asp實現限制一個ip只能訪問一次的方法
<%
'/////////////////////////////////////////////////////
'// //
'//作用：一個IP地址只允許訪問本頁一次 //
'//引用：<!-- #include file="Check_Ip.asp" --> //
'// //
'/////////////////////////////////////////////////////
'Response.Charset = 936 '設置輸出編碼為簡體中文
'Response.Buffer = false '關閉緩沖區
Dim Fso,ts,IpList,Cfs
'設置Cookies函數
Function SetCookie()
Response.Cookies("IsBrow") = "Brow"
Response.Cookies("IsBrow").Expires = Date+365
End Function
'記錄IP地址函數
Function WriteIp(FileName, IpAddress)
Set Fso = Server.CreateObject("Scripting.FileSystemObject")
Set ts = Fso.OpenTextFile(Server.MapPath(FileName),8,true)
ts.WriteLine IpAddress
ts.Close
Set ts = NOThing
Set Fso = NOThing
End Function
'讀取IP地址函數
Function ReadIpList(FileName)
Set Fso = Server.CreateObject("Scripting.FileSystemObject")
If Not Fso.FileExists(Server.MapPath(FileName)) Then
CreateFile("Iplist.txt")
Exit Function
End If
Set ts = Fso.OpenTextFile(Server.MapPath(FileName))
Iplist = ts.ReadAll
ts.Close
Set ts = NOThing
Set Fso = NOThing
ReadIpList = Iplist
End Function
'創建文件函數
Function CreateFile(FileName)
Set Fso = Server.CreateObject("Scripting.FileSystemObject")
Set Cfs = Fso.CreateTextFile(Server.MapPath(FileName))
Cfs.Close
Set Cfs = NOThing
Set Fso = NOThing
End Function
'關閉當前IE窗口函數(注:IE6下通過,其他瀏覽器未測試)
Function CloseWindow()
'Response.Write "<script>window.location='javascript:window.opener=null;window.close();'</script>"
Response.Redirect "http://www.baidu.com"
End Function
Ip = Request.ServerVariables("REMOTE_ADDR") '獲取瀏覽者IP地址
Cookie = Request.Cookies("IsBrow") '獲取當前Cookies
'Response.Write Cookie
If Request.ServerVariables("HTTP_X_FORWARDED_FOR") <> "" Then
Response.Write "本站不允許使用代理訪問"
Response.End()
Else
If Cookie = "Brow" Then
CloseWindow()
Else
If Instr(ReadIpList("Iplist.txt"),Ip) <>0 Then
CloseWindow()
Else
WriteIp "Iplist.txt" , Ip
End If
SetCookie()
End If
End If
%>
標簽：
asp
訪問
上傳時間：
2016-07-14
上傳用戶：helei0915
Abstract—In the future communication applications, users
may obtain their messages that have different importance levels
distributively from several available sources, such as distributed
storage or even devices belonging to other users. This
scenario is the best modeled by the multilevel diversity coding
systems (MDCS). To achieve perfect (information-theoretic)
secrecy against wiretap channels, this paper investigates the
fundamental limits on the secure rate region of the asymmetric
MDCS (AMDCS), which include the symmetric case as a special
case. Threshold perfect secrecy is added to the AMDCS model.
The eavesdropper may have access to any one but not more than
one subset of the channels but know NOThing about the sources,
as long as the size of the subset is not above the security level.
The question of whether superposition (source separation) coding
is optimal for such an AMDCS with threshold perfect secrecy
is answered. A class of secure AMDCS (S-AMDCS) with an
arbitrary number of encoders is solved, and it is shown that linear
codes are optimal for this class of instances. However, in contrast
with the secure symmetric MDCS, superposition is shown to
be not optimal for S-AMDCS in general. In addition, necessary
conditions on the existence of a secrecy key are determined as a
design guideline.
標簽：
Fundamental
Limits
Secure
Class
on
of
上傳時間：
2020-01-04
上傳用戶：kddlas
