IBM SC30-3681-08 Subnet mask. Synonym for address mask, Subnetwork mask. Synonym for address mask

focal point. An APPN end node can be a SOC node if it supports the function to exchange management services capabilities.

split horizon. A technique for minimizing the time to achieve network convergence. A router records the interface over which it received a particular route and does not propagate its information about the route back over the same interface.

spoo®ng. For data links, a technique in which a protocol initiated from an end station is acknowledged and processed by an intermediate node on behalf of the ®nal destination. In IBM 6611 data link switching, for example, SNA frames are encapsulated into TCP/IP packets for transport across a non-SNA wide area network, unpacked by another IBM 6611, and passed to the ®nal destination. A bene®t of spoo®ng is the prevention of end-to-end session timeouts.

standard MIB. In the Simple Network Management Protocol (SNMP), a MIB module that is located under the management branch of the Structure of Management Information (SMI) and that is considered a standard by the Internet Engineering Task Force (IETF).

static route. The route between hosts, networks, or both that is manually entered into a routing table.

station. An input or output point of a system that uses telecommunication facilities; for example, one or more systems, computers, terminals, devices, and associated programs at a particular location that can send or receive data over a telecommunication line.

StreetTalk. In the VIrtual NEtworking System (VINES), a unique network-wide naming and addressing system that allows users to locate and access any resource on the network without knowing the network topology. See also Internet Control Protocol (ICP) and RouTing update Protocol (RTP).

Structure of Management Information (SMI). (1) In the Simple Network Management Protocol (SNMP), the rules used to de®ne the objects that can be accessed by means of a network management protocol. (2) In OSI, the set of standards relating to management information. The set includes the Management Information Model and the Guidelines for the De®nition of Managed Objects

subarea. A portion of the SNA network consisting of a subarea node, attached peripheral nodes, and associated resources. Within a subarea node, all network accessible units (NAUs), links, and adjacent link stations (in attached peripheral or subarea nodes) that are addressable within the subarea share a common subarea address and have distinct element addresses.

subnet. (1) In TCP/IP, a part of a network that is identi®ed by a portion of the IP address. (2) Synonym for subnetwork.

subnet address. In Internet communications, an extension to the basic IP addressing scheme where a portion of the host address is interpreted as the local network address.

subnet mask. Synonym for address mask.

subnetwork. (1) Any group of nodes that have a set of common characteristics, such as the same network ID.

(2) Synonymous with subnet.

Subnetwork Access Protocol (SNAP). In LANs, a

5-byte protocol discriminator that identi®es the non-IEEE standard protocol family to which a packet belongs. The SNAP value is used to differentiate between protocols that use $AA as their service access point (SAP) value.

subnetwork mask. Synonym for address mask.

subsystem. A secondary or subordinate system, usually capable of operating independently of, or asynchronously with, a controlling system. (T)

switched virtual circuit (SVC). An X.25 circuit that is dynamically established when needed. The X.25 equivalent of a switched line. Contrast with permanent virtual circuit (PVC).

synchronous. (1) Pertaining to two or more processes that depend upon the occurrence of speci®c events such as common timing signals. (T) (2) Occurring with a regular or predictable time relationship.

Synchronous Data Link Control (SDLC). (1) A

discipline conforming to subsets of the Advanced Data Communication Control Procedures (ADCCP) of the American National Standards Institute (ANSI) and High-level Data Link Control (HDLC) of the International Organization for Standardization, for managing synchronous, code-transparent, serial-by-bit information transfer over a link connection. Transmission exchanges may be duplex or half-duplex over switched or nonswitched links. The con®guration of the link connection may be point-to-point, multipoint, or loop. (I)

(2)Contrast with binary synchronous communication (BSC).

SYNTAX. In the Simple Network Management Protocol (SNMP), a clause in the MIB module that de®nes the abstract data structure that corresponds to a managed object.

system. In data processing, a collection of people, machines, and methods organized to accomplish a set of speci®c functions. (I) (A)

system con®guration. A process that speci®es the devices and programs that form a particular data processing system.

system services control point (SSCP). A component within a subarea network for managing the con®guration, coordinating network operator and

710MRS V3.2 Software User's Guide