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<p class=MsoNormal>Hello,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’m looking for some advice on securing Asterisk.<o:p></o:p></p>
<p class=MsoNormal>Recently my servers been under several brute-force SIP
attacks.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I have several remote sites, as well as many roaming users,
who may have PC softclients and/or SIP based hardphones.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>My first step will be to strengthen the passwords in use,
and for the hardphones to restrict by IP address, but that still leaves the
softphone quite widely open.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Does Asterisk 1.6 have anything in it that can automatically
block out an attacking IP, say if it receives several 20 or so failed attempts
from that IP in x minutes?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I haven’t looked at Secure SIP in quite a while, is
that now integrated into 1.6 ?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>One thing that’s confusing me in my config, is
that I thought that if I set NAT=no in sip.conf, then I wouldn’t be able
to connect to that SIP account unless I was on the local LAN, specified by locallan=
However in some testing, I’m finding that I can still connect from
an external SIP client.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Also, I tried setting one SIP account from host=dynamic to
host=<ipaddr>, and when that client tried to register, then Asterisk
complained that the account wasn’t supposed to be trying to register.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>My next step is also to upgrade my Asterisk itself up to the
latest stable 1.6<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Any other suggestions?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span lang=EN-US>Thanks,<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Adrian<o:p></o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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