Smartphone-based crowdsourcing for estimating the bottleneck capacity in wireless networks

Crowdsourcing enables the fine-grained characterization and performance evaluation of today׳s large-scale networks using the power of the masses and distributed intelligence. This paper presents SmartProbe, a system that assesses the bottleneck capacity of Internet paths using smartphones, from a mobile crowdsourcing perspective. With SmartProbe measurement activities are more bandwidth efficient compared to similar systems, and a larger number of users can be supported. An application based on SmartProbe is also presented: georeferenced measurements are mapped and used to compare the performance of mobile broadband operators in wide areas. Results from one year of operation are included

Monitoring Access Link Capacity Using TFRC Probe

[[sponsorship]]資訊科學研究所,資訊科技創新研究中心[[note]]已出版;[SCI];有審查制度;具代表性[[note]]http://gateway.isiknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Drexel&SrcApp=hagerty_opac&KeyRecord=0140-3664&DestApp=JCR&RQ=IF_CAT_BOXPLO

Monitoring Access Link Capacity Using TFRC Probe

this paper, we will discuss a passive link capacity estimation technique by embedding CapProbe techniques within TFRC protocol. The details of the design and protocol integration will be presented in the following subsections, and the evaluation of the proposed integration will be discussed in the simulation and experiments section

Monitoring Access Link Capacity Using TFRC Probe ∗

Accurate estimation of network characteristics based on end to end measurements is an important and challenging problem. With the increasing variety and sophistication of Internet access methods, the mobility of the users and the need for seamless handoff across them, monitoring access link capacity becomes critical for efficient multimedia delivery. In fact, this allows the multimedia server to properly adjust its sending rate to the rapidly changing access speed of the mobile client. This problem is challenging because most of the existing capacity monitoring schemes are active, like Pathrate (and therefore introduce extra overhead on the bandwidth limited access link). Moreover, the access link is often asymmetric (eg, ADSL, 1xRTT, etc) thus preventing the use of round trip monitoring schemes such as Pathchar and CapProbe. In this study, we propose and evaluate a passive, one-way link capacity monitoring tool called TFRC Probe. With TFRC Probe the source can monitor the forward direction capacity of both asymmetric and symmetric access links, and can rapidly and accurately adapt its transmissions rate accordingly. We validate TFRC Probe with both simulation and testbed experiments, and show that TFRC Probe is a very flexible tool that can accurately track frequent changes in access capacity. Keywords: Passive capacity estimation; TFRC Probe; CapProbe. 1