Network Adapters and Protocols: The Issues

Windows 95 Setup automatically configures a computer to use protocols and drivers to match network components that are running when Setup is started.

If you are setting up Windows 95 for a new networking option, you must choose which types of network adapter drivers and protocols to use. Because Windows 95 has an open architecture, you have a lot of flexibility in this decision. Windows 95 supports both NDIS and Transport Driver Interface (TDI) standards, allowing Windows 95 to communicate with many other networking products and making it possible to choose from a variety of network adapters and protocols.

This section describes basic issues for choosing network adapter drivers and protocols to support your networking needs.

Choosing adapters and drivers for best performance.

Network adapters have become exceptionally reliable and inexpensive. The low cost of Ethernet adapters, including new Plug and Play hardware, means that usually the cost-effective way to improve network performance is to replace an older network adapter with a new model. The cost for the new hardware is offset almost immediately by savings in support time and improved performance. In choosing a new network adapter, you should also consider buying an adapter that matches the computer bus. For example, PCI network adapters are available for use in PCI computers.

Choosing separate protocol and adapter drivers.

With some networks, each computer's network adapter driver and protocol are separate pieces of software. With other networks, a single piece of software called a monolithic protocol stack acts as both adapter driver and protocol. Microsoft recommends that you choose separate 32-bit, protected-mode protocols and drivers rather than monolithic stacks, which run only in real mode. However, Windows 95 includes mapping technology for users who must continue to use real-mode NDIS 2 or ODI drivers.

Choosing NDIS versus ODI drivers.

Windows 95 supports NDIS versions 2.x and 3.1. All network adapter drivers and protocols shipped with Windows 95 conform to NDIS. You can use any combination of protocol and network adapter drivers that conforms to NDIS. Microsoft recommends that you use NDIS 3.1 drivers whenever possible with Windows 95.

The Open Datalink Interface (ODI) specification was defined by Novell and Apple Computer to provide a protocol and API for communicating with network adapter drivers, and to support the use of multiple protocols by a network adapter driver. To ensure the most flexibility in Windows 95, Microsoft recommends that you use NDIS 3.1 drivers whenever possible if you are running Windows 95 with Microsoft Client for NetWare Networks. If you are using a Novell-supplied network client, Novell recommends using ODI-based client software rather than monolithic IPX drivers.

Choosing a protocol.

Windows 95 can support multiple network protocols, and can share a protocol among the network providers that are installed. You might choose more than one protocol to ensure communication compatibility with all systems in the enterprise. However, choosing multiple protocols can cause more network traffic, more memory used on the local workstations, and more network delays. You probably want to choose a single protocol wherever possible. The following briefly presents some issues for each Windows 95 protocol.

For the IPX/SPX-compatible protocol:

For Microsoft TCP/IP:

For Microsoft NetBEUI:

One common method for setting up a network is to use NetBEUI plus a protocol such as TCP/IP on each computer that needs to access computers across a router. If you set NetBEUI as the default protocol, Windows 95 uses NetBEUI for communication within the LAN segment and uses TCP/IP for communication across routers to other parts of the WAN.