Comparative Analysis of Municipal Powers in Karachi

This study aims to draw a comparative analysis of the powers of local governments in Karachi. The subject of local government structure and its authority has become more important in the current local scenario. The findings of the study reveal that in past successive civilian governments in Pakistan did not pay attention to developing a solid local government system and instead preferred controlling districts and tehsils through the bureaucracy, with the absence of democracy and accountability at the local level. Instead of using this third tier of the government for the delivery of swift and better municipal services, they always made an effort to keep them weakened through legislation at different levels. The situation has now got worst in the biggest city and economic hub of Pakistan where people are deprived of basic facilities due to a handicapped system. The Mayor of the biggest city of Pakistan felt powerless as the provincial government through the Sindh Local Government Act 2013 deprived the Karachi Metropolitan Corporation of its main functions. The local bodies will have to be given the authority and essential powers. Only then these institutions can be made capable of providing basic services to the people.

Performance Optimization and Traffic Management in Data Centers

In recent years, Web services and applications are gradually shifting into cloud environments. These ever-increasing cloud services are being hosted on large scale computation and storage infrastructures called data centers (DC). A data center contains a large number of servers interconnected by a specifically designed network, named data center network (DCN). Today’s data centers host a variety of different applications that exhibit unique traffic characteristics. Some applications exhibit many-to-one communication pattern, some others follow ON-OFF pattern for flow arrivals resulting in bursty traffic. The many-to-one communication is a frequent pattern in data centers and may cause buffer overflow at the bottleneck link which ultimately results in throughput degradation of the flows; this problem is known as TCP Incast. In addition, data centers exhibit heavy tailed distribution for flow sizes; more than 80% of the data center flows have size less than 10 KB, called short flows, but around 90% of the traffic volume, in data center networks, is produced by long flows. Short flows are usually latency-sensitive and long flows demand high throughput. Short flows suffer to quickly increase their sending rates due to the existing long flows occupying most of the available capacity; this results in inefficient flow completion time (FCT) of short flows which ultimately results in degradation of the application’s performance. Furthermore, data centers employ scale-out model for growth to keep up with the rapid increase in the cloud services; thus, multiple paths exist between each pair of end-hosts. Load balancing of the traffic over the multiple path is required to improve network utilization. In addition, requirements like: i) high performance for applications, ii) scalability, and iii) robustness against topology changes, makes the load balancing task more challenging. This research thesis proposes queue length based solutions to the performance issues of TCP Incast and flow completion time of short flows. In addition, a queue length based traffic load balancing scheme is proposed to improve network utilization and applications’ performance. The proposed solutions are validated through implementation in network simulator and compared with the existing schemes. The results show that the proposed solutions significantly improve the performance of applications in the data centers.