| Machine | Destination Equipment | Link | KB/s | Percent |
| Speed, | utilization | |||
| Mb/s | ||||
| Equipment/Control Rooms | @80% | |||
| IF SBC, Weather SBC, SCRB | Equipment Room Lan Switch | 10 | 1.5 | 0.1875 |
| DCR | Equipment Room Lan Switch | 10 | 64 | 8 |
| Spectrometer | Equipment Room Lan Switch | 10 | 0.4 | 0.05 |
| Spectral Processor | Equipment Room Lan Switch | 10 | 0.4 | 0.05 |
| VLBA Station Computer | Equipment Room Lan Switch | 10 | 0 | 0 |
| Operator Consoles | Equipment Room Lan Switch | 100 | 2000 | 25 |
| Data W.S. | Equipment Room Lan Switch | 100 | 2000 | 25 |
| Equipment Room Switch | Backbone | 100 | 150 | 1.875 |
| Engineering/Server W.S. | Control Room LAN Switch | 100 | 1000 | 12.5 |
| Observer W.S. 1 | Control Room LAN Switch | 100 | 1000 | 12.5 |
| Observer W.S. 2 | Control Room LAN Switch | 100 | 1000 | 12.5 |
| Alidade Room | ||||
| Laser SBC | Backplane Network | 10 | 8 | 1 |
| Antenna SBC | Backplane Network | 10 | 8 | 1 |
| Servo Monitor SBC | Backplane Network | 10 | 0 | 0 |
| Antenna SBC | Alidade Room LAN Switch | 10 | 15 | 1.875 |
| Servo Monitor SBC | Alidade Room LAN Switch | 10 | 20 | 2.5 |
| Laser SBC | Alidade Room LAN Switch | 10 | 40 | 5 |
| Telescope I/O SBC 1&2 | Alidade Room LAN Switch | 10 | 2 | 0.25 |
| Laser LAN Repeater | Alidade Room LAN Switch | 10 | 50 | 6.25 |
| Receiver Room LAN,SCRB | Alidade Room LAN Switch | 10 | 0 | 0 |
| Actuator Control Room LAN | Alidade Room LAN Switch | 10 | 3 | 0.375 |
| Pointing W.S. | Alidade Room LAN Switch | 100 | 110 | 1.375 |
| Alidade Room LAN Switch | Backbone | 100 | 150 | 1.875 |
| Total Backbone Traffic | 100 | 150 | 1.875 | |
| Total Control Room Switch Traffic | 1000 | 4000 | 5 | |
| Total Equipment Room Switch Traffic | 1000 | 4066.3 | 5.082875 | |
| Total Alidade Room Switch Traffic | 1000 | 150 | 0.1875 | |
Table 3 shows the estimated load on the network segments in the telescope networks shown in Figure 2 and 1. The design is based upon an Ethernet switch in the equipment room that can handle multiple Fast Ethernet segments. The data acquisition machine and the operator consoles are connected to this switch, while the 100 Mbit Fast Ethernet backbone link goes only to the alidade room switch. This topology is under consideration because it will reduce costs, while providing good performance, and allowing the network to scale even more. The maximum expected percentage utilization for any network segment on the GBT is 25%, which is the traffic from the data acquisition workstation. The maximum utilization on any network segment used for real-time control purposes is 8%. This is for the Digital Continuum Receiver, which logs its data to disk via the network. This traffic would not be active while the control commands are being issued. The traffic generated by control commands is negligible.