Acx1000 And Acx1100 Alarm, Management, And Clocking Cable Specifications And Pinouts - Juniper ACX1000 Hardware Manual

Dispersion is the spreading of the signal over time. The following two types of dispersion can affect an
optical data link:
• Chromatic dispersion—Spreading of the signal over time, resulting from the different speeds of light
rays.
• Modal dispersion—Spreading of the signal over time, resulting from the different propagation modes
in the fiber.
For multimode transmission, modal dispersion—rather than chromatic dispersion or attenuation—usually
limits the maximum bit rate and link length. For single-mode transmission, modal dispersion is not a
factor. However, at higher bit rates and over longer distances, chromatic dispersion rather than modal
dispersion limits maximum link length.
An efficient optical data link must have enough light to exceed the minimum power that the receiver
requires to operate within its specifications. In addition, the total dispersion must be less than the limits
specified for the type of link in Telcordia Technologies document GR-253-CORE (Section 4.3) and
International Telecommunications Union (ITU) document G.957.
When chromatic dispersion is at the maximum allowed, its effect can be considered as a power penalty
in the power budget. The optical power budget must allow for the sum of component attenuation,
power penalties (including those from dispersion), and a safety margin for unexpected losses.
ACX1000 and ACX1100 Alarm, Management, and
Clocking Cable Specifications and Pinouts
IN THIS SECTION
Alarm Contact Port Pinouts for ACX1000 and ACX1100 Routers | 86
Management Port Connector Pinout Information for ACX Series Routers | 88
Console or Auxiliary Port Connector Pinout on ACX Series Routers | 89
USB Port Specifications for an ACX Series Router | 90
External Clocking Ports Specifications on the ACX1000 and ACX1100 Router | 91
85