Paradyne COMSPHERE 3615 - Manual (Page 115)

Application Configurations
E-3 3615-A2-GB20-20 December 1996
Dial Backup for
Exceeded Load Thresholds
Application
Use the application shown in Figure E-2 when traffic
loading (acquiring additional bandwidth upon demand)
for the router is needed. The router must use its Backup
Load option.
Using this configuration, the router enables its
secondary serial port (EIA-232) by raising DTR when the
transmitted and received load on the primary serial port
(V.35) is greater than the value assigned for traffic-load
purposes. Raised DTR signals the DSU to establish a
backup connection to increase available bandwidth. When
the load is within threshold limits again, the router lowers
DTR, deactivating the secondary serial port. This signals
the DSU to drop the backup connection.
For example, a Cisco router can be configured as
follows:
interface serial 0
backup load 60 5
In this example, if traffic on the primary serial port
exceeds 60%, the secondary serial port is activated by the
router raising DTR. It will not be deactivated (DTR
lowered) until the combined load is less than 5% of the
primary bandwidth.
For this application, the DSU is configured like the
application in Figure E-1. Select the Synchronous Backup
for either a control or tributary (SyBC or SyBT)
configuration from the preset configurations provided by
the Configuration (Confg) branch, depending upon which
DSU you are configuring.
Figure E-2. Dial Backup for Exceeded Load Thresholds (SyBC and SyBT) Application