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In recent years, video streaming over wireless mesh networks (WMNs) has been of great interest among the users. In WMNs, although node mobility and scalability are the two most important well-known advantages by end-users, they can decrease the perceived video quality on receivers with increasing the probability of path failure, especially when the number of mobile mesh nodes and their mobility speeds increase. Therefore, the necessity of employing an efficient routing protocol to consider the effects of node mobility is inevitable. Moreover, the interference can be sharply increased, especially on the gateways, when there are many mobile mesh nodes in a WMN. Interference does not permit the system to support many STA and mobile mesh nodes. In order to cope with these challenges, this study introduces and evaluates a good hybrid routing protocol for data dissemination which efficiently and effectively routes packets in a wireless mesh network and intelligently employs proactive and reactive routing protocols based on the node mobility (GREENIE) for efficient video streaming over WMNs and extensively compares it with other routing protocols including hybrid wireless mesh protocol, proactive, reactive, and spanning trees using OMNET++ simulator. GREENIE intelligently distinguishes mobile from static nodes and selects the most stable path between a source and a destination which leads to higher perceived video quality on receivers. The results show the impact of GREENIE on the perceived video quality so that it considerably outperforms other routing protocols in terms of the total number of successfully received packets, the end-to-end delay, and the imposed routing overhead on the system. One of the main advantages of GREENIE is that it performs routing in the medium access control layer without applying any change in the functions of the internet protocol layer.

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In recent years, Random Network Coding (RNC) has emerged as a promising solution for efficient Peer-to-Peer (P2P) video multicasting over the Internet. This probably refers to this fact that RNC noticeably increases the error resiliency and throughput of the network. However, high transmission overhead arising from sending large coefficients vector as header has been the most important challenge of the RNC. Moreover, due to employing the Gauss-Jordan elimination method, considerable computational complexity can be imposed on peers in decoding the encoded blocks and checking linear dependency among the coefficients vectors. In order to address these challenges, this study introduces MATIN which is a random network coding based framework for efficient P2P video streaming. The MATIN includes a novel coefficients matrix generation method so that there is no linear dependency in the generated coefficients matrix. Using the proposed framework, each peer encapsulates one instead of n coefficients entries into the generated encoded packet which results in very low transmission overhead. It is also possible to obtain the inverted coefficients matrix using a bit number of simple arithmetic operations. In this regard, peers sustain very low computational complexities. As a result, the MATIN permits random network coding to be more efficient in P2P video streaming systems. The results obtained from simulation using OMNET++ show that it substantially outperforms the RNC which uses the Gauss-Jordan elimination method by providing better video quality on peers in terms of the four important performance metrics including video distortion, dependency distortion, End-to-End delay and Initial Startup delay.

This work describes how some of the most popular ad hoc routing protocols (DYMO, DSR, AODV) have been implemented for the INET library of OMNeT++ simulator tool. The developed modules have been programmed so they can be easily extensible to include future routing MANET protocols.

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A crucial aspect of quality of service routing is the frequency with which the nodes have to exchange information about the availability of network resources. The authors classify and compare several strategies for triggering the update process in the nodes. Simulating an actual wide area network as a test-bed, it is shown that the triggering must be based on the relative variations of the available bandwidth in the links, in contrast to using the utilised bandwidth or considering an absolute threshold or a policy of periodical updates.