What "in-house application"means ? Problem with translating

Question

I have problem with translating this sentence:

"Running in-house systems means that you can leverage your existing security system for purposes of authentication, authorization, and so forth" - from Pro C# 2010 and the .NET 4 Platform

Google translate doesn't help me with this.

I don't want to translate it to my language, but I want explanation, the best with some examples.

Answer 1

In-House systems means applications that have been written internally in a company.

Answer 2

I think it means that if you build your own system as opposed to purchasing something, you can integrate your own login process (use single sign-on).

For example, if you purchase XYZ and WidgetCo, you have to have a separate login for each application. If you build your own, you can reference AD or whatever your login process is.

Answer 3

Software written and used within the same company.