Servicing Information
80
WAN Interface Connection

Pinout Information

The P850 router is manufactured with three different WAN link
modules: V.35, LXT411 CSU/DSU or Universal WAN. The type
installed may be determined from the label above the WAN link output
connector on the back of the router.

V.35 Module:

The V.35 link interface is provided as a DB25 connector on the back
of the bridge/router, so an interface converter is needed to convert to
the standard V.35 connectors.
When connecting two bridge/routers back-to-back without modems, a
null-modem cable is required to crossover the pins on the links.
Crossing over the pins allows two bridge/routers both configured as
DTE interfaces to be connected together. With this configuration,
both bridge/routers will provide clocking for the links, and each
bridge/router must have a link speed defined.

CSU/DSU Module:

P850 routers with an LXT411 CSU/DSU interface module use a
standard RJ45 service connector, pinout specification RJ48S.
Figure C-4 Rear View of the CSU-DSU Connector

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CSU/DSU