目的：对192.168.57.0段用户限速30M（即下载速度30/8，上传同），192.168.57.1和192.168.57.127除外
access-list rate-limiting extended deny ip any 192.168.57.1 255.255.255.255
access-list rate-limiting extended deny ip 192.168.57.1 255.255.255.255 any
access-list rate-limiting extended deny ip any 192.168.57.127 255.255.255.255
access-list rate-limiting extended deny ip 192.168.57.127 255.255.255.255 any
access-list rate-limiting extended permit ip 192.168.57.0 255.255.255.0 any
access-list rate-limiting extended permit ip any 192.168.57.0 255.255.255.0
class-map rate-limiting
match access-list rate-limiting
policy-map xs10m
class rate-limiting
police input 30000000
police output 30000000
!
service-policy xs10m interface inside //应用在inside口。在outside应用时不生效，因nat的应用，使得内外网IP不是一一对应，不法正常限制。
原文：http://sunrc.blog.51cto.com/747991/1953293