Serial port connection between two Routers

Sometimes, when the distance between the subsidiary company and the company is not far from each other, you can directly connect the two routers with serial lines. This method can save the cost of laying optical fiber, but the transmission speed will be affected, and the distance between the two routers must not be too far.
As shown in network topology 1, two vrouters A and B are connected to their S0 ports with A serial line.

Configuration command:
Router
Config t enters Configuration Mode
Int s0 entry S0 Interface
Ip address 192.168.1.1 255.255.255.0 sets the ip address and subnet mask for the S0 Interface
No shutdown enable S0 Port
Clock rate 64000 sets the serial port S0 clock frequency to 64000bit/s.
TIPS: due to the difference between DTE and DCE in Data Communication settings, you must set a clock for the DCE device. Only devices with the same clock frequency can communicate with each other. The unit of clock frequency is bit/s.
Router B
Config t enters Configuration Mode
Int s0 entry S0 Interface
Ip address 192.168.1.2 255.255.255.0 sets the ip address and subnet mask for the S0 Interface
No shutdown enable S0 Port
Clock rate 64000 sets the serial port S0 clock frequency to 64000bit/s.
Conclusion: After the same clock frequency is set and the correct route information is added, the serial ports of the two routers can communicate normally. The parameter bandwidth is also described here. By default, the default serial link bandwidth of any CISCO router is 1.544 Mb/s. You can use the bandwidth command to modify the bandwidth according to the actual situation, for example, bandwidth 64 indicates that the bandwidth is 64000bit/s.