Resumen
The problem of integration of heterogeneous information systems is relevant in connection with creation of a common information space in digital economy. In the world an experience of creation and operation of such systems is accumulated.In article the analysis of some examples for the purpose of identification of the problems arising at operation and development of information systems of the state level is carried out. The research relies on experience of the Netherlands and Estonia.Integration of information space in Netherlands is based on uniform technical standards and standards of message exchange. Language of data view, based on message exchange, is rather "rich" to express new data, new requests, and, thereby, to develop information space. However, this language creates problems on the party of the message recipient. Namely, extraction of the different formats given from messages is a complex problem. It is connected with assessment of correctness of identification of required data and also with assessment of completeness data, which were received from different messages.Coordination of languages and the message formats results in need of creation of integration buses, which are more or less simple at "poor" languages of communication, i.e. all communication should keep within simple templates. Experience of Estonia is based on use of "poor" languages.Usage of "poor" languages creates new problems at upgrade of heterogeneous information systems. For expansion of languages of communication in "poor" languages often begin to use semantic approaches and intelligent data analysis. An essential role at integration of heterogeneous distributed systems is played by a problem of information security. It is connected with the fact that the decentralized system generates a set of different security policies for which their union is not always possible because of their inconsistency.