If you connect the patch cord directly to the network cabling, you may need to install a female-to-female adapter
to allow the cables to be connected together.
Figure 28: Connecting a mode conditioning patch cord for Gigabit-LX
Be sure to purchase a patch cord that has appropriate connectors on each end, and has multimode fibers that
match the characteristics of the multimode fiber in your network. Most important, the core diameter of the
multimode patch cord must match the core diameter of the multimode cable infrastructure (either 50 or 62.5
microns).
Twisted-pair cable/connector pinouts
Auto-MDIX feature
In the default configuration, “Auto”, the fixed 10/100/1000BASE-T ports on the Aruba 2930F Switches all
automatically detect the type of port on the connected device and operate as either an MDI or MDI-X port,
whichever is appropriate. So for any connection, a straight-through twisted-pair cable can be used. You no longer
have to use crossover cables, although crossover cables can also be used for any of the connections. (The
10/100/1000-T ports support the IEEE 802.3ab standard, which includes the “Auto-MDIX” feature.)
If you connect a 2930F switch twisted-pair port to another switch or hub, which typically have MDI-X ports, the
2930F port automatically operates as an MDI port. If you connect it to an end node, such as a server or PC, which
typically have MDI ports, the 2930F switch port operates as an MDI-X port. In all cases, you can use standard
straight-through cables or crossover cables.
If you use a correctly-wired crossover cable, though, the switch will still be able to automatically detect the MDI/
MDI-X operation and link correctly to the connected device.
Using fixed configurations
If the port configuration is changed to any of the fixed configurations though, for example 100 Mbps/
full duplex, the port operates as MDI-X only and the correct cable type must be used: for connections
to MDI ports, such as end nodes, use a straight-through cable; for connections to MDI-X ports, such
as on hubs and other switches, use a crossover cable.
Chapter 6 Cabling and technology information
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