Lucent Technologies SLC ConnectReach User & Service Manual page 35

System Overview
® ™
SLC ConnectReach
Overview (Continued)
™
ClearReach
Feature
System Description
SLC-2000 Access System Software Release 4.6.1 (R4.6.1) or later along with
SLC ConnectReach operating software R1.5.1.1 or later allows the system to
support Lucent Technologies ClearReach feature. This feature is designed to
improve the connect rate, or throughput, of analog modems served by switched
single-party loop-start and ground-start lines interfacing the SLC-2000/SLC
ConnectReach system through the analog voice-frequency (VF) ports. The
SLC-2000 host digital terminal (HDT) must be connected to the TR-303/GR-303
interface of the 5ESS switch containing 5ESS software upgrade IBWM98-0008 of
5E12 software, secure feature 99-5E-4413 enabled. If the switch does not contain
this software, then the feature is not usable with the SLC-2000/SLC
ConnectReach system.
The SLC-2000 system and the SLC ConnectReach system normally use a hybrid
signaling scheme, specified in TR-303/GR-303, that incorporates the use of
robbed-bit signaling (RBS). The RBS signaling mode uses a small portion of the
bandwidth of each DS0 (64 kb/s) within the DS1 feeder for signaling thus limiting
the usable bandwidth for analog modem connections and reducing the connect
rate. The ClearReach feature allows the system to suspend RBS and convert to a
clear channel mode that makes the entire 64-kb/s bandwidth of each DS0
available for an analog modem connection. The ClearReach feature increases the
possibility that analog modems will connect closer to their rated speed.
NOTE:
A lot of different factors combine to decrease the connect rate of a modem.
These include line noise, poor physical connections, modem quality,
robbed-bit signaling used in digital telecommunications systems, etc. The
RBS used on the DS1s interfacing with the SLC-2000 system and the SLC
ConnectReach system is only one of many factors. The ClearReach feature
eliminates the interference of the RBS on the DS1s interfacing with
SLC-2000/SLC ConnectReach equipment as one of the factors decreasing
the connect rate.
Refer to document 363-208-000, SLC-2000 Access System, Applications,
Planning, and Ordering Guide, for additional information on the ClearReach
feature.
363-208-050
(Continued on next page)
Issue 4 June 2002 1-5