aussiejohnEvery organisation is different, even within one industry group such as IT. None of these things is a one size fits all proposition. So much depends on just what the raison d'etre of the organisation is. An IT software company is different from an IT hardware company etc, etc.
The organisational structure of YOUR organisation should have already been formulated and stated in the business plan when the organisation was set up. Either find a copy of the business plan or speak to the company directors and ask them for this information.
From Australia, Melbourne