最近通过vpn的方式链接用户系统来做性能测试，发现性能测试中网速、带宽、网络的稳定性还是很重要的指标，今天特找到测试网速的方法。
命令格式：
ping ip地址 -l 字节数
注：上面的命令中 l 是字母l,不是数字1
网速等于≈(发送的字节数/返回的时间[毫秒])K字节
以上计算的结果速为字节(byte)，不是我们通常说的位(bps)
如：
C:\Documents and Settings\Administrator>ping 202.101.224.68 -l 1000
Pinging 202.101.224.68 with 1000 bytes of data:
Reply from 202.101.224.68: bytes=1000 time=38ms TTL=251
Reply from 202.101.224.68: bytes=1000 time=38ms TTL=251
Reply from 202.101.224.68: bytes=1000 time=38ms TTL=251
Reply from 202.101.224.68: bytes=1000 time=38ms TTL=251
Ping statistics for 202.101.224.68:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 38ms, Maximum = 38ms, Average = 38ms
根据上述发送及返回的信息可以简单得出到地址202.101.224.68的网速为：
网速等于≈(发送的字节数/返回的时间[毫秒])K字节
≈1000/38K字节
≈26.32K字节
附：ping命令帮助说明
C:\Documents and Settings\Administrator>ping /?
Usage: ping [-t] [-a] [-n count] [-l size] [-f] [-i TTL] [-v TOS]
[-r count] [-s count] [[-j host-list] | [-k host-list]]
[-w timeout] [-R] [-S srcaddr] [-4] [-6] target_name
Options:
-t Ping the specified host until stopped.
To see statistics and continue - type Control-Break;
To stop - type Control-C.
-a Resolve addresses to hostnames.
-n count Number of echo requests to send.
-l size Send buffer size.
-f Set Don't Fragment flag in packet (IPv4-only).
-i TTL Time To Live.
-v TOS Type Of Service (IPv4-only).
-r count Record route for count hops (IPv4-only).
-s count Timestamp for count hops (IPv4-only).
-j host-list Loose source route along host-list (IPv4-only).
-k host-list Strict source route along host-list (IPv4-only).
-w timeout Timeout in milliseconds to wait for each reply.
-R Trace round-trip path (IPv6-only).
-S srcaddr Source address to use (IPv6-only).
-4 Force using IPv4.
-6 Force using IPv6.
C:\Documents and Settings\Administrator
