实验内容：
R1：机房设备，R2、R3模拟PC进行远程登陆R1，配置telnet两种认证方式
实验步骤：
1.使用ensp建立拓扑。
2.配置各设备端口ip地址：
<Huawei>sys
Enter system view, return user view with Ctrl+Z.
[Huawei]sys R1
[R1]INT G0/0/0
[R1-GigabitEthernet0/0/0]IP ADDR 10.1.1.254 24
<Huawei>SYS
Enter system view, return user view with Ctrl+Z.
[Huawei]SYS R2
[R2]INT G0/0/0
[R2-GigabitEthernet0/0/0]IP ADDR 10.1.1.1 24
------------------------------------------------------------------------------------------------
<Huawei>SYS
Enter system view, return user view with Ctrl+Z.
[Huawei]SYS R3
[R3]INT G0/0/0
[R3-GigabitEthernet0/0/0]IP ADDR 10.1.1.2 24
################################################################
3.配置password认证
R1上配置telnet 验证方式为密码验证方式，密码为huawei，并设置密文存储，
[R1]user-interface vty 0 4
[R1-ui-vty0-4]authentication-mode password ***
Please configure the login password (maximum length 16):huawei ***
-----------------------------------------------------
<R2>telnet 10.1.1.254
*** Press CTRL_] to quit telnet mode
*** Trying 10.1.1.254 ...
*** Connected to 10.1.1.254 ...***
Login authentication
Password:
<R1>
###############################################################
4.配置aaa认证
***[R1]aaa ***
[R1-aaa]local-user admin password cipher hello privilege level 3 //添加admin账户密码为hello，密文保存，用户权限3
[R1-aaa]local-user admin service-type telnet
[R1-aaa]q
***[R1]user-interface vty 0 4 ***
***[R1-ui-vty0-4]authentication-mode aaa ***
***###############################################################*********
