client In conjunction with NFS, a client is the computer which accesses resources that have been made available, or “shared”, by another computer (server). |
container file Physical storage medium for a file system in the POSIX file tree. A container file is a PAM file which is located on a PVS (public volume set). |
daemon Daemons are system processes which run permanently and normally in background mode, and which perform general tasks. |
directory A directory is used to group and organize files and subordinate directories of a hierarchical file systems. |
file lock Processes that work on shared files use locks to synchronize accesses to these files. A separate protocol known as "NLM" (Network Lock Manager) is implemented for working with locks in NFS. |
file system A file system is a hierarchical group of directories and files which are located physically on the same storage medium, e.g. in a partition or in a container file.The term is used for organizational structures of files, such as UNIX file system, POSIX file system, hierarchical file system, other BS2000 file systems (DMS and LMS), for example. |
file system type Type of a file system in the file tree of POSIX or of a UNIX computer. The most familiar types are as follows: |
file tree Overall hierarchy of the files on a UNIX computer or in POSIX. The UNIX or POSIX file hierarchy is organized on the basis of a tree structure. The root of the file tree is the root directory (/). All other directories are branches which emanate from the root. The files are the leaves of the tree. |
heterogeneous system environment A computer network in which computers from different manufacturers and with different operating systems communicate with each other. Synonym: open computer network. |
IP (Internet Protocol) The Internet Protocol is a protocol which selects the route in a computer network. It performs some of the functions required by Layer 3 of the OSI Reference Model. The TCP and UDP protocols are based on IP. |
LAN (local area network) A LAN is a computer network which is limited to a certain physical area. A LAN can be linked with other computer networks as a private sub network, thus forming a part of a larger network, for example a WAN. Synonyms: local computer network, local network. |
local computer The computer on which the user works directly is referred to as the local computer. |
mounting Logical, non-physical adoption of a remote resource into the local file tree. |
OSI Reference Model The model for communication between open systems, the OSI Reference Model (Open System Interconnection), provides the basis for ISO standardization of data communications. The OSI model structures the organization of communications systems and provides the basis for standardization of the protocols and services. It defines which functions must be implemented by the components involved in the communications. The OSI Reference Model consists of seven hierarchically organized layers. Specific functions within the framework of the overall communications task are assigned to each layer. |
port number A port number allows to address a particular application within a computer. It corresponds to the address of an application in a computer. The combination of Internet address and port number uniquely identifies the receiver or sender of a data packet within the network. |
POSIX file system File system on a BS2000 computer running POSIX. The POSIX file system corresponds to a UNIX file system. |
PVS (public volume set) A logical group of public (not private) BS2000 volumes. Also referred to as a pubset. |
remote computer A computer in a computer network which a user does not work with directly. The computer on which the user works directly is known as the local computer. Users can communicate with remote computers in the network. |
resource Files or directories which are used with NFS. |
root directory The directory at which the file tree begins. The root directory is represented by the slash (/). |
RPC (remote procedure call) The remote procedure call is a method which is used for communication between client and server applications in distributed processing. This method is used by NFS. A server program is identified by means of a program number, a procedure number and a version number. RPC is based on the TCP and UDP protocols. Only UDP is used by NFS in BS2000. |
server In conjunction with NFS, a server is the computer which makes resources available that can be mounted and processed by other computers (clients). |
sharing Making local resources available for mounting on remote computers; also referred to as exporting. |
TCP (Transmission Control Protocol) TCP is a connection-oriented protocol which handles data transport between two computers. Unlike UDP, TCP provides secure data transfer (end-to-end connection) and belongs to Layer 4 of the OSI Reference Model. |
transparent file access The user can access files on a remote machine like files on the local machine. |
UDP (User Datagram Protocol) UDP is a connectionless protocol which handles data transport between two computers. UDP may be placed approximately on Layer 4 of the OSI Reference Model. UDP is a datagram protocol which supports broadcasting. In contrast to TCP (secured end-to-end protocol), UDP only guarantees that the message was sent successfully. |
UFS (UNIX file system) Local file system for UNIX. |
WAN (wide area network) A WAN is a computer network which is not restricted to a spatially limited area. |