The Figure illustrates the cable
connections available for the various WAN types. The numbers in the
following list correspond to the numbers found in the Figure, and
the items explain the cable connections necessary for the various
WAN types:
- Asynchronous Connections
(1) -- Asynchronous
connections require RJ-11 cables that are attached
from the modem line port to the telephone company jack. If you
are using an external modem attached to a Cisco router, you
must also use a Cisco EIA/TIA-232 cable to attach the
modem to the router serial interface. The DB-60 end of
the cable connects to the router. The DB-25 end attaches to the
modem.
- ISDN BRI (2) -- ISDN
BRI connection interfaces require RJ-45 cables to connect the
BRI interface to the ISDN network. The BRI modules and BRI WAN
interface cards are available with either an S/T interface that
requires an external NT1 or a U interface that has a built-in
NT1.
- ISDN PRI (North America)
(3) -- Channelized
T1 (CT1)/PRI modules are available with or without a built-in
CSU. If you use an external CSU, attach a female DB-15 cable to
the router interface. The other end of the straight-through
cable attaches to the CSU, which in turn attaches to the ISDN
network. Routers with internal CSU modules attach directly to
the ISDN network with a standard RJ-48 connector.
- ISDN PRI (Europe) (4) -- Channelized
E1 (CE1)/PRI modules are available with balanced and unbalanced
interfaces. CE1/PRI-balanced modules provide a 120-ohm E1
interface for network connections. The unbalanced modules
provide a 75-ohm E1 interface for network connections. Four
serial cables are available from Cisco for the CE1/ PRI module.
All four cables have DB-15 connectors on the router end; they
have BNC, DB-15, twin axial, or RJ-45 connectors on the network
end.
- Frame Relay (5) -- If
you must establish a Frame Relay serial connection, Cisco
routers support the following signaling standards: EIA/TIA-232,
EIA/TIA-449, V.35, X.21, and EIA-530. Cisco supplies a DB-60
shielded serial transition cable that has the appropriate
connector for the standard you specify. The router end of the
shielded serial transition cable has a DB-60 connector, which
connects to the DB-60 port on the router serial interface.
The other end of the serial transition cable
is available with the connector that is appropriate for the
standard you specify.
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