)

April 11 2002 Master Project Presentation 20

Tampering Attacks - Locality

Critical Region

s

DCritical Region

External Node

Internal Node

April 11 2002 Master Project Presentation 21

Tampering Attack -- Defense

Adapted based on [Murphy96, Smith96], Cryptographic Solution

A B C D

{n, A, B}SA {n, B, C}SB

{n, A, B}SA

{n, C, D}SC

{n, B, C}SB

{n, A, B}SA

{X}SK : X signed by node K

{n, ABCD,0}SD

{n, C, D}SC

{n, B, C}SB

{n, A, B}SA

{n, ABCD,0}SD

{n, C, D, TCD}SC

{n, ABCD,0}SD

{n, C, D, TCD}SC

{n, B, C, TBC}SB

{n, ABCD,0}SD

{n, C, D, TCD}SC

{n, B, C, TBC}SB

{n, A, B, TAB}SA

April 11 2002 Master Project Presentation 22

Tampering Attack -- Defense

Lightweight Solutions – Verification Ants

SD

T = (T2 – T1) /2

T = (T2’ – T1)

T2

T2’

{T1}{T1}

{T1}SD{T1}SD

April 11 2002 Master Project Presentation 23

Summary Stigmergic Systems: two-fold factors for security

offer useful properties for security: adaptive, decentralized. offer new opportunities for attackers and challenge

traditional security mechanisms AntNet Security: Resilient to most attacks with

simple defense methods Use unique ids to prevent fabrication attacks Dropping and tampering attacks are only effective for

malicious nodes on the only path Cryptographic techniques usage can be limited by the

locality property