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Cisco uBR905 Router Hardware Installation Guide
OL-0598-01 (9/2000)
Chapter 1
Product Overview
Physical Description
Data Connectors
As shown in Figure 1-4, the Cisco uBR905 cable access router contains the following data connectors:
•
Coaxial cable F-connector —Provides the connection to the CMTS and cable network. The coaxial
cable connector is a single cable interface (Cable 0) and must always be connected to the cable
system for proper operation.
•
Four Ethernet 10Base T hub ports—Provides connectivity to the subscriber CPE devices. The
Ethernet ports are in a hub configuration that forms one logical Ethernet interface (Ethernet 0).
When the Cisco uBR905 router transmits data to the Ethernet interface, it is broadcast out all four
ports.
CPE devices can be connected to the Ethernet ports using one of the following configurations:
–
If the router is configured for bridging mode, from one to four CPE devices can be connected
directly to the router.
–
If the router is configured for bridging mode, an Ethernet hub can be connected to one of the
router’s Ethernet ports. The hub can then in turn be connected to up to 254 additional CPE
devices.
LINK
Cable RF Link
Green
On = Cable connection up; RF link up
Blink = Cisco uBR905 is searching for a downstream frequency
Off = Cable connection down; RF link down
DS
1
Downstream Signal
Lock Status
Green
On = Cisco uBR905 is locked to a downstream frequency (channel).
Off = Cisco uBR905 has not yet locked to a downstream frequency (channel) or
the router has not yet located a digital signal.
US
Upstream
Signal
Quality
Green
On = Cisco uBR905 has established upstream communications with the CMTS;
cable access router has completed ranging state 2 (as per DOCSIS), has entered
provisioning state, and is communicating within 6 dB of desired final power level
(generally within 3 dB).
Off = Cisco uBR905 has not completed secondary ranging; the CMTS has heard
from the cable access router, however, and there is some upstream continuity.
Downstream
Signal-to-Noise
Ratio
Green
On = Receiving quality, downstream signal; SNR is greater than 5 dB above the
downstream lock threshold.
Off = Receiving low or marginal downstream signal strength or quality.
Note
The signal is checked approximately every 25 seconds and the DSNR
LED is updated to reflect the current state. If this LED remains off, it
could indicate a problem with the cable at the subscriber’s site.
MSG
Message Waiting
Green
No default function defined. The service provider can use SNMP set requests to
use this LED for custom applications or services.
1.
These are the Cisco factory-default LED settings. Configuration control messages can be sent to the Cisco uBR905 cable access router through Simple
Network Management Protocol (SNMP) set requests. Using Management Information Base (MIB) objects in the Cisco cable device MIB, the CMTS
system administrator can define these LEDs to have other meanings.
Table 1-1
Cisco uBR905 Cable Access Router Front Panel LED Description (continued)
Label
Description
Color
Function