Cisco C1861-SRST-B/K9 Hardware Installation Guide - Page 48

Connecting to a Console Terminal or Modem Chapter 4 Power, Cable, and Antenna Connection Procedures Table 4-3 Port Console Auxiliary • One console cable (RJ-45-to-DB-9, blue) • One DB-9-to-DB-25 adapter This section describes how to connect a console terminal or PC to the console port and how to connect a modem to the auxiliary port. Table 4-3 summarizes the system management connections. System Management Connections Color Connected Device Light blue PC or ASCII terminal communication port (usually labeled COM) Black Modem for remote access Cable RJ-45-to-DB-9 console cable RJ-45-to-DB-9 console cable with a DB-9-to-DB25 adapter For information about cable pinouts, see the Cisco Modular Access Router Cable Specifications document. Warning To avoid electric shock, do not connect safety extra-low voltage (SELV) circuits to telephone-network voltage (TNV) circuits. LAN ports contain SELV circuits, and WAN ports contain TNV circuits. Some LAN and WAN ports both use RJ-45 connectors. Use caution when connecting cables. Statement 1021 Warning Hazardous network voltages are present in WAN ports regardless of whether power to the unit is OFF or ON. To avoid electric shock, use caution when working near WAN ports. When detaching cables, detach the end away from the unit first. Statement 1026 Warning Before opening the unit, disconnect the telephone-network cables to avoid contact with telephone-network voltages. Statement 1041 Console and Auxiliary Port Considerations The router includes an asynchronous serial console port and an auxiliary port. The console and auxiliary ports provide access to the router either locally (using a console terminal connected to the console port) or remotely (using a modem connected to the auxiliary port). This section provides important information about cabling that you should consider before you connect the router to a console terminal or a modem. The main difference between the console port and the auxiliary port is that the auxiliary port supports hardware flow control and the console port does not. Flow control paces the transmission of data between a sending device and a receiving device. Flow control ensures that the receiving device can absorb the data sent to it before the sending device sends more. When the buffers on the receiving device are full, a message is sent to the sending device to suspend transmission until the data in the buffers has been processed. Because the auxiliary port supports flow control, it is ideally suited for use with the high-speed transmissions of a modem. Because console terminals send data at slower speeds than modems, the console port is ideally suited for use with console terminals. Cisco 1800 Series Integrated Services Routers (Fixed) Hardware Installation Guide 4-6 OL-6425-03