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<DIV><FONT face=Verdana color=#000000 size=2>Hi, I have noticed that some SIP system are using the "From:" header field domain/IP to authenticate or do some routing operation instead of the sending IP address.</FONT></DIV>
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<DIV><FONT face=Verdana color=#000000 size=2>If they authenticate only on the "From:" header field, I guess they could be vulnarable to spoofing.</FONT></DIV>
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<DIV><FONT face=Verdana><FONT size=2>Anyhow, I am wandering if we should replace the From </FONT> <FONT size=2>header field IP address with the one of the SIP proxy even if this is not RFC recommended for a proxy ?</FONT></FONT></DIV>
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