STANDARDS

The network industry uses two types of standards: de facto standards and de jure standards. To understand the concept of open systems architecture, you must be familiar with the concepts of de facto and de jure standards. De facto standards arise through widespread commercial and educational use. These standards often are proprietary and usually remain unpublished and unavailable to outside vendors. Unpublished and unavailable standards are known as closed system standards. Published and accessible standards, on the other hand, are known as open system standards. Through the growing acceptance of the concept of interoperability, many closed, proprietary systems (such as IBM's Systems Network Architecture) have started to migrate toward open system standards. Certainly, de facto standards are not always closed system standards. Some examples of proprietary open system standards include Novell's NetWare network operating system and Microsoft's Windows. The second type of standards, de jure standards, are nonproprietary, which means that no single company creates them or owns the rights to them. De jure standards are developed with the intent of enhancing connectivity and interoperability by making speci?cations public so that independent manufacturers can build to such specifications.TCP/IP, "Transport Protocols," is an example of a nonproprietary de jure standard. Several permanent committees comprised of industry representatives develop de jure standards. Some examples of these committees are

the IEEE (Institute of Electrical and Electronic Engineers) and the IRTF (Internet Engineering Task Force). Although these committees are supported by manufacturer subscriptions, and in some cases government representatives, they are intended to represent the interests of the entire community and thus remain independent of any one

manufacturer's interests. Subscribing to de jure standards reduces the risk and cost of developing hardware and software for manufacturers. After a standard has been ?nalized, a component manufacturer sub- scribing to it can develop products with some confidence that the products will operate with components from other companies that also subscribe to the same standards.

An example of a de jure standard is the set of rules that guide how web pages are transferred between computers or how ?les are trans- ferred between systems. These de jure standards are created by the IRTF to facilitate communication between different systems. One problem of de jure standards, though, is the possibility of a vendor choosing to follow only part of a given standard. The frequent result is a product that claims to conform to the standard, but that in reality fails to operate with other products in the way one might believe or expect.