之前有介绍Linux下通过iptables限制UDP发包，这次记录下Windows 2003的实现方法。
新建bat脚本，添加以下内容，然后点击运行。
:Created by https://www.jb51.net
:DROP UDP Flood
@echo off
cls
:获取DNS地址
for /f "delims=: tokens=1,2" %%a in ('ipconfig /all ^|findstr /i "DNS Server"') do (
set DNSIP=%%b
)
:新建IP安装策略禁止UDP
netsh ipsec static add policy name=禁止UDP description=允许DNS，拒绝其它UDP外出
:新建IP安全规则
netsh ipsec static add filterlist name=允许UDP
netsh ipsec static add filterlist name=拒绝UDP
:新建IP筛选器
netsh ipsec static add filter filterlist=允许UDP srcaddr=me dstaddr=%DNSIP% description=允许DNS查询 protocol=udp mirrored=yes dstport=53
netsh ipsec static add filter filterlist=拒绝UDP srcaddr=me dstaddr=any description=禁止UDP外出 protocol=udp mirrored=yes
:新建IP筛选器操作
netsh ipsec static add filteraction name=允许DNS查询 action=permit
netsh ipsec static add filteraction name=拒绝UDP外出 action=block
:封装策略
netsh ipsec static add rule name=允许规则 policy=禁止UDP filterlist=允许UDP filteraction=允许DNS查询
netsh ipsec static add rule name=拒绝规则 policy=禁止UDP filterlist=拒绝UDP filteraction=拒绝UDP外出
:应用IP安全策略
netsh ipsec static set policy name=禁止UDP assign=y