ABSTRACT
On-demand routing protocols use route caches to make routing decisions. Due to mobility, cached routes easily become stale. To address the cache staleness issue, prior work in DSR used heuristics with ad hoc parameters to predict the lifetime of a link or a route. However, heuristics cannot accurately estimate timeouts because topology changes are unpredictable. In this paper, we propose proactively disseminating the broken link information to the nodes that have that link in their caches. We define a new cache structure called a cache table and present a distributed cache update algorithm. Each node maintains in its cache table the information necessary for cache updates. When a link failure is detected, the algorithm notifies all reachable nodes that have cached the link in a distributed manner. The algorithm does not use any ad hoc parameters, thus making route caches fully adaptive to topology changes. We show that the algorithm outperforms DSR with path caches and with Link-MaxLife, an adaptive timeout mechanism for link caches. We conclude that proactive cache updating is key to the adaptation of on-demand routing protocols to mobility
TABLE OF CONTENTS
TITLE PAGE
CERTIFICATION
DEDICATION
ACKNOWLEDGEMENT
ORGANIZATION OF WORK
ABSTRACT
TABLE OF CONTENT
CHAPTER ONE
1.0 INTRODUCTION
1.1 STATEMENT OF THE PROBLEM
1.2 PURPOSE OF THE STUDY
1.3 AIM AND OBJECTIVES
1.4 SCOPE OF STUDY
1.5 CONSTRAINTS
1.6 ASSUMPTION
1.7 DEFINITION OF TERMS
CHAPTER TWO
2.0 LITERATURE REVIEW
CHAPTER THREE
3.0 DESCRIPTION AND ANALYSIS OF THE EXISTING SYSTEM
3.1 FACT FINDING METHODS USED
3.11 REFERENCES TO WRITTEN DOCUMENT
3.1.2 BROWSING OF INTERNET
3.2 INPUT, PROCESS, OUTPUT ANALYSIS
3.2.1 INPUT, ANALYSIS
3.2.2 INPUT FORMAT
3.2.3 PROCESS, ANALYSIS
3.2.4 OUTPUT, ANALYSIS
3.2.5 INPUT FORMAT
3.3 PROBLEM OF THE EXISTING SYSTEM
3.4 OBJECTIVE OF THE EXISTING SYSTEM
3.5 JUSTIFICATION OF THE NEW EXISTING SYSTEM
CHAPTER FOUR
4.0 THE DESIGN OF THE NEW SYSTEM
4.1 OUTPUT SPECIFICATION AND DESIGN
4.2 INPUT SPECIFICATION AND DESIGN
4.3 FILE DESIGN
4.4 FILE STRUCTURE
4.5 PROCEDURE CHART
4.6 SYSTEM FLOWCHART
4.7 SYSTEM REQUIREMENT
4.71 HARDWARE REQUIREMENT
4.72 SOFT WARE REQUIREMENT
5.0 IMPLEMENTATION
5.1 PROGRAM DESIGN
5.2 PSEUDO CODE
5.3 PROGRAM FLOWCHART
6.0 DOCUMENTATION
6.1 CHOICE OF LANGUAGE
6.2 LANGUAGE INTRODUCTION
6.3 CHANGE OVER METHOD
7.0 CHAPTER FIVE
8.0 CONCLUSION
7.1 RECOMMENDATION
BIBLIOGRAPHY
