The network architecture is the conceptual framework for communication systems or for computers, in which the functions, interfaces and procedures are defined, how and in which form the individual network components communicate with each other.
As far as network architectures are concerned, there are open network architectures and proprietary, vendor-specific ones. The open architectures are specified by Open Systems Interconnection( OSI) and standardized by IEEE, and can be used by all companies worldwide if they comply with the specifications. The vendor-bound network architectures are based on vendor-specific, non-public standards and work with vendor products or licensed products. They generally originate from well-known computer companies, such as IBM's Systems Network Architecture( SNA), Digital Equipment Corp.'s DECnet, or Siemens' Transdata.
The network architecture is reflected in the topology, access method and other relevant characteristics. It forms the description of the appearance of a system, e.g. an operating system or a network system. It includes all functional and performance characteristics for assessing their functionality and usability. Special criteria are system resilience and connectivity or communication capability with other systems.