Installing the VPN router
34
OnSite 2800 Series User Manual
2 • Hardware installation
The signal pin-outs for the Model 2821 X.21 interface are shown in
table 6
.
The the router’s X.21 interface is wired as a DCE. No DTE configuration is possible. The router’s X.21 inter-
face requires a cable with a male DB-15 connector. Attach the male DB-15 connector of the X.21 cable to the
female DB-15 connector on the router. Attach the other end of the cable to the X.21 connector on local
modem or multiplexer device.
Installing the T1/E1 twisted pair cables.
The PRI is usually connected to a PBX or switch (local exchange
(LE)). Type and pin-outs of these devices vary depending on the manufacturer. In most cases, a straight-
through RJ-48C to RJ-48C can be used to connect to the PRI (see for E1 RJ-48C pin-out listing) with a PBX.
A cross-over cable is required to connect to an NT1, as illustrated in .
Figure 4. Rear panel of 2803K/EUI
Figure 5. Rear panel of 2803T/EUI
Table 7. Signal pin-outs for the X.21 interface on the OnSite 2800
Pin
Signal
Pin
Signal
1
Frame Ground
8
Signal Ground
2
TXDa
9
TXDb
3
CNTa
10
CNTb
4
RXDa
11
RXDb
5
INDa
12
INDb
6
SETa
13
SETb
Table 8. RJ-48C receptacle
Pin
Signal
1
TX tip
2
TX ring
3
TX shield
4
RX tip
5
RX ring
6
RX shield
