Eliminates the need for a rollover cable or a Cisco console cable. Just use any straight-through Ethernet cable.

In adapter kits, the RJ-45 side of the wires are attached. Plug them into the DB-9 side in the following order:

RJ-45      wire       Serial

1 (RTS)   blue      8 (CTS)
2 (DTR)  orange  6 (DSR)
3 (TxD)   black    2 (RxD)
4 (Gnd)   red        (Unused)
5 (Gnd)   green    5 (Gnd)
6 (RxD)  yellow  3 (TxD)
7 (DSR)  brown   4 (DTR)
8 (CTS)  grey       7 (RTS)

RJ-45 side is the DTE pinout of the Console port of most common Cisco equipment.