IOS中的banner命令用来设置提示信息，比如警告未授权的登录、提示当前登录的设备等等，有以下几种：
router(config)#banner ?
LINE c banner-text c, where 'c' is a delimiting character
config-save Set message for saving configuration
exec Set EXEC process creation banner
incoming Set incoming terminal line banner
login Set login banner
motd Set Message of the Day banner
prompt-timeout Set Message for login authentication timeout
slip-ppp Set Message for SLIP/PPP
为了更好的理解这几种banner的区别，通过下面实例来说明：
router(config)#banner incoming # it's incoming # // 设置反向telnet的提示信息
router(config)#banner login # it's login # // 设置login的提示信息
router(config)#banner motd # it's motd # // 设置motd的提示信息
router(config)#banner prompt-timeout # it's prompt-timeout # // 设置prompt-timeout的提示信息
下面通过telnet登录这台路由器进行验证
C:\Documents and Settings\Administrator>telnet x.x.x.x
it's motd message//这是motd的提示信息，后面跟着login的提示信息
User Access Verification
Password: it's prompt-timeout //如果一直不输入密码，将会给出超时的banner message
Password: //输入正确密码
it's exec // 这是登录成功后的banner message
值得注意的是：各种banner不要使用"welcome"字眼，避免未经授权的登陆者感觉受到挑衅，或者通过法律途径"规避"责任。
**********************************************************************************
* *
* WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! *
* You are connected to the XXXXXXXXXXXXXXXXXXXXXXXX incorporated network. *
* Unauthorized access and use of this network will be vigorously prosecuted. *
* CISCO 2960-1 IP Address:x.x.x.x *
* *
**********************************************************************************
