Network Protocol Basics

Windows 95 network protocols are implemented as 32-bit, protected-mode VxDs that offer high performance and use no conventional memory. Windows 95 can support multiple protocols simultaneously, and protocol stacks can be shared among the installed network clients. For example, the IPX/SPX-compatible protocol can support both Client for NetWare Networks and Client for Microsoft Networks. The following protocols are included with Windows 95.

Microsoft IPX/SPX-compatible protocol.

This protocol is compatible with the Novell NetWare Internetwork Packet Exchange/Sequential Packet Exchange (IPX/SPX) implementation. Windows 95 includes both 32-bit, protected-mode and real-mode support for this protocol. This protected-mode protocol provides the following benefits:

• Support for any Novell NetWare-compatible network client
• Support for packet-burst mode to offer improved network performance
• Support for the Windows Sockets, NetBIOS, and ECB programming interfaces
• Support for automatic detection of frame type, network address, and other configuration settings
• Connectivity with servers and workstations on NetWare or Windows NT Server 3.5 networks, and mixed networks
• Routable for connectivity across all network bridges and routers configured for IPX/SPX routing

Microsoft TCP/IP.

This is a complete implementation of the standard, routable Transmission Control Protocol/Internet Protocol (TCP/IP) protocol. Windows 95 includes only protected-mode support for this protocol. Microsoft TCP/IP provides the following benefits:

• Support for Internet connectivity and the Point-to-Point Protocol (PPP) used for asynchronous communication
• Connectivity across interconnected networks with different operating systems and hardware platforms, including communication with many non-Microsoft systems, such as Internet hosts, Apple® Macintosh® systems, IBM® mainframes, UNIX® systems, and Open VMS™ systems
• Support for automatic TCP/IP configuration using Windows NT Dynamic Host Configuration Protocol (DHCP) servers
• Support for automatic IP-address-to-NetBIOS computer name resolution using Windows NT Windows Internet Naming Service (WINS) servers
• Support for the Windows Sockets 1.1 interface, which is used by many client-server applications and many public-domain Internet tools
• Support for the NetBIOS interface, commonly known as NetBIOS over TCP/IP
• Support for many commonly used utilities, which are installed with the protocol

Microsoft NetBEUI.

This protocol is compatible with existing networks that use NetBIOS extended user interface (NetBEUI), including Windows for Workgroups peer networks, Windows NT Server, LAN Manager, and other networks, and includes support for a NetBIOS programming interface. Windows 95 provides both protected-mode and real-mode support for this protocol.

NetBEUI was first introduced by IBM in 1985, when it was assumed that LANs would be segmented into workgroups of 20 to 200 computers and that gateways would be used to connect one LAN segment to other LAN segments or to a mainframe. NetBEUI is optimized for high performance when used in departmental LANs or LAN segments. Microsoft NetBEUI under Windows 95 is completely self-tuning and provides much better performance over slow links than did earlier versions of NetBEUI.

All three protocols are Plug and Play-compliant, so they can be loaded and unloaded automatically. For example, if a PCMCIA network adapter is removed from the computer so that the network is no longer available, the protocols are unloaded automatically after any dependent applications have been notified.