I'll tell you my experience:
1) System architect (SA in the future) rise of the programmers or system analysts.
2) the System architect is the person who monitors the overall system architecture (surprisingly!) and is responsible for the product or a highlighted block of functionality in General, which implies the understanding of the structure component, all integration, all objects and their attributes, business rules, and so on. Being SA, people should (ideally) answer any questions on where and what to look for in the product, how it works and architectural and how to interact with it - any questions on how to integrate, give feedback BA on their ideas of product development, have the skills to add functionality to the product without disturbing its operation.
2) Requirements for knowledge similar to the requirements for the experienced programmer:
. Programming languages - depending on jobs, like bacovia and the front;
b. Definitely a good knowledge and understanding of development, database (SQL conceived it);
V. Good understanding of software development process in General - a key role, the sequence of development from backlog to completion of testing, etc Understanding and canine key methodologies - Agile, Waterfall.
g. Knowledge of notations UML, IDEF BPMNб.
D. In some cases it is a good knowledge of corporate software (Sady, CRMы, ERP, etc.).
And much more, depending on the specific needs of the employer.
3) SA post-paid, but has a fairly high requirements. If you want to become a CA and there is a misunderstanding of his duties - clearly you before, start with a business analyst or programmer. If you want to hire or open to this vacancy - we need more specifics to answer thoroughly.