Nortel Networks 1750 User Manual

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Chapter 1 Cables and power 31
Nortel VPN Router Installation — VPN Router 1750 
56/64K CSU/DSU WAN interface card LEDs
The following figure shows the LEDs on the 56/64K CSU/DSU WAN interface 
card.
Figure 8   LEDs on the 56/64K CSU/DSU WAN interface card
The following figure describes the LEDs on the 56/64K CSU/DSU WAN interface 
card.
Table 9   LED indicators on the 56/64K CSU/DSU WAN interface card
LED
Description
Blue
The blue alarm LED lights after the interface card detects a digital data 
service (DDS) out-of-frame condition on the receive signal.
Red
The red alarm LED lights after the interface card detects a DDS loss-of- 
signal or loss-of-frame condition on the receive signal.
Yellow
The yellow alarm LED lights after the interface card detects a DDS 
out-of-service condition on the receive signal. This LED indicates that 
the far-end equipment detects a local loss of service (LOS) or loss of 
frame (LOF) condition.
Green
The green LED lights after the interface card receives valid DDS signal 
and framing. This LED indicates normal operation of the card.
All LEDs off
The port is disabled.
56/64K
DDS
Blue LED 
Yellow LED 
Red LED
Green LED