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OCLC Support


VDX is a standards-compliant interlibrary loan and document request management system.

VDX is also known as NRE (Navigator Request Engine) the core of the OCLC product called Navigator. Although NRE and VDX are the same product there are differences in functionality depending if VDX is stand alone or bundled with Navigator. These differences will be pointed out as you run across them in this documentation.

The following is a list of the primary differences between NRE and VDX:



The logo in the top left hand corner displays NRE

The logo in the top left hand corner displays VDX

Patrons place request using the WorldCat Group catalog

Patrons place request using ZPORTAL

NRE is configured to only search the WorldCat Z39.50 server

VDX can search any of the libraries Z39.50 enabled catalogs and WorldCat

Statistical reports are available via the link.

Stats are available via the reports link

Any Edition?

Does not use Any Edition

Both NRE/VDX enables users to:

  • Search multiple library catalogues simultaneously
  • View the bibliographic and location details of any items retrieved
  • Place a request for an item
  • Manage the request through its lifecycle, from request to receipt to return
  • Manage incoming requests from other libraries
  • Manage delivery of electronic documents (where enabled)

There are also a few changes in the terminology :



Lending string


Request number

ILL number