In recent years, the use of Autonomous Underwater Vehicle (AUV) along a constrained path can improve the data delivery ratio and maximize the energy efficiency in Underwater Wireless Sensor Networks (UWSNs). However, constant speed of AUV leads to limited communication to collect data packet from nodes deployed randomly in large scalable network. Moreover, the excessive number of associated nodes with Gateway Node (GN) causes to quick depletion of its energy, thus lead to hot spot problem. This poses prominent challenges in jointly improving the throughput with minimum energy consumption. To address these issues, we presented a novel scalable data gathering scheme called Scalable and Efficient Data Gathering SEDG routing protocol, that increases the packet delivery ratio as well as conserves limited energy by optimal assignment of member nodes with GN. Moreover, the variable sojourn interval of AUV decreases the packet drop ratio and hence, maximize the throughput of network.

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Video traffic is a variable bit rates (VBR) data source in nature and it generates highly bursty traffic.Recent implementations mostly buffer the media source in order to regenerate it in the form of constant bit rates (CBR). Consequently, it will add more delays to the system and thus unable to support the original nature of the video data. Inspired by the works of Hamdi et al. [1] and Lie and Klaue [2], we developed Evalvid-RASV.This system is working on the VBR concept (open-loop video coding), but it is "shaped" so that it will not produce uncompromised bursty traffic without additional delay.With the knowledge of video characteristics in advance, Evalvid-RASV was developed to utilize the information resulting a better algorithm.In addition, we implemented the system in Evalvid-RA environment. It is an environment which is able to perform rate adaptation to the media data source and has an integrated video performance evaluation tools, especially user-perceived video quality. Our experiments have shown that Evalvid-RASV outperforms open-loop VBR in term Peak Signal Noise Ratio (PSNR) value and acceptable delay time.

Packet pacing in TCP has been introduced as one of the solutions to alleviate bursty traffic in TCP. In this paper, we investigate the performance of paced and standard (unpaced) TCP when coexist with DCCP over short and long delay link networks. We found that paced TCP for the entire TCP connection performs better in long delay link, with smoother throughput and better jitter, whereas in short delay link, there is not much positive effect of using pacing for TCP. The existence of DCCP together with TCP flows does not much affect the performance of paced TCP. However, the performance of paced TCP is slightly better when coexisting with DCCP TCP-like and DCCP TFRC in comparison to standard TCP. Based on the result, it can be used as a fundamental in implementing packet pacing in DCCP TCPlike.