Cb-Re And Rcb Interface Cable And Wire Specifications For Mx Series Routers - Juniper MX204 Hardware Manual

P = 13 dB – 2 km (1 dB/km) – 5 (0.5 dB) – 2 (0.5 dB) – 0.5 dB
M
P = 13 dB – 2 dB – 2.5 dB – 1 dB – 0.5 dB
M
P = 7 dB
M
The following sample calculation for an 8-km-long single-mode link with a power budget (P
uses the estimated values from
(8 km @ 0.5 dB/km, or 4 dB) and loss for seven connectors (0.5 dB per connector, or 3.5 dB). The power
margin (P ) is calculated as follows:
M
P = P – LL
M B
P = 13 dB – 8 km (0.5 dB/km) – 7(0.5 dB)
M
P = 13 dB – 4 dB – 3.5 dB
M
P = 5.5 dB
M
In both examples, the calculated power margin is greater than zero, indicating that the link has sufficient
power for transmission and does not exceed the maximum receiver input power.
CB-RE and RCB Interface Cable and Wire Specifications for MX Series
Routers
Table 23 on page 65 lists the specifications for the cables that connect to management ports and the wires
that connect to the alarm relay contacts.
NOTE: In routers where the Routing Engine (RE) and Control Board (CB) are integrated into a single
board, a CB-RE is known as Routing and Control Board (RCB). The RCB is a single FRU that provides
RE and CB functionality.
Table 23: Cable and Wire Specifications for Routing Engine and RCB Management and Alarm Interfaces
Cable
Port Specification
Routing Engine RS-232
console or (EIA-232) serial
auxiliary cable
interface
Table 22 on page 64 to calculate link loss (LL) as the sum of fiber attenuation
Cable/Wire Maximum
Supplied Length
1.83-m length 1.83 m
with
RJ-45/DB-9
connectors
B
Router
Receptacle
RJ-45 female
65
) of 13 dB