•The 450-1SR MDA is a single MAC MDA with a separate redundant Phy (backup Phy port). Only one Phy port can be active at any time. If the active Phy port fails, the redundant Phy port automatically becomes the active port.
•The 450-1SX MDA is a single PHY MDA.
Both models conform to the IEEE 802.3z 1000BASE-SX standard and use shortwave 850 nm fiber optic connectors to connect devices over multimode (550 meter) fiber optic cable.
Table 5 describes the 1000BASE-SX components and LEDs.
Table 5. 1000BASE-SX MDA Description
Item | Label | Description |
| | |
1 | Link | Communication link LEDs (green): |
| | On: Valid communications link. |
| | Off: The communications link |
| | connection is bad or there is no |
| | connection to this port. |
| | Blinking: The corresponding port is |
| | management disabled. |
| | (continued) |
15
