Towards a Solution for the Public Web-Based GIS Monitoring and Alerting System - Geoinformatics for Intelligent Transportation - page 125

Fig. 3 Experimental system with thin client interface
3.3 Thick Client
Figure 4 shows the desktop client interface of our thick-client. It is implemented in
C#.Net Winforms. The desktop client application was extended to be a load testing
tool. As Websocket is a new protocol, there are no load testing tools that can act
over WebSocket and none extensible with some subprotocols. This client allows us
to do real benchmarks of Weda against REST and SOAP over HTTP SOS service.
Legacy SOAP/REST endpoints are also invoked and used in benchmarks as
baseline.
4 Performance Analysis
We measured response time instability of Weda by invoking number of requests
(according to SOS GetCapabilities, DescribeSensor, GetObservation and GetFea-
tureOfInterest operations) from the thick client application and collecting the
responses with metadata about server processing times and other parameters (such
as 20 kB amount of transferred data per request etc.).
The load generator was hosted on 4xIntel Xeon running at 2.5 Ghz, Windows 8,
2 GB of RAM, 1Mbps downlink network connection and 100 Kbps uplink network
connection. The location of the load generator was 4 network hops away from the
server hosting the service. Reverse proxy (no caching) was placed between the
client and server. The average packet round trip time was 33 ms and constituted less