Daisy Chain
You can connect multiple LightBridge 2 VCL devices in a daisy chain.
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Maximum Number of LightBridge 2 VCL in a Daisy Chain |
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According to the Thunderbolt™ 2 specification, maximally 6 LightBridge 2 VCL devices can be connected in a daisy chain. The actual number of LightBridge 2 VCL devices you may integrate into a daisy chain depends on the BIOS of your host PC. |
Shared Bandwidth
The maximum DMA transfer rate of LightBridge 2 VCL is ≈ 1360 Mbyte/s. Which kind of cable you use (1 m, 2 m, 30 m optical, 60 m optical) has no influence on this value.
However, if you connect multiple LightBridge 2 VCL devices in a daisy chain, this DMA transfer rate is shared between the individual LightBridge 2 VCL devices.
Total below Maximum
As long as the total transfer rate of all LightBridge 2 VCL devices in the chain is less than 1360 Mbyte/s, you can allot the individual transfer rates quite freely.
Example (with six LightBridge 2 VCL devices connected):
LB1 |
LB2 [Mbyte/s ] |
LB3 [Mbyte/s ] |
LB4 [Mbyte/s ] |
LB5 [Mbyte/s ] |
LB6 [Mbyte/s ] |
Total transfer rate of all LBs | |
6 devices (example allotment 1) |
200 | 200 | 200 | 200 | 200 | 350 | 1350 |
6 devices (example allotment 2) |
100 | 100 | 450 | 100 | 100 | 450 | 1300 |
Total above Maximum
If the total transfer rate of all LightBridge 2 VCL devices in the chain is higher than 1360 Mbyte/s: The bandwidth available for each LightBridge 2 VCL device is allotted as follows, depending on the number of LightBridge 2 VCL connected to the chain:
LB1 |
LB2 |
LB3 |
LB4 |
LB5 |
LB6 |
Total transfer rate of all connected LBs | |
2 devices | 50% | 50% | 100% | ||||
3 devices | 50% | 25% | 25% | 100% | |||
4 devices | 50% | 25% | 12,5% | 12,5% | 100% | ||
5 devices | 50% | 25% | 12,5% | 6,25% | 6,25% | 100% | |
6 devices | 50% | 25% | 12,5% | 6,25% | 3,125% | 3,125% | 100% |
Actual values in Mbyte/s as verified with a MacMini PC running Windows:
LB1 |
LB2 [Mbyte/s ] |
LB3 [Mbyte/s ] |
LB4 [Mbyte/s ] |
LB5 [Mbyte/s ] |
LB6 [Mbyte/s ] |
Total transfer rate of all connected LBs | |
2 devices | 684,8 | 684,8 | 1369,6 | ||||
3 devices | 684,8 | 345,6 | 345,6 | 1369,6 | |||
4 devices | 684,8 | 345,6 | 172,8 | 172,8 | 1369,6 | ||
5 devices | 684,8 | 345,6 | 172,8 | 86,4 | 86,4 | 1369,6 | |
6 devices | 684,8 | 345,6 | 172,8 | 86,4 | 43,2 | 43,2 | 1369,6 |
Examples for Overflow scenarios:
LB1 |
LB2 [Mbyte/s ] |
LB3 [Mbyte/s ] |
LB4 [Mbyte/s ] |
LB5 [Mbyte/s ] |
LB6 [Mbyte/s ] |
Total transfer rate of all LBs | |
Bandwidth required by devices | 200 | 100 | 450 | 100 | 100 | 450 | 1400 |
Actually transferred Bandwidth | 200 | 100 | 450 | 100 | 100 | 410 | 1360 |
At the sixth LightBridge 2 VCL device in the chain, an overflow occurs. Only ≈ 410 Mbyte/s are transferred from this device to the host PC.
LB1 |
LB2 [Mbyte/s ] |
Total transfer rate of all LBs | |
Bandwidth required by devices (2x CL FULL) | 800 | 800 | 1600 |
Actually transferred Bandwidth | 800 | 560 | 1360 |
At the second LightBridge 2 VCL device in the chain, an overflow occurs. Only ≈ 560 Mbyte/s are transferred from this device to the host PC.
Connecting LightBridge 2 VCL Devices in a Daisy Chain
To connect multiple LightBridge 2 VCL devices physically, use Thunderbolt™ technology port B on the rear side of the chassis:
- Use a Thunderbolt™ technology cable to connect Thunderbolt™ technology port B of a LightBridge 2 VCL device with the Thunderbolt™ technology port A of the next LightBridge 2 VCL device in the daisy chain:
Rear Side with port A for connection to host PC via Thunderbolt™ technology cable
- Connect each LightBridge 2 VCL device to the power supply unit.
- Connect the power supply unit to the power outlet.
Rear side with power connector