Distance Limitations
Serial signals can travel a limited distance at any given bit rate; generally, the slower the data rate, the greater
the distance. All serial signals are subject to distance limits, beyond which a signal significantly degrades or
is completely lost.
The following table lists the recommended maximum speeds and distances for each serial interface type;
however, you might get good results at speeds and distances greater than those listed, if you understand the
electrical problems that might arise and can compensate for them.
Table 4: Serial Signal Transmission Speeds and Distances
Distance for EIA/TIA-232
Rate (bps)
Meters
Feet
60
200
2400
30
100
4800
15
50
9600
7.6
25
19200
3.7
12
38400
2.6
8.6
56000
—
—
1544000 (T1)
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:
• Asynchronous interface—Maximum baud rate is 230 kbps.
• Synchronous interface—Maximum baud rate is 256 kbps full duplex.
Required Tools and Equipment for Installation and Maintenance
You need the following tools and equipment to install and upgrade the router and its components:
• ESD-preventive cord and wrist strap
• Number 2 Phillips screwdriver
• Phillips screwdrivers: small, 3/16-in. (4 to 5 mm) and medium, 1/4-in. (6 to 7 mm)
• Screws that fit your rack
In addition, depending on the type of modules you plan to use, you might need the following equipment to
connect a port to an external network:
• Cables for connection to the WAN and LAN ports (dependent on configuration).
Ethernet hub or PC with a network interface card for connection to an Ethernet (LAN) port.
Cisco Catalyst IR8340 Rugged Series Router Hardware Installation Guide
20
Preparing for Router Installation
Distance Limitations