Cisco Headend Digital Broadband Delivery System 技术参考
2
4038990 Rev A
Overview
Acronyms
CVT
Code Version Table. The CVT is a message sent periodically by the DNCS
(network controller) that is used to trigger code image downloads for set-
tops.
(network controller) that is used to trigger code image downloads for set-
tops.
DBDS
Digital Broadband Delivery System. The entire network architecture of
our digital system that ultimately provides signal to and from a
subscriber’s DHCT. The DBDS consists of five areas: sources, headend,
transport network, hub, and access network.
our digital system that ultimately provides signal to and from a
subscriber’s DHCT. The DBDS consists of five areas: sources, headend,
transport network, hub, and access network.
DNCS
Digital Network Control System. A computer server that monitors and
controls the DBDS network elements; located at the DBDS headend or at a
remote site.
controls the DBDS network elements; located at the DBDS headend or at a
remote site.
drm
Digital Resource Manager. Manages the allocation of DBDS resources for
setting up sessions.
setting up sessions.
The drm process was part of the dsm process in system releases prior to
1.4.
1.4.
dsm
Digital Session Manager. Manages digital video sessions (broadcast and
exclusive) on the DNCS.
exclusive) on the DNCS.
When using Overlay technology, the DSM manages sessions for only our
DHCTs.
DHCTs.
osm
Operating System (OS) Manager. Allows you to load image files into the
BFS that can then be distributed to DHCTs.
BFS that can then be distributed to DHCTs.
Examples: OS images, resident application images, and other application
images.
images.
QAM
Quadrature Amplitude Modulation. A frequency modulation technique
primarily used for program audio and video. QAM supports data rates
from 27 Mbps to 36 Mbps.
primarily used for program audio and video. QAM supports data rates
from 27 Mbps to 36 Mbps.
qamManager
Quadrature Amplitude Modulation (QAM) Manager. Delivers setup
information to QAM, MQAM, and GQAM modulators.
information to QAM, MQAM, and GQAM modulators.
pkeManager
PowerKEY Element Manager. Facilitates the management of PowerKEY
Control Gateways and Netcrypt Bulk Encryptors.
Control Gateways and Netcrypt Bulk Encryptors.
RPC
Remote Procedure Call. A message sent by a client device to a remote
server requesting the server to executre a specific procedure. The message
includes applicable parameters.
server requesting the server to executre a specific procedure. The message
includes applicable parameters.