Cisco 7000 Hardware Installation And Maintenance page 79

Table 2-4 E1-G.703/G.704 Maximum Cable Lengths
Connection Type BNC
Balanced –
Unbalanced 600m
Token Ring Connections
Currently there is no maximum transmission distance defined for IEEE 802.5 (Token Ring)
networks. Shielded twisted-pair cabling is most commonly used for rates of 16 Mbps, and either
shielded or unshielded twisted-pair cabling is used for rates of 1 and 4 Mbps. When planning your
connections, remember that twisted-pair cabling is more susceptible to interference than other types
of cabling, so plan the total network length and repeater spacing accordingly.
Fiber (FDDI) Connections
The FDDI standard sets the maximum distances between stations to the fiber lengths shown in
Table 2-5. The maximum circumference of the FDDI network is only half the specified distance
because of signal wrapping or loopback during fault correction. The standard allows a maximum of
500 stations. Both single-mode and multimode transceiver types provide 11 dB of optical power.
Table 2-5 FDDI Maximum Transmission Distances
Transceiver Type Max. Distance Between Stations
Single-mode 6.2 miles (up to 10 km)
Multimode 1.2 miles (up to 2 km)
Serial Connections
As with all signaling systems, serial signals can travel a limited distance at any given bit rate;
generally, the slower the baud rate, the greater the distance. Table 2-6 shows the standard
relationship between baud rate and distance for EIA/TIA-232 signals.
Table 2-6 IEEE Standard EIA/TIA-232C Transmission Speed Versus Distance
Rate (bps) Distance (Feet)
2400 200
4800 100
9600 50
19200 25
38400 12
56000 8.6
Balanced drivers allow EIA/TIA-449 signals to travel greater distances than EIA/TIA-232.
Table 2-7 shows the standard relationship between bit rate and distance for EIA/TIA-449 signals.
Twinax
300 meters (m)
–
Distance (Meters)
60
30
15
7.6
3.7
2.6
Site Requirements
Preparing for Installation 2-75