NetWare 4.1/9000 Concepts

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NetWare Glossary
V
V
Value-added server
A separate, specialized, dedicated computer (such as a print server or a
database server) that fulfills a specific function for network users.
Virtual Loadable Module (VLM)
A modular executable program that runs at each DOS workstation and
enables communication with the NetWare server.
A VLM file has a .VLM filename extension. For example, the IPX VLM file
is IPXNCP.VLM.
The NetWare DOS Requester is composed of several VLMs. These VLMs
replace, and provide backward compatibility with, NetWare shells used in
previous NetWare versions.
There are two types of VLMs: child VLMs and multiplexor VLMs.
Child VLMs
Child VLMs handle a particular implementation of a logical grouping of
functionality. For example, each NetWare server type has its own child
VLM:
• NDS.VLM, for NetWare Directory Services-based (NetWare 4) servers.
• BIND.VLM, for bindery-based servers (prior to NetWare 4).
• PNW.VLM, for NetWare desktop-based servers.
Various implementations of transport protocols also have their individual
child VLMs. For example, IPXNCP.VLM handles IPX services, and
TCPNCP.VLM handles TCP functions.
Multiplexor VLMs
A multiplexor is a VLM that routes calls to the proper child VLM. Requester
multiplexors can be considered parent VLMs, ensuring that requests to child
VLMs reach the appropriate VLM module.