Appendix
25
2.3.2 Constraints for Networks
The 100M Ethernet Control LAN basically complies with the IEEE802.3u specification. However, there
are some constraints for the TOSDIC-CIE DS system. Construct your network system under the
constraints below.
(1) The lengths of twisted pair cable are as shown in the following table.
Table 2.1 Twisted Pair Cable Length
Maximum Length
Cable Type
Remarks
Switching Hub
∼
Station
30m
Straight
See Figure 2.2
Hub
∼
Station
30m
Straight
See Figure 2.2
Switching Hub
∼
Hub
30m
Cross
See Figure 2.3
Switching Hub
∼
Switching Hub
30m
Cross
-
FX-TX Conversion Module
∼
Station
30m
Straight
See Figure 2.4
FX-TX Conversion Module
∼
Switching
Hub
3m
Straight
See Figure 2.4
FX-TX Conversion Module
∼
Hub
3m
Straight
See Figure 2.6
(2) The lengths of optical fiber cord/cable are shown in the following table.
Table 2.2 Optical Fiber Length
Maximum Length
Remarks
Switching Hub
∼
Switching Hub
2km
See Figure 2.4
Switching Hub
∼
Station
2km
See Figure 2.5
Switching Hub
∼
Hub
150m
See Figure 2.6
Hub
∼
Station
150m
See Figure 2.7
(3) The maximum number of stages for switching hubs is 2. (See Figure 2.8)
Due to the delay time in switching hubs, the maximum number of stages for switching hubs is 2 for
the TOSDIC-CIE DS system to ensure the response time between OIS and PCS. Therefore, the
maximum transmission distances are as shown in Table 2.3.
Table 2.3 Transmission Distance
10M-Ethernet
100M-Ethernet
Maximum Transmission Distance
2.5km
8.0km
(4) Cascade connection between shared hubs is not allowed. (See Figure 2.9)