Cisco Systems IGX 8400 Series Manual De Usuario

3-26 Cisco IGX 8400 Series Installation and Configuration

HDM and LDM Redundancy

Optional redundancy for HDM and LDM cards can be provided with a second front and back card
set and a Y-cable connection on each port to the customer data equipment.

A jumper board comes with an impedance of either 100 ohms or 200 ohms. For higher port

speeds, the impedance is important if you have specified Y-cable redundancy. With Y-cable
redundancy on a higher-speed connection, use the 200-ohm jumper board. With no Y-cable
redundancy or when the port speed is relatively low, the 100-ohm jumper board is adequate.

Configuring the Mode of an LDI Port

Each port on an LDI card uses an adapter cable. For a list of LDI adapter cables, refer to Appendix C,
“Cabling Summary.” Each cable does the following:

•

Determines whether the port operates in DCE mode or DTE mode

•

Connects the port’s 15-pin connector to a 25-pin D connector

•

Converts to either a male or female pinout

See Figure 3-13 for an example. In Figure 3-13, the adapter cable makes the port a DCE port.
Circuits on the card test certain pins on the cable then configure the port as DTE or DCE.

Faceplate

DCE/DTE
jumper board

DCE position

SDI

1 2 3 4 5 6

Faceplate

DCE/DTE
jumper board

DTE position

SDI

1 2 3 4 5 6

H8370