1、可以根据
MAC地址判断或者MAC+IP+计算机名。
2、直接用客户端脚本，我们这里用Javascript，这样做的好处是不需要服务器端进行处理，有客户端自行获取，传递到服务器端，且速度和可靠性都比在服务器
端获取好。
追问怎么用Javascript获取mac地址呢
追答<SCRIPT language=JScript event="OnCompleted(hResult,pErrorObject, pAsyncContext)" for=foo> document.forms[0].txtMACAddr.value=unescape(MACAddr);
document.forms[0].txtIPAddr.value=unescape(IPAddr);
document.forms[0].txtDNSName.value=unescape(sDNSName);
//document.formbar.submit();
</SCRIPT>
<SCRIPT language=JScript event=OnObjectReady(objObject,objAsyncContext) for=foo>
if(objObject.IPEnabled != null && objObject.IPEnabled != "undefined" && objObject.IPEnabled == true)
{
if(objObject.MACAddress != null && objObject.MACAddress != "undefined")
MACAddr = objObject.MACAddress;
if(objObject.IPEnabled && objObject.IPAddress(0) != null && objObject.IPAddress(0) != "undefined")
IPAddr = objObject.IPAddress(0);
if(objObject.DNSHostName != null && objObject.DNSHostName != "undefined")
sDNSName = objObject.DNSHostName;
}
</SCRIPT>
代码超了，你再追问，我把剩下的代码附带回答。
追问只在ie中有效么？
追答<META content="MSHTML 6.00.2800.1106" name=GENERATOR></HEAD> <BODY>
<OBJECT id=locator classid=CLSID:76A64158-CB41-11D1-8B02-00600806D9B6 VIEWASTEXT></OBJECT>
<OBJECT id=foo classid=CLSID:75718C9A-F029-11d1-A1AC-00C04FB6C223></OBJECT>
<SCRIPT language=JScript>
var service = locator.ConnectServer();
var MACAddr ;
var IPAddr ;
var DomainAddr;
var sDNSName;
service.Security_.ImpersonationLevel=3;
service.InstancesOfAsync(foo, 'Win32_NetworkAdapterConfiguration');
</SCRIPT>
<FORM id=formfoo name=formbar action=NICPost.asp method=post><INPUT value=00:05:5D:0E:C7:FA name=txtMACAddr> <INPUT value=192.168.0.2 name=txtIPAddr> <INPUT value=typ name=txtDNSName> </FORM></BODY></HTML>
关键是用到两个ActiveX：
<OBJECT id=locator classid=CLSID:76A64158-CB41-11D1-8B02-00600806D9B6 VIEWASTEXT></OBJECT>
<OBJECT id=foo classid=CLSID:75718C9A-F029-11d1-A1AC-00C04FB6C223></OBJECT>