The document summarizes key concepts in mobile ad hoc networks (MANETs) and vehicular ad hoc networks (VANETs). It discusses routing protocols for MANETs such as DSDV, CGSR, AODV and DSR. It then covers challenges and security requirements for VANETs, including message authentication, non-repudiation, and privacy. The system model involves vehicles, roadside infrastructure, and authorities communicating through frequent broadcast messages with time sensitivity.

1. POWER POINT PRESENTATION
NAME : MAHESHWARAND
DEPT : CSE-A3ND YEAR
SUB CODE : CS8601
SUBJECT : MOBILE COMPUTING
SUBMITTED DATE : 17 02 2021
REG NO : 810418104059
REFERENCE : www.mc.edu.in

2. Mobile Ad-Hoc
Networking

3. What is a MANET?
• MANET – (Mobile Ad-Hoc NETwork) a system of
mobile nodes (laptops, sensors, etc.) interfacing
without the assistance of centralized infrastructure
(access points, bridges, etc.)
Mobile Ad-Hoc Networking

4. The Problem
• Unstable paths
• Processing power
• Battery life
• Time delays
• High cost of memory

5. Factors Affecting MANETs
• Scalability
• Power vs. Latency
• Incompatible Standards
• Data Rates
• User Education
• Security
• Coverage

6. Solutions
• Table Driven
• DSDV
• CGSR
• WRP
• Source-initiated On-Demand Driven
• AODV
• DSR
• LMR
• TORA
• ABR
• SSR

7. The Family Tree

8. Destination-Sequenced Distance-Vector Routing
(DSDV)
• Every node maintains a routing table.
• “Full” vs. “incremental” update
• Settling time – the weighted average time that routes to a destination
will fluctuate before the route with the best metric is received.

9. Clusterhead Gateway Switch Routing (CGSR)
• A central “clusterhead” node is chosen.
• The clusterhead is chosen by the “Least Cluster Change” algorithm
• Traffic is routed to the current clusterhead who forwards the traffic
through a gateway node to the next clusterhead in line until the
clusterhead of the destination node is located.
• Each node must maintain a cluster member table

10. CGSR (cont.)

11. Wireless Routing Protocol (WRP)
• 4 tables: Distance, routing, link-cost, and message retransmission list
• Neighboring nodes broadcast update messages
• Uses hello messages to establish connectivity
• Checks all incoming update information

12. Comparing Table Driven Routing Protocols

13. Ad-hoc On-demand Distance Vector Routing
(AODV)
• Route Request Packets (RREQ)
• The source node broadcasts an RREQ to all neighboring nodes.
• Nodes record the source of the first RREQ received to establish a
reverse path.

14. AODV (cont.)
• Route Reply Packets (RREP)
• The destination or node with a route to the destination unicasts a RREP
back to the source to establish a route.

15. Dynamic Source Routing (DSR)
• Each node maintains a route cache.
• If a source node has no route in its cache, it broadcasts a route
request.
• A route reply is generated when either the destination or a node with
a route to the destination is found.
• Supports symmetric links

16. DSR (cont.)
• Maintenance is accomplished by route error packets and
acknowledgements.
• If a node fails to send an acknowledgement, any route that contains that
node is truncated.

17. Temporally-Ordered Routing Algorithm (TORA)
• Used in highly dynamic networks
• Provides multiple routes for source/destination pair
• Uses direct acyclic graphs to measure “height”
• Assumes all nodes have synchronized clocks
• Classifies links as upstream and downstream

18. TORA (cont.)

19. Associativity-Based Routing (ABR)
• Uses degree of association stability as a metric
• Strives to build “longer-lived” routes

20. Signal Stability Routing (SSR)
• Selects routes based on signal strength and location stability
• Periodic beacons update signal strength tables
• Only requests that are received over strong channels are forwarded
unless the PREF field in the header is set to allow weak channels

21. Comparing Source-Initiated On-Demand Routing
Protocols

22. Vehicular Ad–Hoc
Network

23. 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

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

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

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

27. Related work
Research have been worked
Outline challenges for VANET
- availablility, mobility
Describe particular attacks
-DoS, alteration attacks
Suggest solution towards attacks

28. 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

29. Security Requirements
Message Authentication and Integrity
- Message must be protected from any
alteration
Message Non-Repudiation
- The sender of a message cannot deny having sent a
message
Entity Authentication
- The receiver is ensured that the sender generated a
message
- The receiver has evidence of the liveness of the sender

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

31. System Model
 Users
- user is the owner or the
driver or a passenger
of the vehicle
 Network Nodes
- processes running on computing platforms
capable of wireless communication
- Mounted on vehicles and road-side units
(RSUs)

32. Communication Model
Frequent Broadcast Communication
Most of the vehicular network traffic is Broadcasted at the network
or application layers
Message are transmitted either
periodically or triggered by network events
Transmission period is low
Time-sensitive Communication
Message delivery can be constrained by deadlines
- different messages have different delay requirements