Envoy ACP/XF Application Programming Manual

EnvoyACP/XF Application Programming Manual–132179
Glossary-1
Glossary
$ZZWAN. The process name for the WAN Manager subsystem that configures, starts,
manages, and monitors the WAN I/O processes through the SCF product module.
ABM. Asynchronous Balanced Mode. A mode of communications within the ADCCP
protocol whereby two combined stations communicate on a point-to-point link. Either or
both stations can issue commands to set up or dissolve the link. During data
transmission, the stations function as peers. This mode is also used by the HDLC
protocol.
ADCCP. Advanced Data Communications Control Procedures. This is the general standard
for bit-synchronous protocols. It includes two major modes of operation—ABM and
NRM. ADCCP-ABM is analogous to HDLC, and ADCCP-NRM is analogous to SDLC.
See also ABM and NRM.
address field. The field immediately following the starting flag in a bit-synchronous frame.
When stations are operating in Normal Response Mode, this field always identifies the
secondary station that is communicating with the primary station. Generally, the address
field is 1 octet long; however, with ADCCP in extended mode, the address field can be
up to four octets long. Extended address fields are not supported by the SDLC protocol
standard.
ASCII. American National Standard Code for Information Interchange. A method of coding
data, consisting of seven bits for each character, plus a parity bit. Designed for
synchronous or asynchronous use, the code has 128 standard characters.
basic control field. The default control-field length of 1 octet. See control field.
bit-synchronous. A class of serial communications protocols for data-link control. This class
includes ADCCP, HDLC, and SDLC protocols. Many wide area network architectures
define a bit-synchronous protocol as the standard link-level protocol.
CCE. Condition Code Equal, returned by a file-system procedure, indicating that the
operation was successful.
CCG. Condition Code Greater, returned by a file-system procedure, indicating an error has
occurred.
CCL. Condition Code Less, returned by a file-system procedure, indicating an error has
occurred.
CCITT. Comité Consultatif International Télégraphique et Téléphonique (International
Telegraph and Telephone Consultative Committee). A standards-setting group for
international telephone carriers.
CLIP. Communications Line Interface processor. Part of the LIU within the WAN controller,
the CLIP is a programmable process that provides link-level protocol and a software
interface to the host. The CLIP does some of the work that used to be handled by the