在DOS命令状态下输入 ：
ping 202.105.135.211 -t (连续的对该IP地址执行Ping命令，直到被用户以Ctrl+C中断)
就会得到下面的结果：
Pinging 202.105.135.211 with 32 bytes of data:
Reply from 202.105.135.211: bytes=32 time=93ms TTL=42
Reply from 202.105.135.211: bytes=32 time=86ms TTL=42
Reply from 202.105.135.211: bytes=32 time=81ms TTL=42
Reply from 202.105.135.211: bytes=32 time=80ms TTL=42
Ping statistics for 202.105.135.211:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 80ms, Maximum = 93ms, Average = 85ms
这里面，丢包率0%,抖动是-5ms到+8ms，延时是 85ms（毫秒），测试另外两个IP地址，可以看到：
Pinging 221.221.23.7 with 32 bytes of data:
Reply from 221.221.23.7: bytes=32 time=28ms TTL=48
Reply from 221.221.23.7: bytes=32 time=26ms TTL=48
Reply from 221.221.23.7: bytes=32 time=26ms TTL=48
Reply from 221.221.23.7: bytes=32 time=26ms TTL=48
Reply from 221.221.23.7: bytes=32 time=28ms TTL=48
Reply from 221.221.23.7: bytes=32 time=28ms TTL=48
Reply from 221.221.23.7: bytes=32 time=27ms TTL=48
Reply from 221.221.23.7: bytes=32 time=60ms TTL=48
Reply from 221.221.23.7: bytes=32 time=113ms TTL=48
Reply from 221.221.23.7: bytes=32 time=27ms TTL=48
Reply from 221.221.23.7: bytes=32 time=52ms TTL=48
Reply from 221.221.23.7: bytes=32 time=58ms TTL=48
Reply from 221.221.23.7: bytes=32 time=27ms TTL=48
Reply from 221.221.23.7: bytes=32 time=112ms TTL=48
Reply from 221.221.23.7: bytes=32 time=76ms TTL=48
Reply from 221.221.23.7: bytes=32 time=154ms TTL=48
Ping statistics for 221.221.23.7:
Packets: Sent = 16, Received = 16, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 26ms, Maximum = 154ms, Average = 54ms
丢包率0%,抖动是-28ms到+100ms，延时是 54ms（毫秒）Pinging 221.221.23.209 with 32 bytes of data:
Reply from 221.221.23.209: bytes=32 time=885ms TTL=48
Reply from 221.221.23.209: bytes=32 time=688ms TTL=48
Reply from 221.221.23.209: bytes=32 time=482ms TTL=48
Reply from 221.221.23.209: bytes=32 time=119ms TTL=48
Reply from 221.221.23.209: bytes=32 time=61ms TTL=48
Reply from 221.221.23.209: bytes=32 time=456ms TTL=48
Reply from 221.221.23.209: bytes=32 time=962ms TTL=48
Reply from 221.221.23.209: bytes=32 time=890ms TTL=48
Reply from 221.221.23.209: bytes=32 time=939ms TTL=48
Reply from 221.221.23.209: bytes=32 time=891ms TTL=48
Reply from 221.221.23.209: bytes=32 time=141ms TTL=48
Reply from 221.221.23.209: bytes=32 time=420ms TTL=48
Reply from 221.221.23.209: bytes=32 time=517ms TTL=48
Reply from 221.221.23.209: bytes=32 time=463ms TTL=48
Reply from 221.221.23.209: bytes=32 time=798ms TTL=48
Reply from 221.221.23.209: bytes=32 time=451ms TTL=48
Reply from 221.221.23.209: bytes=32 time=604ms TTL=48
Ping statistics for 221.221.23.209:
Packets: Sent = 17, Received = 17, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 61ms, Maximum = 962ms, Average = 574ms
丢包率0%,抖动是-511ms到+488ms，延时是 574ms（毫秒）
从上面3个结果看，第一组延时小，第三组延时大。丢包率为0％，只有第一组的网络可以正常使用安装网络电话或视频等保证通话质量，第二组抖动大不可用，第三组延时、抖动都大，也不可用。
根据经验，这3个指标中，任何一个超标，都不可以安装用户端，否则通话质量就没有保障：
丢包率：小于8％
延时：小于200ms
抖动：正负不大于40ms
安装网络电话时，严格把住这些基本指标。用户网络不能达到这些指标，安装以后必然出现话音不好的问题。不达标的IP网络，建议不要安装，等用户网络达标以后再安装，否则给用户和代理商带来许多麻烦。