> For the complete documentation index, see [llms.txt](https://dgtnetwork.gitbook.io/dgt-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dgtnetwork.gitbook.io/dgt-docs/3.-dgt-architecture/3.1-scalable-architecture-design/3.1.1-high-level-architecture.md).

# 3.1.1 High Level Architecture

The reference architecture involves the description of the most important decisions and components of the corresponding software system. The DGT platform supports standardized cryptography, networking, and data storage components that correlate with the most important published models of distributed architectures, primarily [ITU-T Technical Specification FG DLT D3.1 Distributed ledger technology reference architecture](https://www.itu.int/en/ITU-T/focusgroups/dlt/Documents/d31.pdf), 2019 and ISO 23257 Blockchain and distributed ledger technologies — Reference architecture. By these principles, the architecture of distributed systems can be represented by basic layers:

![Figure 6 ITU-T High-level conceptual architecture of DLT (ITU-T, 2019)](https://3210145376-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FSvanFNAf6Jf8kwvqcdRQ%2Fuploads%2FPmJtAoveJHBD0JQSlYdq%2F0.png?alt=media)

Within the system architecture, [DGT ](#user-content-fn-1)[^1]delineates horizontal layers, which correspond to the classical architecture of complex information systems. On the other hand, vertical partitioning highlights the user view (tiers). The FIRST TIER is the platform itself, the DGT CORE. The SECOND TIER is the extension of functionality. The DAPPs tier is for end applications. Together the last two form the DGT GARANASKA subsystem.

![Figure 7 System View of DGT Architecture](https://3210145376-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FSvanFNAf6Jf8kwvqcdRQ%2Fuploads%2FSG3dhVqDvO9Rzn1VeRWt%2F1.png?alt=media)

[^1]: At its core, the DGT software is a node containing many components and services. Node components are discussed in [3.3.8](/dgt-docs/3.-dgt-architecture/3.3-network-architecture/3.3.8-node-networking.md)