VANET PRE.ppt

for study

1. VANET
Presented by: Ramu G

2. Outline
Introduction
Security Requirements
System Model
Communication Model
Adversary Model
Design Principles

4. What is VANET
Vehicular Ad–Hoc Network, or VANET
a form of Mobile ad-hoc network
provide communication
-among nearby vehicles
-between vehicles
-nearby fixed equipment

5. Introduction
How vehicular communications work
-road-side infrastructure units(RSUs),
named network nodes, are equipped
with on-board processing and wireless
communication modules

6. How vehicular communications work
(Continue)
-vehicle-to-vehicle (V2V)and vehicle-to-infrastructure
(V2I)communication will be possible

8. What can VANET provide ?

9. Warnings!!!

10. Warnings!!!

11. traffic and road conditions

12. traffic and road conditions

15. What can VANET provide
The VANET can provide
Safety
Efficiency
Traffic and road conditions
Road signal alarm
Local information

16. Related work
Research have been worked
Outline challenges for VANET
-availablility, mobility
Describe particular attacks
-DoS, alteration attacks
Suggest solution towards attacks
This paper provide a basis for the development
of future vehicular security schemes

17. Security Requirements

18. SECURITY

19. Security Requirements
1.Message Authentication and Integrity
2.Message Non-Repudiation
3.Entity Authentication
4.Access Control Authorization
5.Message Confidentiality
6.Privacy and Anonymity
7.Availability
8.Liability Identification

20. Security Requirements
Message Authentication and Integrity
-Message must be protectedfrom any
alteration
Message Non-Repudiation
-The sender of a message cannot denyhaving sent a
message
Entity Authentication
-The receiver is ensured that the sender generated a
message
-The receiver has evidence of the livenessof the sender

21. Security Requirements
Access Control
-determined locally by policies
-authorization established what each
node is allowed to doin the network
Message Confidentiality
-the content of a message is kept
secret from those nodes that are not
authorized to access it

22. Security Requirements
Privacy and Anonymity
-vehicular communication (VC)
systems should not disclose
any personal and private
information of their users
-any observers should not knowany future
actions of other nodes
-anonymitymay not bea reasonable requirement
for all entities of the vehicular communications
system

23. Security Requirements
Availability
-protocols and services should remain
operationaleven in the presence of
faults, malicious or benign
Liability Identification
-users of vehicles are liable for their deliberate or
accidental actions that disrupt the operation of other
nodes

24. System Model

25. System Model
Vehicular communications system
-Users
-Network nodes
-Authorities

26. System Model
Note. From “Securing Vehicular Communications –Assumptions, Requirements, and Principles,” by P. Papadimitratos,
V. Gligor, J-P Hubaux, In Proceedings of the Workshop on Embedded Security in Cars (ESCAR) 2006, November
2006.

28. System Model
Users
-user is the owneror the
driveror a passenger
of the vehicle
Network Nodes
-processes running on computing platforms
capable of wireless communication
-Mounted on vehiclesand road-side units
(RSUs)

29. System Model
Authorities
-public agenciesor
corporationswith
administrative powers
-for example, city or state
transportation authorities

30. System Model
VC system operational assumptions
1.Authorities
2.Vehicle Identification and Credentials
3.Infrastructure Identification and Credentials
4.User Identification and Credentials
5.User and Vehicle Association
6.Trusted Components

31. System Model
Authorities
-trusted entities or nodes
-issuingand manageidentities and
credentials for vehicular network
-establish two-way communication with nodes
Vehicle Identification and Credentials
-unique identity V
-a pair of private and public keys, k
vand K
V
-certificate Cert
X{K
V, A
V}issued by
authority X
-Vdenotes on-board central
processing and communication
module

32. System Model
Note. From “Securing Vehicular Communications –Assumptions, Requirements, and Principles,” by P.
Papadimitratos, V. Gligor, J-P Hubaux, In Proceedings of the Workshop on Embedded Security in
Cars (ESCAR) 2006, November 2006.

33. System Model
Infrastructure Identification and Credentials
-unique identity I
-a pair of private and public key k
Iand K
I
-certificate Cert
Z{K
I, A
I} issued by authority Z
-gatewayto the authorities
-gatewayto the mobile vehicles
-RSUs’locations are fixed
-public vehicles
-considered trustworthy
-be used to assist security
related operations

34. What are public vehicles ?

36. System Model
User identification and Credentials
-Unique identity, U
-a pair of private and public keys, k
U and K
U
-Certificate Cert
Y{K
U, A
U} issued by authority Y
User and Vehicle Association
-user is the owneror the driveror a
passengerof the vehicle
-assume only oneuser can operate
a vehicle
-assume the user is the driver

37. System Model
Trusted Components (TCs)
-nodes equipped with trusted components, i.e., built-in
hardware and firmware
-TCs enforce a policy on the interaction with
the on-board software
-Accessto any information stored in the TCs and
modification of their functionality can be done only
by the interface provided by the TCs.
-perform cryptographic operationswith signature
generations and verifications

38. Communication Model

39. Communication Model
Model the wireless communicationin
vehicular networks, whose connectivitycan
change frequently
Focus mainly on the data link layer

40. Communication Model
Data-link layer primitives and assumption
Send
L(V,m) : transmits message mto node Vwithin
radius Rof the transmitting node
Bcast
L(m) : broadcasts message mto all nodes
within radius Rof the transmitting node
Receive
L(m) : receives message mtransmitted by a
node within radius Rof the receiver
 A link(W,V) exists when two nodes Wand
Vare able to communicate directly

41. Communication Model
Linksare either up or down, and their state does not
change faster than the transmission time of a single
packet
The network connectivity, at a particular
instance in time. Modeled as the graph G
the edges of which are all up links.
Transmissionsfrom Ware received by all nodes Vsuch
that (W, V
i) is up during the entire duration of the packet
transmission
Packetsare delivered across an up link
within a maximum link delay τ or they are
not delivered at all.

42. Communication Model
Communication across the network is
dependent on
availability of sufficient resources
bandwidth
-shared medium contend
-bandwidth can fluctuate
-unevenly distributedamong neighbors
-links may be congested

43. Communication Model
Communication Radius, R
Varyover time
Different classes of nodes may operate with different R
Multi-domain and Highly Volatile
environment
Nodes are not bound to administrative and geographical
boundaries
Any two or more nodes communicate independently

44. Communication Model
Frequent Broadcast Communication
Most of the vehicular network traffic is Broadcastedat the
network or application layers
Message are transmitted either
periodicallyor triggeredby network events
Transmission periodis low
Time-sensitive Communication
Message delivery can be constrained by deadlines
-different messages have different delay requirements

45. Adversary Model

46. Adversary Model
Network nodes
-correct or benign
-faulty or adversaries
-external adversaries
-Internal adversaries
-active adversaries
-passive adversaries

47. faulty is not always malicious!!!

48. Adversary Model
Internal Active
Adversaries
Multiple adversarial nodes
-adversaries are
independent
-adversaries can collude
-based on TCs, colluding
adversaries are
prevented from exchanging
cryptographic material and
credentials

49. Adversary Model
Internal Active Adversaries (continue)
non-adaptive adversaryAdversarial nodes are fixed
adaptive adversaryAdversarial nodes change over time
Computationally bounded adversary
adversaries are computationally limited
-limited resources and computational power
-the knowledgeof an adversary is limited
-memoryfinite