Mobile ad hoc network researchers face the challenge of achieving full functionality with good performance while linking the new technology to the rest of the Internet. A strict layered design is not flexible enough to cope with the dynamics of manet environments, however, and will prevent performance optimizations. The MobileMan cross-layer architecture offers an alternative to the pure layered approach that promotes stricter local interaction among protocols in a manet node

One of the major challenges in the use of Radio Frequency-based Identification (RFID) on a large scale is the ability to read a large number of tags quickly. Central to solving this problem is resolving collisions that occur when multiple tags reply to the query of a reader. To this purpose, several MAC protocols for passive RFID systems have been proposed. These typically build on traditional MAC schemes, such as aloha and tree-based protocols. In this paper, we propose a new performance metric by which to judge these anticollision protocols: time system efficiency. This metric provides a direct measure of the time taken to read a group of tags. We then evaluate a set of well-known RFID MAC protocols in light of this metric. Based on the insights gained, we propose a new anticollision protocol, and show that it significantly outperforms previously proposed mechanisms

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The infra-structureless nature of ad hoc networks requires the distribution of network functions to all the participating nodes. The underlying requirement for making operational the cooperative paradigm is the supposed good behavior of all entities composing and, at the same time, using the system. However the lack of any centralized authority that enforces the overall collaboration motivates a possible tendency of entities toward self-interested behavior. In this paper we explore the cooperation issues across layers of the protocol stack for a network node. In particular, we perform a per-protocol analysis of cooperative aspects, and identify the problems potentially affecting each layer Afterward, we survey current research approaches to cooperation enforcing, highlighting common features among different layers' solutions, as well as open issues

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