Interoperability Protocol of Digital Libraries Systems

[[abstract]]In the information environment with diverse heterogeneity, users are burdened with the problem to find appropriate resources. Because of the rage of researches and implementations in digital library, every institution invests a lot of money in digitizing their collections or in purchasing digital resources for users. However, different vendors have their own closed interfaces to support their services and may provide the same content. Thus, to develop integrated search systems becomes an important issue to make the best use of digital resources. This paper focuses on two protocols of interoperability: OAI and OpenURL. We explain their designs and, how they work . We also indicate their differences. Besides, the unique identifier to digital resources is another key issue. Therefore, we analyze the schemes of digital resources, and explain how DOI works with CrossRef, OpenURL, and SFX.