2.2 Console port configuration
The console and auxiliary ports on Cisco IOS® routers are asynchronous serial ports. The console port and the auxiliary port are configured as data terminal equipment (DTE). 2500, 2600, and 3600 Series Routers use RJ-45 connectors on both console and auxiliary ports. You need to use appropriate adapter to connect to the external console or modem as required.
This table shows the console port configuration for the RJ-45 connector
| Console Port(DTE) | RJ-45 to DB-25 Terminal Adapter | Console Device | |
| RTS | 1 | 5 | CTS |
| DTR | 2 | 6 (8?) | DSR |
| TxD | 3 | 3 | RxD |
| GND | 4 | 7 | GND |
| RxD | 6 | 2 | TxD |
| DSR | 7 | 20 | DTR |
| CTS | 8 | 4 | RTS |
