Multiservice Networking, IPX Networking, and Security - CCIE Routing and Switching Exam Certification Guide - page 567

Network Basic Input/Output System (NetBIOS)
NetWare also supports the (NetBIOS) session layer interface specification from Sytek. Novell's
NetBIOS emulation software allows programs written to the industry-standard NetBIOS
interface to run within NetWare system.
The NetWare shell runs clients (often called workstations in the NetWare community) and
intercepts application input/output (I/O) calls to determine whether they require network access
for completion. If the application request requires network access, the NetWare shell packages
the request and sends it to lower-layer software for processing and network transmission. If the
application request does not require network access, the request is passed to the local I/O
resources. Client applications are unaware of any network access required for completion of
application calls.
Get Nearest Server (GNS)
Clients learn their network number by sending a GNS broadcast. Servers on the local segment
respond to the broadcast and the client selects a server. If no servers are on the local segment,
the router responds to the GNS.
On the router, a GNS request for a file server chooses the server at the top of its respective type
portion of the table if all servers have the same metric and hop count. Whenever a file server is
taken out of service and then put back in service sometime later, it is put back in the Service
Advertising Protocol (SAP) table at the top of the list for its respective type/metric.
NetWare Directory Services (NDS)
NDS is a distributed information database that stores information about all Internet, intranet,
and network resources on a network. NDS is a directory service that can store and manage
millions of objects, such as users, applications, network devices, and data. NDS natively
supports the directory standard Lightweight Directory Access Protocol (LDAP) version 3 over
Secure Socket Layer (SSL).
The NDS directory is a list of objects that represent network resources, such as network users,
groups, servers, printers, print queues, and applications. It provides a single, global, and logical
view of all network resources and services. The NDS directory also provides single logon
applications.
NDS organizes resources or objects in a hierarchical tree structure. The organization can
arrange resources in the directory tree according to the policies and procedures unique to the
company.