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Wide area networks differ from local area networks in that they typically do not have the same distance limitations; however, WANs are limited in the data rates that they can accommodate.
Two basic types of links are used in WANs:
Point-to-point WAN connections can be permanent or on-demand connections. Novell provides an implementation of the Point-to-Point Protocol (PPP) in the basic Novell Internet Access Server 4.1 package. Refer to Understanding in the NetWare Link/PPP documentation for more information.
Two common packet-switched networks are currently available: frame relay and X.25.
Frame relay is a relatively new service aimed at reducing network delays, utilizing the available communications bandwidth more efficiently, and lowering equipment costs. The frame relay service might eventually replace the X.25 service, but it does not currently offer the same embedded error protection capabilities that X.25 provides.
X.25 is the predominant packet-switching protocol in use in the United States and most of Europe. X.25 was developed by the ITU-T (International Telecommunications Union, Telecommunications Standardization sector), previously CCITT, in the late 1970s and was later adopted by the International Standards Organization (ISO).
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