The applications where mobile ad hoc networks are connected to the Internet are gaining popularity. However, several technologies should be applied in order to guarantee a reliable connectivity. Particular cares should be applied to the gateway discovery process. The enhancements related to the gateway discovery process are mainly achieved by controlling the propagation of the gateway messages in the network. Two specific parameters need to be controlled in this process: the frequency of the messages and the area in which they are propagated. This chapter explains how these two parameters are tuned to adapt to the dynamic characteristics of the network. Although the techniques are proposed for the integration of a MANET into the Internet, its applicability could be extended to any other mechanism where broadcast messages are used in a multihop wireless communication.

Chapter Contents:

• 4.1 Introduction: MANETs connected to the Internet
• 4.2 Requirements for connecting a MANET to the Internet
• 4.3 Internet-gateway discovery in a MANET
• 4.4 Techniques to adjust the frequency of the gateway messages
• 4.4.1 Adaptive discovery based on quality of service
• 4.4.2 Algorithm based on the stability factor
• 4.4.3 Fuzzy-logic-based adaptive algorithm
• 4.5 Techniques to adjust the scope of the gateway messages
• 4.5.1 Maximal source coverage
• 4.5.2 Maximal benefit coverage
• 4.5.3 Low overhead and scalable proxied
• 4.5.4 Mobile-IP-based adaptive discovery
• 4.5.5 Centralized TTL adaptation
• 4.5.6 Load-based gateway discovery
• 4.5.7 Signal-to-noise-based adaptation
• 4.5.8 Adaptive distributed discovery
• 4.5.9 Selective retransmission of the MRA messages
• 4.5.10 Gateway discovery based on stable links
• 4.5.11 Type-2 fuzzy-logic-based adjustment
• 4.6 Adjustment in the hybrid gateway discovery
• 4.6.1 Generic algorithm
• 4.6.2 Regulated mobility degree
• 4.6.3 Auto-regressive-filter-based algorithm
• 4.6.4 Adaptive discovery based on the neighbourhood
• 4.6.5 GPS-assisted hybrid gateway discovery
• 4.6.6 Fuzzy-logic-based hybrid gateway discovery
• 4.7 Further developments
• 4.8 Conclusion
• References

Inspec keywords: Internet; mobile ad hoc networks; telecommunication network reliability; message passing; internetworking; broadcasting

Other keywords: messages broadcast; mobile ad hoc networks; multihop wireless communication; network dynamic characteristics; MANET; connectivity reliability; messages frequency; INT Internet-gateway discovery; gateway messages propagation

Subjects: Computer communications; Other computer networks; Mobile radio systems; Reliability