Source Routing:-

IBM's Token Ring method of routing data frames through is network consisting of multiple local-area networks (LANs) by specifying the route to be traveled in each frame. The route is actually determined by the end stations through a discovery process supported by source-bridge routers. IBM bridges can be of two types:

• Single-route broadcasting: Allows certain bridges to pass the pocket, so that only a single copy arrives on each ring in the network.

• All-routes broadcasting: - Sends the packet across all the possible routes in the network, so as many copies of the packet arrive at the destination as there are bridges in the network.

Spanning Tree:-

A network segment that is free of logical loops; a network structure that has a root node and one path, usually the shortest distance that connects all the other nodes. This tree structure is used in bridged networks to make routing decisions, especially if multiple paths connect nodes, because these loops could lead to packets looping on their way to their destination.

SPARCstation:-

A Sun Microsystems family of UNIX workstations based on the SPARC processor. SPARCstations range from small, diskless desktop systems to high performance, tower servers in multiprocessor configurations.

SPX:-

Abbreviation for Sequenced Packet Exchange. A set of Novell NetWare protocols implemented on top of IPX to form a transport-layer interface. SPX provides additional capabilities over IPX. For example, it guarantees packet delivery by having the destination node verify that the data was received correctly. If no response is received within a specified time, SPX retransmits the packet. If several retransmissions fail to return an acknowledgement, SPX assumes that the connection has failed and informs the operator. All packets in the transmission are sent in sequence, and they all take the same path to their destination node.

StarLAN:-

A network operating system from AT&T that implements CSMA/CD protocols on twisted-pair cable (TP) transmitting at 1 megabit per second (Mbps); a subset of 802.3. In 1988, StarLAN 10 was launched. StarLAN 10 is a 10 Mbps Ethernet version that uses TP or fiber-optic cable.

Star Network:-

A network topology in the form of a star. At the center of the star is a wiring hub or concentrator, and the nodes or workstations are arranged around the central point representing the points of the star. Wiring costs tend to be higher for star networks than for other configurations, because each node requires its own individual cable. Star networks do not follow any of the IEEE standards.

Straight-tip Connector:-

Abbreviated ST. A fiber optic cable connector that maintains the perfect alignment of the ends of the connected fibers, required for efficient light transmission.

Streams:-

A function of UNIX that provides flexible communications paths between processes and device drivers.

StreetTalk:-

The distributes global naming and directory service for Banyan VINES network operating system. The StreetTalk database contains all the necessary information about all nodes and devices on the network, and this database is updated every 90 seconds. Under StreetTalk, all users, printers, and servers have a three part StreetTalk address in the form of device or user name, .domain name, and organization name; StreetTalk  also allows nicknames for nodes and devices.

Structured Wiring:-

A planned cabling system for enterprise-wide network communications, including both voice and data. AT&T's Premises Distribution Systems and IBM's Cabling System are both structured wiring designs.

SuperPipelining:-

A preprocessing technique used by some microprocessors in which two or more execution stages (such as fetch, decode, execute, or write back) are divided into two or more pipelined stages, giving considerably higher performance.

SuperServer:-

A computer specifically designed for use as a network server. A superserver is a very high-performance system, often characterized by scalable input/output channels, complex multiprocessing features, and a large price tag. It may have several central processing units (CPUs), large amounts of error -correcting memory, cache memory, and hard-disk space, as well as fault-tolerant features, such as redundant power supplies.

SuperUser:-

A special UNIX privilege level, with unlimited access to all files, directories, and commands that allows system managers to perform certain functions.

Swap file:-

On a hard disk, a file used to store parts of running programs that have been swapped out of memory temporarily to make room for other running programs. A swap file may be permanent, always occupying the same amount of hard-disk space even though the application that created it may not be running, or temporary, created as and when needed.

Swapping:-

The process of exchanging one item for another. In a virtual memory system, swapping occurs when a program requests a virtual memory location that is not currently in memory. Swapping may also refer to changing floppy disks as needed when using a single floppy disk drive.

Symmetrical Multiprocessing:-

A multiprocessing design that assigns a task to a processor in response to system load as the application starts running. This design makes for a much more flexible system than asymmetrical multiprocessing, in which the programmer matches a specific task to a certain processor while writing the program. In symmetrical multiprocessing, the overall workload is shared by all processors in the system; system performance increases as more processors are added into the system. The draw back is that symmetrical multiprocessing operating systems are much harder to design than asymmetrical multiprocessing operating systems.

Synchronization:-

The timing of separate elements or events to occur simultaneously. In computer-to-computer communications, the hardware and software must be synchronized so that file transfers can take place.

Synchronous Transmission:-

A transmission method that uses a clock signal to regular data flow. In synchronous transmissions, frames are separated by equalized time intervals. Timing must be controlled precisely on the sending and the receiving computers. Special characters are embedded in the data stream to begin synchronization and to maintain synchronization during the transmission, allowing both computers to check for and correct any variations in timing.

SysCon:-

A Novell NetWare 3.x workstation utility used to manage the file servers on the network; most of the supervisory tasks associated with the file server can be performed with SYSCON, including setting up accounts and account restrictions, assigning file-system rights, and managing users. In NetWare 4x\ these functions are performed through NETADMIN or NWADMIN.

Systems Application Architecture:-

Abbreviated SAA. A set of IBM standards, first introduced in 1987, that defines a consistent set of interfaces for future-IBM software. Three standards are defined:

• Common User Access (CUA): A graphical user, interface definition for products designed for use in an object-oriented operating environment. The OS/2 desktop follows CUA guidelines in its design, and Microsoft Windows implements certain CUA features.

• Common Programming Interface (CPI): A set of Application Programming Interfaces (APIs) designed to encourage independence from the underlying operating system. The standard database query language is Structured Query Language (SQL).

• Common Communications Support (CCS): A common set of communications protocols that interconnect SAA systems and devices.

[Previous 15 | Next 15]