Understanding Network Delay Measurements At Application Layers

As an emerging technology, Internet has an unprecedented development in recent decades in terms of numbers of users, network size and application function. New technologies are changing people's daily life incessantly such as E-commerce, Social Networking Services (SNS), cloud computing, Internet of things, microblog, etc. As network is more and more complex and users focus more on Quality of Service (QoS), researches on internal running conditions of network become very important. Network measurement has always been a hotspot of theoretical research as a means of understanding Internet. Delay measurement is an important branch in network measurement via which we can know the delay condition of network links so as to take series of measures such as conducting congestion control, link selection, server optimization deployment, etc. to shorten the service response time and improve network service.This paper focuses on the measurement of end-to-end link delay, it mainly includes three parts:1. It studies three measurement methods of typical application layers intensively which are respectively King, JavaScript and Flash, analyses the measuring principles of these three methods systematically and analyses them qualitatively in terms of accuracy, extensibility, measuring overhead, actual deployment and security. Then it shows the results and reveals the three measurement methods of typical application layers roundly;2. It develops a delay measurement platform based on web pages with Java language which provides convenient and swift services and favorable user interfaces and applies to large-scale measurements, meanwhile it implements the four measuring methods which are respectively King, JavaScript, Flash and Ping, and incorporates them into the platform which needs to design a logical database to store measuring datum;3. It measures the three measuring methods of King, JavaScript and Flash under two different circumstances of Local Area Network (LAN) and Wide Area Network (WAN) via the delay measurement platform. Through analyzing the measuring results from the database, the paper makes quantitative conclusions on accuracy and stability of the three methods, and studies their inaccuracy conditions through practical measurement and illustrates the reason causing the inaccuracy.