363-206-295
System Introduction
Issue 1
December 1997
1-3
DDM-2000 OC-12 Multiplexer
Releases
1
Release Descriptions
1
The following paragraphs provide brief descriptions of the DDM-2000 OC-12
Multiplexer releases:
Release 1.0 and later features include OC-12 point-to-point with DS3 low-speed
interfaces, OC-12 hubbing with OC-3 extensions, and OC-3/OC-12 interworking
using the 21D optical line interface unit (OLIU). The TL1/X.25 message-based
interface to Bellcore's Network Monitoring and Analysis (NMA) operations system
feature comes as part of the controller hardware and separately ordered software
required with Release 1.1 and later equipment. Hardware features include the
21D OLIU, which provides a short-reach multimode proprietary optical interface
(IS-3) between the OC-3 and OC-12 shelves and the BBF2B TGS circuit pack,
which provides DS1 timing outputs. Release 1.0 includes a security feature that
offers security against unauthorized access to the CIT system functions. Logins,
passwords, and user categories are provided. Security can be enabled or
disabled.
Release 2.0 new features include OC-3/OC-12 interworking using the open
systems interconnection (OSI) 7-layer protocol stack over the data
communications channel (DCC). The OSI 7-layer protocol stack refers to the OSI
reference model, a logical structure for network operations standardized by the
International Standards Organization (ISO). Release 2.0 also includes optical
carrier level 3 concatenated (OC-3c) transport. This OC-3c transport feature can
be used to interface with broadband terminals using 21D or 21G OLIUs.
SONET synchronization messaging is used to communicate the quality of
network timing, internal timing status, and timing states throughout a subnetwork.
The OC-12 23H/23H-U OLIU provides 1550 nm optics for long reach (100 km)
central office applications.
Release 2.1 new applications include DDM-2000 OC-12/DACS IV-2000
transmission interworking with an EC-1 interface, DDM-2000 OC-12/FT-2000
OC-48 Lightwave System transmission interworking with an EC-1 interface, and
OC-12 linear extensions from OC-3 rings. New features include an EC-1 interface
with a new BBG12 3STS1E low-speed interface circuit pack, TL1 interface to
Bellcore's Operations Systems/Intelligent Network Elements (OPS/INE) Release
1.7, and additional TL1 messages to support provisioning, maintenance, testing,
performance monitoring, and security functions.
Release 2.2 new applications and features include interworking with
SLC-2000
Release 3.0, channel state provisioning, and additional TL1 commands and
enhancements.