SCO UnixWare 2.1 Technical Summary - Bandwidthco Computer ...

An SCO Technical White Paper Version 2.1.2
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• DOS and Windows terminal emulator support
• Remote applications over SPX (client and server support)
NetWare Protocols
The NetWare protocol stack facilitates communication between the SCO UnixWare system and
NetWare over IPX. It allows SCO UnixWare clients to communicate with NetWare servers and
devices. It uses the native NetWare Core Protocols (NCI) to deliver requests over the network to
the NetWare kernel. In addition, the NetWare protocols allows NetWare DOS clients to access
SCO UnixWare services via terminal emulation, and it allows DOS emulators to access
NetWare services. Components of the NetWare protocols are as follows :
• IPX/RIP driver
• SPXII driver
• NVT2
• NetWare Protocol Stack Daemon (NPSD)
• Server Advertising Protocol Daemon (SAPD)
• NetWare UNIX Client (NUC) driver requester
The Internetwork Packet Exchange (IPX) protocol provides NetWare’s native datagram
service. It allows communication as an unreliable, connectionless, datagram protocol among
network nodes. The IPX driver in SCO UnixWare system (SCO UnixWare) implements both IPX
and RIP (Router Information Protocol).Enhanced SPXII provides a connection-oriented,
reliable session protocol and functions on top of the IPX protocol, adding session services. In
addition to the services provided by SPX, SPXII supports true protocol windows and negotiation
of packet size upon the establishment of a connection. Novell Virtual Terminal 2 (NVT2)
establishes connections between DOS and MS Windows workstations and SCO UnixWare host
systems by guaranteeing packet delivery and providing connection-oriented services. The
NetWare Protocol Stack Daemon (NPSD) starts up and links the protocol stacks required for
NetWare, as well as starting the SAP daemon and the NetWare management stack daemon.
The Service Advertising Protocol (SAP) Daemon (SAPD) collects service advertising packets
that can be accessed to perform server name to address mapping and get a list of advertised
services. It also performs those functions of the SAP agent that are required for IPX routers,
such as building and maintaining the Server Information Table. When SCO UnixWare is
installed on a system with a Network Interface Card already installed, the auto-discovery
feature is used to automatically detect the IPX network number, frame type, and network device
name for the network(s) connected to the node.
NetWare with UNIX Client (NUC)
The NetWare with UNIX Client (NUC) enables SCO UnixWare 2.1 to be a client to NetWare
servers (3.x and 4.x). The NUC permits SCO UnixWare users to access a NetWare file system
as if it was mounted on a SCO UnixWare system. It also supports the ability to print on a
NetWare printer from a SCO UnixWare system. The NUC provides NetWare Core Protocol
(NCP) connectivity from a SCO UnixWare 2.1 client to NetWare servers. NUC features are
enhanced over those supported on other NetWare client stations (DOS, MAC ® , OS/2 ® ,
Windows) by the multi-user, multitasking and multiprocessor capabilities of SCO UnixWare. The
NUC system provides a multi-user, multitasking, multiserver client environment for SCO
UnixWare users. Each user on the local SCO UnixWare system can access remote resources
on many different servers simultaneously. NUC maps SCO UnixWare services into NetWare,
providing a transparent interface between the SCO UnixWare operating system and the
NetWare operating system, giving the user access to directories, files and printers on remote
NetWare servers. Local UNIX operating system service semantics are preserved without
compromising NetWare security. Major components of the NUC are:
Graphical NUC client user interface desktop sup[port for NetWare client features