Аннотация:In this paper, we discuss cyber-security issues for a digital economy. In particular, this paper targets the complexity of software development for information systems and related problems. This article provides the review of development-related problems for the biggest information systems in the world. We discuss Global Services Management-Operations, DISN, MFSS, and JRSS. This article concentrates on the creation (description) of the system architecture. In our opinion, this is the main issue for large systems. In this connection, the paper discusses the concept of “enterprise architecture” and the framework (model) for Information Systems Architecture proposed by A. Zachman. The main idea of the model is to provide the possibility of the sequential description of each individual aspect of the system in coordination with all the others. Also, we discuss DoDAF metamodel. Any model of enterprise architectures should cover, of course, cyber-security aspects.