- Issues in Designing a Transport Layer Protocol for Ad Hoc Wireless Networks
- Design Goals of a Transport Layer Protocol for Ad Hoc Wireless Networks
- Classification of Transport Layer Solutions
- TCP over Ad Hoc Wireless Networks
- Other Transport Layer Protocols for Ad Hoc Wireless Networks
- Security in Ad Hoc Wireless Networks
- Network Security Requirements
- Issues and Challenges in Security Provisioning
- Network Security Attacks
- Key Management
- Secure Routing in Ad Hoc Wireless Networks
9.9 ISSUES AND CHALLENGES IN SECURITY PROVISIONING
Designing a foolproof security protocol for ad hoc wireless is a very challenging task. This is mainly because of certain unique characteristics of ad hoc wireless networks, namely, shared broadcast radio channel, insecure operating environment, lack of central authority, lack of association among nodes, limited availability of resources, and physical vulnerability. A detailed discussion on how each of the above mentioned characteristics causes difficulty in providing security in ad hoc wireless networks is given below.
Shared broadcast radio channel: Unlike in wired networks where a separate dedicated transmission line can be provided between a pair of end users, the radio channel used for communication in ad hoc wireless networks is broadcast in nature and is shared by all nodes in the network. Data transmitted by a node is received by all nodes within its direct transmission range. So a malicious node could easily obtain data being transmitted in the network. This problem can be minimized to a certain extent by using directional antennas.
Insecure operational environment: The operating environments where ad hoc wireless networks are used may not always be secure. One important application of such networks is in battlefields. In such applications, nodes may move in and out of hostile and insecure enemy territory, where they would be highly vulnerable to security attacks.
Lack of central authority: In wired networks and infrastructure-based wireless networks, it would be possible to monitor the traffic on the network through certain important central points (such as routers, base stations, and access points) and implement security mechanisms at such points. Since ad hoc wireless networks do not have any such central points, these mechanisms cannot be applied in ad hoc wireless networks.
Lack of association: Since these networks are dynamic in nature, a node can join or leave the network at any point of the time. If no proper authentication mechanism is used for associating nodes with a network, an intruder would be able to join into the network quite easily and carry out his/her attacks.
Limited resource availability: Resources such as bandwidth, battery power, and computational power (to a certain extent) are scarce in ad hoc wireless networks. Hence, it is difficult to implement complex cryptography-based security mechanisms in such networks.
Physical vulnerability: Nodes in these networks are usually compact and hand-held in nature. They could get damaged easily and are also vulnerable to theft.