## 8 Conclusions and Future Work  
In this paper, we have designed a new rooting protocol for MANETs to send video-warning messages in a smart city. The routing protocol is based on a game-theoretical scheme for \(N\) users. Our framework could be used in smart cities where prevention of accidents is an important goal. We understand that with a video message, the level of seriousness of the accident could be much better evaluated by the authorities allowing a fast warning of the incident to emergency units, which potentially could save lives. The users of the framework could be any dynamic sensor such as citizens with smart phones or tablets that could participate in the MANET to send the video to the competent authorities. Also, smart citizens would easily be warned by other citizens about any situation in the city, which would improve the quality of life in the smart cities. In our framework, the probability \(p\) of sending the most important video frames (_i.e._, I+P frames) through the best available path varies depending on some network characteristics. This way, instead of sending the I+P video frames always through the best available path, users play a strategic routing game where these frames will be sent through one of the two best paths according to a certain probability \(p^{*}\). Simulation results in the MANET scenario show the benefits of our proposal by outperforming the results compared to the case of non using our game-theoretical routing. In terms of packets losses, delay and jitter, results notably improve for \(N\) = 2, 3, 4 and 5 users, due to the new way of selecting the forwarding path based on \(p^{*}\). Our proposal makes the network more efficient as well as achieves \begin{table}
\begin{tabular}{c c} \hline
**Map Zone** & **Example District of Barcelona** \\ \hline Area & 850 \(\times\) 580 m\({}^{2}\) \\ Number of nodes & 50 \\ Transmission range & 120 m \\ Mobility generator & SUMO [39]/C4R [38] \\ MAC specification & IEEE 802.11p \\ Nominal bandwidth & 11 Mbps \\ Simulation time & 250 s \\ Video encoding & MPEG-2 VBR \\ Video bit rate & 150 Kbps \\ Video sources & 2 \\ Video sequence sent & Traffic accidents [37] \\ Routing protocol & Game-theoretical algorithm + MMDSR \\ Transport protocol & RTP/RTCP/UDP \\ Maximum packet size & 1500 Bytes \\ Multipath scheme & \(K\) = 3 paths \\ Weighting values (Equation (3)) & 1/7 \\ Queue sizes & 50 packets \\ Interfering CBR traffic & 100 Kbps \\ \hline \end{tabular}
\end{table} 
Table 6: Simulation settings of the VANET scenario. a higher degree of satisfaction of the users by receiving much more (I+P) frames with a lower average end-to-end delay and jitter. This definitively will improve the quality of the video perceived by the end user. Moreover, improvements are also shown for \(N\) = 2 users in the simulation results of a VANET scenario, in terms of percentage of packet losses, average packet delay and average delay jitter. As a future work, we are planning a further contribution with a multi-user game-theoretical forwarding algorithm included in the operation of a geographical routing protocol specially designed to distribute multimedia data over VANETs in smart cities. In this kind of scenarios, video-streaming services are taking an important attention from the interest to distribute light and short videos to allow drivers, passengers, paramedics, and first responder teams to capture, share, and watch video sequences from accidents and other emergencies that happened in the city. This way, multimedia warning messages sent upon the event of a traffic accident will allow the emergency units to make a better preliminary evaluation of the situation. Our proposal could be a solution to improve the routing operation to distribute multimedia data over VANETs in smart cities. In addition, as a future work, the weights of the QoS metrics will be self-configured.