Incorporating Security and Energy Efficiency for Multimedia Communications in WANets: A Cross-Layer Design

MANET: Mobile Ad hoc Networks

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  A mobile ad hoc network (MANET), is a self-configuring infrastructureless network of mobile devices connected by wireless links. Ad hoc is Latin and means “for this purpose”.

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  Each device in a MANET is free to move independently in any direction, and will therefore change its links to other devices frequently. Each must forward traffic unrelated to its own use, and therefore be a router. The primary challenge in building a MANET is equipping each device to continuously maintain the information required to properly route traffic. Such networks may operate by them selves or may be connected to the larger Internet.

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  MANETs are a kind of wireless ad hoc networks that usually has a routeable networking environment on top of a Link Layer ad hoc network.

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  The growths of laptops and 802.11/Wi-Fi wireless networking have made MANETs a popular research topic since the mid 1990s. Many academic papers evaluate protocols and their abilities, assuming varying degrees of mobility within a bounded space, usually with all nodes within a few hops of each other. Different protocols are then evaluated based on measure such as the packet drop rate, the overhead introduced by the routing protocol, end-to-end packet delays, network throughput etc.

WMN: Wireless Mesh Networks

Wireless Mesh networks is becoming a major paradigm for constructing user access networks that provide community or city-wide Internet connectivity. The network coding, as a new technique which intermediate nodes in the network not only forward but also process the incoming information flows, will have a good application in wireless Mesh networks. Firstly, comparing traditional routing and network coding under unicast introduce the basic idea of network coding.

WSN: Wireless Sensor Networks

Recent advances in micro-electro-mechanical systems (MEMS) technology, wireless communications, and digital electronics have enabled the development of low-cost, low-power, multifunctional sensor nodes that are small in size and communicate untethered in short distances. These tiny sensor nodes, which consist of sensing, data processing, and communicating components, leverage the idea of sensor networks based on collaborative effort of a large number of nodes. Sensor networks represent a significant improvement over traditional sensors, which are deployed in the following two ways:

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  Sensors can be positioned far from the actual phenomenon, i.e., something known by sense perception. In this approach, large sensors that use some complex techniques to distinguish the targets from environmental noise are required.

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  Several sensors that perform only sensing can be deployed. The positions of the sensors and communications topology are carefully engineered. They transmit time series of the sensed phenomenon to the central nodes where computations are performed and data are fused.