in a communications configuration.
communications setup. A
stored pro-file that defines the operating char-acteristics (such as protocol and codeset) of a communications session between a Displaywriter and a remote station. For any communication to
take place, at least one setup must be stored on the BSC program diskette.
Connection Point Mnnager. A component of the transmission control layer that coordinates the normal and expedited flows for a half-session; functions performed include session pacing, sequence numbering, routing, building/interpreting the RH.
CPU. Central processing uit.
CR. Carrier Return.
CRC. Cyclic Redundancy Check Charac-ter.
CRE. Carriage Return.
CRV. Cryptography Verification
CUn. Customer use number (the letter
DACTCDRH. Deactivate Cross-domain Resource Manager
DACTLU (Deactivate Logical
Unit). Ends a session between SSCP and the LU addressed.
DACTPU (Deactivate Physical
Unit). Ends a session between SSCP
request/respons~ unit (RU) category used for requests and responses exchanged between the data flow con-trol layer in one half-session and the data flow control layer in the session partner.
Data Communication Equipment
(DeE). The common carrier's lines, devices and facilities that intercon-nect data terminal equipment.
Data Link Control (DLC). The layer which schedules data transfer on the link and performs error control for the link.
Data Signaling Rate. The aggregate signaling rate in the transmission path of a data transmission system, expressed in normalized form in binary digits (bits) per second (BPS).
Data Set Ready (DSR). A circuit that initiates the communications link once DTR has been activated.
Data
Terminnl
Equip~cnt (DTE). That part of a business machine that serves as a source, data sink, or both, and provides for the data communication control function according to proto-cols.Dnt~ Termin~l Re~dy (DTR). A circuit that activates the communications hardware.
DeE. Data Communication Equipment.
Data Link
Escape
Char~cter (DLe).A
transmission control character that changes the meaning of a limited num-ber of contiguously following charac-ters or coded representations and that is used exclusively to provide supple-mentary transmission controlcharacters.
DCn. Device Control number (the let-ter n represents a numeric value).
Dead Kay. A function on World Trade keyboards that prevents the ~achine
from advancing to the next key when
response whether positive or negative.
DEL. Delete.
Dest;n~tion Address Field (DAF). A field in the TH that contains the net-work address of the destination.
os.
Digit Select.DTE. Data Terminal Equipment
duplex line. A communications line with two independent data paths over which data can be transmitted in both directions simUltaneously.
EBCDIC. Extended binary coded decimal interchange code. A coded character set consisting of 8-bit coded charac-ters. See code set.
ECBS. Error Correct Backspace.
EIA. Electronics Industries Associ-ation. An organization that promotes standardization and cooperation among electronic equipment industries.
EIA RS-232C Interf~ce. The standard interface for communications that pro-vides signal conversion for obtaining the voltage levels specified in the EIA Specification RS-232C and the CCITT Recommendation V.28. For the
Displaywriter system, the interface is packaged on the communications adapter card and is connected to an external destination of information flowing within a network. transmission- checking information.
FF. Form Feed. data exchanged between logical units
(LUs) and for requests and responses exchanged between network services components of LUs, PUs, and SSCPs.
FMT. Format.
Format Identification Type
(FID). Indicates the format of the Transmission Header (TH).
Frame. The SOLC transmission unit. destina-tion or characteristics.
Function Managem~nt Profile. A spec-ification of data flow protocols sup-ported for a particular session.
GE. Graphic Escape.
GS. Group Separator.
half-duplex line. A communications line with a single data path over which data can be transmitted in either direction (but not
simultaneously).
Half-Session. A component that pro-vides FMD services, OFC, and TC for
IFS. Interchange File Separator.
IGS. Interchange Group Separator.
INP. Inhibit Presentation (Bypass) INX. Index.
IPR. Isolated Pacing Response.
IRS. Interchange Record Separator.
IRT. Index Return.
IT. Indent Tab.
ITB. Intermediate Transmission Block IUS. Interchange Unit Separator.
Last in Chain (LIC). A bit in the RH com-munication between locally-attached machines.
logical Session Id~ntifier
(LSID). The address in th FlO 3 Transmission Header (TH).
logical unit. An NAU having protocol boundries with end users. A port through which an end user accesses the network.
Longitudinal Redundancy Check (LRC). A system of error checking
performed at the recelvlng station
multipoint network. A configuration in which more than two terminal
installations are connected. The net-work may include switching facilities.
NAK. Negative Acknowledge.
NAU. Network Addressable Unit NBS. Numeric Backspace.
NCP. Network Control Program NDM. Normal Disconnect Mode.
Network Addressable Unit (NAU). An LU, PU, or SSCP. It is the origin or destination of information transmitted by the path control network.
Network Control Program (NCP). A pro-gram which resides in the 3704/3705 communication controller and controls
its operation. commu-nications line is permanently con-nected to a station.
NRM. Normal Response Mode.
NSP. Numeric Space.
NUL. Null.
OCL. Operator Control Language.
only In Chain (OIC). A bit in the RH which indicates this PIU is a single element chain.
Operator Control Lan9Unge (OCLl. A programming language used with the
Office System 6 family of word session, congiguration, maintenance and management, and network operator services.
PIU. Path Information Unit.
POC. Program-Operator Communication.
point-to-point. A data link that con-nects a single remote station to a host;
it may either be switched or non-s~ ... itched.
PP. Presentation Position.
PRE. Prefix.
Primary LU (PLU). The LU that sends the session activation request.
PU. Physical Unit.
QC. Quiesce Complete
QEC. Quiesce at End of Chain
quiesce. An SHA protocol that stops the sending of normal flow requests.
RCR. Required Carrier Return.
Ready to Receive (RTR1. An SNA com-mand used in bracket protocol by the first speaker to give the bidder per-mission to start a bracket.
REClUS. Request Maintenance Statistics RELQ. Request Quiesce
Re~ote Job Entry (RJE). Submission of a job through an input unit that has access to a computer through a data link.
REQDISCOHT. Request Discontact
Requ~st D~f;n;te Response
(RQDJ. Indicates an LU has coded the RH to request a definite response from its session partner.
Requ~st Exception Response
(RQE). Indicates an LU has coded the
RH to request a response from its ses-sion partner only if it is negative.