As the number of mobile devices accessing large-scale WLANs such as campus
and metropolitan area networks increases, the need for load balancing among the
cells becomes crucial. In addition, the network must also support some minimum
handoff tolerance defined by an application.
A number of load balancing techniques have been...
NAND flash based solid state drives (SSDs) require out-of-place updating due to the characteristics of flash memories. In addition, due to the mismatched granularity between read/write and erase operations, a cleaning policy involving garbage collection and wear leveling has to perform data migration incurring high overhead. Another challenge is that...
The ubiquity of high quality video and proliferation of mobile devices has contributed to an unprecedented rise in video consumption. HTTP, in conjunction with adaptive streaming, has become the de facto mechanism for delivering the vast majority of video as it readily caters to heterogeneous networks and devices. This dissertation...
Traditional approaches to streaming H.264 video over a network typically rely on a single method of transport (i.e., reliable or unreliable) and/or use static values for parameters that can have a significant negative impact on the perceptual quality of the received video. This dissertation presents a dynamic method for wireless...
A Mobile Ad-hoc NETwork (MANET) is collection of wireless mobile nodes without a network infrastructure or centralized administration. Although MANETs can be used in many applications, such as mobile Internet, military communication, and disaster relief networks, a number of challenges remain. These include routing, medium access control, security, scalability, energy...
High Definition video streaming over WLANs faces many challenges because video data requires not only data integrity but also frames have strict playout deadline. Traditional streaming methods that rely solely on either UDP or TCP have difficulties meeting both requirements because UDP incurs packet loss while TCP incurs delay. This...
Flexible Dual-TCP/UDP Streaming Protocol with Adaptive Bitstream Prioritization (FDSP with Adaptive-BP) is a new method for streaming H.264-encoded High-definition (HD) video over WLANs. Traditionally, video streaming is done either using Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) protocol, resulting in either rebuffering or packet loss respectively. While FDSP-based...
Wireless High Definition Video Transmission (WHDVT) over 802.11-based networks enjoys widespread deployment among today's multimedia solutions. Examples include Intel® Wireless Display and Apple Airplay®, to name a few. In these systems, peer-to-peer networks are established over which H.264-encoded video is transported wirelessly to be decoded and played back at the...
MANETs are known to be useful in situations where mobile nodes need to communicate and coordinate in dynamic environments with no access to fixed network infrastructure. However, connectivity problems can occur when sub-groups within a MANET move out of communication range from one another. The increasingly prolific use of UAVs...
As the performance gap between processor and memory grows, memory latency will be a major bottleneck in achieving high processor utilization. Multithreading has emerged as one of the most promising and exciting techniques used to tolerate memory latency by exploiting thread-level parallelism. The question however remains as to how effective...
The AE32000 processor core, developed by Advanced Digital Chips Inc., Korea, is used primarily in the embedded processing environment. The AE32000 simulator models this embedded processor core having high code density. An enhanced simulator was developed to study the performance of the present Instruction Set Architecture after comparison with the...
Efficient routing of messages is critical to the performance of multicomputers. Many adaptive routing algorithms have been proposed to improve the network efficiency; however, they can make only short-sighted decisions to choose a channel for message routing because of limited information about network condition. The short-sighted decisions may cause unnecessary...
Mobile devices are becoming more prevalent and complex. As a result, the wireless communication aspect of these devices is becoming increasingly significant. At the same time, video demands in terms of availability and quality are also on the uprise. High definition (HD) video is the standard of choice for meeting...
AE32000 microprocessor was developed mainly to address the need for the reduction in the amount of memory accesses in embedded applications. One of the primary goals of a computer architect is the design and construction of machines, that support the efficient execution of the programs that will run on them....
Rapid advances in wireless networking have led to more mobile phones, PDAs, and other digital mobile devices becoming ubiquitously connected to the Internet. As the demand of delay sensitive real-time applications for these portable devices increases, providing seamless connectivity to wireless networks becomes a critical issue. For this reason, a...
As screen resolution and video decoding capability have increased, high-definition (HD) video in resolutions as high as 1920 x 1080 is rapidly becoming the standard. Ad-hoc streaming of HD video over 802.11 wireless networks, e.g., streaming from a mobile device to a television, is convenient for users, but is hampered...
The purpose of this thesis is to explore methods which can reduce the power dissipation of a mobile system while decoding MPEG video. MPEG decoding is a microprocessor intensive process that makes heavy use of both the L1 and L2 caches as well as main memory. The heavy load placed...
General purpose computer systems have seen increased performance potential through the parallel processing capabilities of multicore processors. Yet this potential performance can only be attained through parallel applications, thus forcing software developers to rethink how everyday applications are designed. The most readily form of Thread Level Parallelism (TLP) within any...
Wireless Networks have been widely adopted into a major part of today's network infrastructure. They have become a popular technology to not only expand the coverage of wired networks but also to interconnect a large wireless network, i.e., wireless mesh networks. As they allow more flexible communication than traditional wired-networks...
The Advent of multi-cores allows programs to be executed much faster than before. Cryptoalgorithms use long-bit words thus parallelizing these operations on multi-cores will achieve significant performance improvement. However, not all long-bit word operations in cryptosystems are suitable for parallel execution on multi-cores. In particular, long-bit words used in Elliptic...