Documents have DOI numbers. doi refers to digital object unique identifier, is the best "big data" sample storage and application technology in the context of cloud computing, used for IKE for negotiation of SA protocol uniform distribution.

The steps are as follows:

1, open the ZhiNET, in the search box, enter the keywords of the article you want to search, and then click search;

2, in the search page click on the title of the paper, to open a Chinese paper;

3, you can see the paper's relevant information in the paper's page, click on the arrow pointing to the HTML to read the figure, or you can choose to the paper will be download it down.

4, the top is the DOI number of this paper, generally the DOI number of the paper will be displayed on the first page.