Isdn Bri Connections - Cisco WS-C2950-24 Installation Manual

Chapter 2 Preparing for Router Installation
Table 2-3
Rate (bps)
2400
4800
9600
19200
38400
56000
1544000 (T1)
Balanced drivers allow EIA/TIA-449 signals to travel greater distances than EIA/TIA-232 signals. The
recommended distance limits for EIA/TIA-449 shown in
EIA-530. Typically, EIA/TIA-449 and EIA-530 can support 2-Mb/s rates, and V.35 can support 4-Mb/s
rates.
Asynchronous/Synchronous Serial Module Baud Rates
The following baud-rate limitations apply to the slow-speed serial interfaces found in the
asynchronous/synchronous serial modules:
•
•

ISDN BRI Connections

BRI WAN interface cards provide ISDN BRI connections. The BRI modules and BRI WAN interface
cards are available with either an S/T interface that requires an external Network Terminator 1 (NT1),
or a U interface that has a built-in NT1.
You can install the BRI modules in any available slot in the chassis.
Hazardous network voltages are present in WAN ports regardless of whether power to the unit is OFF
Warning
or ON. To avoid electric shock, use caution when working near WAN ports. When detaching cables,
detach the end away from the unit first. Statement 1026
Use a BRI cable (not included) to connect the BRI WAN interface card directly to an ISDN.
lists the specifications for ISDN BRI cables. Also, see the
Specifications
OL-18712-02
Serial Signal Transmission Speeds and Distances
Distance for
EIA/TIA-232
Feet Meters
200 60
100 30
50 15
25 7.6
12 3.7
8.6 2.6
— —
Asynchronous interface—Maximum baud rate is 115.2 kbps.
Synchronous interface—Maximum baud rate is 128-kbps full duplex.
document at Cisco.com for pinouts.
Distance for
EIA/TIA-449, X.21, V.35,
and EIA-530 Distance for USB
Feet Meters Feet
4100 1250 16.4
2050 625 16.4
1025 312 16.4
513 156 16.4
256 78 16.4
102 31 16.4
50 15 16.4
Table 2-3
Cisco Modular Access Router Cable
Cisco 2900 Series and 3900 Series Hardware Installation Guide
Network Cabling Specifications
Meters
5
5
5
5
5
5
5
are also valid for V.35, X.21, and
Table 2-4
2-11