system testing and alpha testing
System test is done on a fully integrated system and is done at developers site by the testers team.
Acceptance test is of two types : alpha and beta
alpha is done at developers site and by the persons within the software developing organization.
while beta is performed by end users and at users site, not at the developers site.
My question is if both system and alpha testing is performed at developers site and is performed by persons within the organization then what is difference between the two???
I think your understanding of these testing types is a little skewed.
A system test is done within the system itself; and NOT at a developers sandbox. Tests at a developer machine are typically unit tests.
For acceptance testing, that is usually when you put your product in front of a focus group to get their feedback and see if it meets requirements. The terms 'alpha' and 'beta' are used to denote the place your project is in within the SDLC.
The difference between the two is that system testing can be done regardless of your product being in an alpha or beta state.