Nortel Networks 450 - Manual (Page 253)

Media Dependent Adapters
302401-D Rev 00 C-7
There are two 1000BASE-SX (shortwave gigabit) MDA models ( Figure C-3 ):
• 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.
Figure C-3. 1000BASE-SX MDA Front Panels
Table C-3 describes the 1000BASE-SX components and LEDs.
For installation instructions, see “Installing an MDA ” on page C-11 .
1000BASE-SX
TX RX
Phy
Link
Activity
450-1SX MDA
TX RX
1000BASE-SX
RX
1000BASE-SX
TX
Activity
Link
Phy Select
450-1SR MDA
3
BS45044A
4
3 4
450-1SR MDA
(1-port redundant)
450-1SX MDA
(single port)
2 1
2 1
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