The invention relates to a two-way data communication apparatus in television broadcast or data broadcast signal transmitted through telephone circuit, and a two-way data communication apparatus according to this method, and more particularly, in a system having a response server and an individual information...http://www.google.co.uk/patents/US5887062?utm_source=gb-gplus-sharePatent US5887062 - Two-way data communication method and two-way data communication apparatus using the same
