Nortel Networks 450 manual Figure C-3 BASE-SX MDA Front Panels

Media Dependent Adapters

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.

450-1SR MDA	1	2
(1-port redundant)

1000BASE-SX1000BASE-SX

TX RX TX RX

Link

Phy Select

Activity

450-1SR MDA

	4	3
450-1SX MDA	1	2

(single port)

1000BASE-SX

TX RX

Link

Phy

Activity

450-1SX MDA

43

BS45044A

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.

302401-D Rev 00 C-7