Understanding the NetWare Client Software

The NetWare DOS Requester Architecture

The NetWare DOS Requester Architecture

The NetWare DOS Requester consists of a group of files that provide NetWare support for DOS and MS Windows client workstations. These files consist of a number of Virtual Loadable Module™ (VLM) files and a single executable file (VLM.EXE) which manages operation of the .VLM files.

Full understanding of the NetWare DOS Requester architecture requires you to understand these components, as discussed in the following sections:

•Three-Layer Structure

•VLM Manager

•Connection Table Manager

•Backwards Compatibility with NETX Applications

•File and Print Services

•Memory Usage

See “NetWare DOS Requester Option” in Chapter 2, “NET.CFG Options Reference,” in NetWare Client for DOS and MS Windows Technical Reference for information on configuring this option for optimizing your client workstations.

Three-Layer Structure

The .VLM files are grouped into the following three layers:

•DOS Redirection Layer

•Service Protocol Layer

•Transport Protocol Layer

The following figure shows how these layers and modules fit together. Individual pieces are discussed in further detail in the sections that follow.

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