R3
[R3]aaa
[R3-aaa]local-user huawei password cipher huawei123
[R3-aaa]local-user huawei service-type ppp
[R3-Serial0/0/1]link-protocol ppp
[R3-Serial0/0/1]ppp chap user huawei
[R3-Serial0/0/1]ppp chap password cipher huawei123
R4
[Huawei]sy R4
[R4]int s0/0/1
[R4-Serial0/0/1]ip ad 10.1.1.2 30
[R4-Serial0/0/1]link-protocol ppp
[R4-Serial0/0/1]ppp chap user huawei
[R4-Serial0/0/1]ppp chap password cipher huawei123
