When two routers are connected to communicate using a serial cable connection, one end of the router will be using DTE (Data Terminal Equipment) and the other end uses DCE (Data Communication Equipment). In order to communicate effectively with out any delay or to have the same band width, we use 64000 clock rate.
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Syed
in global configuration mode type this clock rate 64000 and hit enter
Clock rate must be set on an interface that is the DCE. This provides clocking for the DTE and helps with data transmission across the connection.
Data Generating Capability of a Device is called Clock Rate. If the clock rate is high, the processing will be slow down. If the clock rate is low, the processing will be high.
To configure the clock rate for the hardware connections on serial interfaces such as network interface modules (NIMs) and interface processors to an acceptable bit rate, use the clock rate interface configuration command. Use the no form of this command to remove the clock rate if you change the interface from a DCE to a DTE device. Using the no form of this command on a DCE interface sets the clock rate to the hardware-dependent default value.
A clock-rate is the speed at which the Serial connection sends data to another router and each connection must match the others clock-speed or a speed mismatch error will occur. For packet tracer, the clock-rate has no effect.
When the interface is functioning as a DCE device
The interface is configured as a DCE device.
When it needs to provide clocking for the serial line. This occurs when you are using a null-modem cable in a lab. You would apply the clock rate to the router that is connected as the DCE device.
interface serial x/x ip address x.x.x.x x.x.x.x no shut clock rate xxxxxxx end
Clock rate.
Because it is the top operating speed for that IC
The command is: clock rate 56000 So it will appear on the command line interface as: Router(config-if)# clock rate 56000 Reference: Networking by Jeffrey Beasley Chapter 6 page 216.