Design and analysis of multi-path routing.

Ma Ke.Thesis (M.Phil.)--Chinese University of Hong Kong, 2003.Includes bibliographical references (leaves 64-68).Abstracts in English and Chinese.Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Background --- p.1Chapter 1.2 --- Motivation --- p.2Chapter 1.3 --- Contribution --- p.3Chapter 1.4 --- Organization --- p.4Chapter 2 --- Literature Review --- p.5Chapter 2.1 --- Overview --- p.5Chapter 2.2 --- Multi-Path Routing --- p.6Chapter 2.2.1 --- OSPF-ECMP --- p.7Chapter 2.2.2 --- LFI --- p.7Chapter 2.2.3 --- QSMP and QDMP --- p.9Chapter 2.2.4 --- WDP --- p.10Chapter 2.2.5 --- DMPR --- p.11Chapter 2.2.6 --- Cidon's Analysis --- p.13Chapter 3 --- LSLF and SLSLF Conditions --- p.15Chapter 3.1 --- Problem Formulation --- p.15Chapter 3.2 --- LFI Conditions --- p.16Chapter 3.3 --- LSLF Conditions --- p.17Chapter 3.4 --- SLSLF Conditions --- p.20Chapter 4 --- Performance of LSLF and SLSLF --- p.24Chapter 4.1 --- Overview --- p.24Chapter 4.2 --- Numerical Results --- p.26Chapter 5 --- Analysis of Multi-path Routing --- p.42Chapter 5.1 --- Assumptions --- p.43Chapter 5.2 --- M/M/C/C Queueing System --- p.44Chapter 5.3 --- Performance Analysis --- p.48Chapter 5.3.1 --- "Case 1 Only QoS flows between (s, d) exist" --- p.48Chapter 5.3.2 --- Case 2 QoS flows between other SD pairs also exist --- p.50Chapter 5.3.3 --- Case 3 A QoS flow can try m times before it is dropped --- p.53Chapter 5.4 --- Numerical Results --- p.56Chapter 6 --- Conclusion --- p.6

Making On-Demand Routing Efficient with Route-Request Aggregation

In theory, on-demand routing is very attractive for mobile ad hoc networks (MANET), because it induces signaling only for those destinations for which there is data traffic. However, in practice, the signaling overhead of existing on-demand routing protocols becomes excessive as the rate of topology changes increases due to mobility or other causes. We introduce the first on-demand routing approach that eliminates the main limitation of on-demand routing by aggregating route requests (RREQ) for the same destinations. The approach can be applied to any existing on-demand routing protocol, and we introduce the Ad-hoc Demand-Aggregated Routing with Adaptation (ADARA) as an example of how RREQ aggregation can be used. ADARA is compared to AODV and OLSR using discrete-event simulations, and the results show that aggregating RREQs can make on-demand routing more efficient than existing proactive or on-demand routing protocols

Design of a main/sub dual-channel LED driver

针对传统的矿灯存在的体积大、寿命短、耗电量大、玻璃易碎、使用不安全等不足,设计了一款以锂电池为电源、LED为光源、高精度欠压阈值和主辅双通道自动切换的恒流驱动芯片,减小了矿灯的体积和重量,提高了矿灯的寿命和安全使用性能。为了既保证主灯的生产工作时间,又保证辅灯的应急时间,提出一种高精度欠压阈值检测电池电压,实现双通道自动切换的结构,精确检测电池的容量变化,保证了充电的时间节点,确保了矿灯使用安全;为解决电池电压充电节点的一致性,设计了时序逻辑校正控制结构电路,精确调整了分压电阻的阻值,实现了带有80 m V迟滞的欠压阈值±2%电压范围的控制,有效防止了因电源波动引起双通道切换的误操作,满足芯片稳定性好、抗干扰性强的设计要求。另外还设计了主灯短路保护和过温保护等电路,进一步保证矿灯工作安全。Safety is the most important factor in miner production,and there are a lot of accidents are caused by miner's lamp. Traditional miner's lamps use lead-acid batteries for power,incandescent tungsten as light source which has a number of disadvantages such as large volume,high maintenance costs,short lifetime,great power consumption and unsafely because of the fragile glass. This paper designed a lithium battery as the power supply,the LED as light source of high precision under voltage threshold and automatic switching dual channel driver with constant current,overcome the above disadvantages.This paper presents a structure that the dual channel can switch automatically by detecting the battery voltage with high precision under voltage threshold to ensure working time of the main light production and emergency time of auxiliary lights. Accurate detection of changes in battery capacity guarantees that the right charging time and improves the safety of the lamp. To charge battery consistently,it designs a sequential logic circuit,making under voltage threshold voltage in the range of ± 2% with 80 m V hysteresis for high precision requirement. In order to reduce the power dissipation,it designs a 8000-fold high-gain current amplifier to drive linear MOS with 0. 1 V dropout for 200 m A. The chip provides the main LED shorts protection and over temperature protection against unexpected situations

Study and Analysis of Ant System

Alot of species of ants have a trail-laying/trailfollowing behavior when foraging. While moving, individual ants deposit on the ground a volatile chemical substance called pheromone, forming in this way pheromone trails. Ants can smell pheromone and, when choosing their way, they tend to choose, in probability, the paths marked by stronger pheromone concentrations. In this way they create a sort of attractive potential field, the pheromone trails allows the ants to find their way back to food sources (or to the nest). Also, they can be used by other ants to find the location of the food sources discovered by their nest mates

Optimizing the Dynamic Distribution of Data-stream for High Speed Communications

The performances of high-speed network communications frequently rest with the distribution of data-stream. In this paper, a dynamic data-stream balancing architecture based on link information is introduced and discussed firstly. Then the algorithms for simultaneously acquiring the passing nodes and links of a path between any two source-destination nodes rapidly, as well as a dynamic data-stream distribution planning are proposed. Some related topics such as data fragment disposal, fair service, etc. are further studied and discussed. Besides, the performance and efficiency of proposed algorithms, especially for fair service and convergence, are evaluated through a demonstration with regard to the rate of bandwidth utilization. Hoping the discussion presented here can be helpful to application developers in selecting an effective strategy for planning the distribution of data-stream.Singapore-MIT Alliance (SMA

Study of Routing Protocols in Telecommunication Networks

In this paper we have discussed the problem of routing in telecommunication networks and the salient characteristics of some of the most popular routing schemes. In particular, we have discussed the characteristics of adaptive and multipath routing solutions versus static and single-path strategies

Multipath routing for video delivery over bandwidth-limited networks

The delivery of quality video service often requires high bandwidth with low delay or cost in network transmission. Current routing protocols such as those used in the Internet are mainly based on the single-path approach (e.g., the shortest-path routing). This approach cannot meet the end-to-end bandwidth requirement when the video is streamed over bandwidth-limited networks. In order to overcome this limitation, we propose multipath routing, where the video takes multiple paths to reach its destination(s), thereby increasing the aggregate throughput. We consider both unicast (point-to-point) and multicast scenarios. For unicast, we present an efficient multipath heuristic (of complexity O(|V|3)), which achieves high bandwidth with low delay. Given a set of path lengths, we then present and prove a simple data scheduling algorithm as implemented at the server, which achieves the theoretical minimum end-to-end delay. For a network with unit-capacity links, the algorithm, when combined with disjoint-path routing, offers an exact and efficient solution to meet a bandwidth requirement with minimum delay. For multicast, we study the construction of multiple trees for layered video to satisfy the user bandwidth requirements. We propose two efficient heuristics on how such trees can be constructed so as to minimize the cost of their aggregation subject to a delay constraint.published_or_final_versio