定义企业信息门户EIP（英文版）.PDF23

1.1 Definition
In the general sense of the word, ‘portal’ can be defined as a web application
that offers a single interface and access to various information sources. This
definition has the virtue of clearly positioning the problem and representing
quite concisely the manner in which each person may interpret this term
within a context linked to information systems.
However, such a definition may seem a tad simplistic for many reasons.
Firstly, a portal is not dedicated exclusively to a web interface. New
communication modes such as the WAP interface and PDAs can also offer
portals, albeit portals limited in terms of content. Secondly, the notion of
information source is up for discussion as well. While portals were originally
designed to deliver information, their ability to federate applications obviously
contributed to their success within enterprises as well. These applications
usually come from one of three different sources: legacy applications that are
inserted directly into the portal, “closed” legacy applications for which the
interface must be adapted, and applications offered by portal-solution
vendors.
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