200 mph in neutral - Cloud-testing compared to traditional testing with-in the corporate LAN
The following is an article on load testing by Alon Girmonsky.
"Web site performance testing while simulating a load scenario where the actual traffic originates from with-in the corporate Local Area Network can be compared to testing a car's performance when it is actually situated on the garage's lift. You floor the gas paddle, go into fifth gear and easily enjoy 200 mph.
Only the car is still on the lift and in fact not moving ...
There is no friction on the road, no cars you need to bypass, no traffic lights, no narrow lanes .. simply ideal conditions.
This how it goes when you test from with-in the corporate LAN. You do not go through the firewall, nor through the cache, the load balancer, the network equipment, the modem, the routers along the way. No collisions of packets or re-transmits.
In the real world there are numerous factors that affect your website performance in a load scenario. These are not included while testing with-in the corporate LAN. Testing from with-in the corporate LAN indeed contributes as it does test the functionality of your website even under load, but it certainly does not reflect the system performance under load, as it would happen in real-world load scenario.
Cloud-testing makes use of cloud-computing resources in order to simulate real users who come directly from the internet.
Why play "pretend" if you can simulate the real thing."
A very good article on load testing by Alon Girmonsky.