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For an Asterisk-environment with no more then 10 SIP-phones, I would open 10 x 4 = 40 UDP ports for RTP/RTCP-traffic ( 4/call). Can you confirm ?!<BR>
rtp.conf : <BR>
<B><FONT SIZE="2"><FONT COLOR="#000000">rtpstart=</FONT></FONT></B><B><FONT SIZE="2">3</FONT></B><B><FONT SIZE="2"><FONT COLOR="#000000">0</FONT></FONT></B><B><FONT SIZE="2">5</FONT></B><B><FONT SIZE="2"><FONT COLOR="#000000">00</FONT></FONT></B><BR>
<B><FONT SIZE="2"><FONT COLOR="#000000">rtpend=</FONT></FONT></B><B><FONT SIZE="2">3</FONT></B><B><FONT SIZE="2"><FONT COLOR="#000000">0</FONT></FONT></B><B><FONT SIZE="2">55</FONT></B><B><FONT SIZE="2"><FONT COLOR="#000000">0</FONT></FONT></B><BR>
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Ok, there's 50 here... a round number right ?!<BR>
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All SIP-communication stays on the LAN. There's a NIC connected on the switch.<BR>
Another NIC (WAN) is used for IAX-traffic to a VoIP-provider.<BR>
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So, I do not really need to worry about security flaws ?! Except if hackers are able to hack another server on the network, than these ports are open for them...<BR>
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On the firewall there's just port 4569 (IAX) that's forwarded to the WAN-interface of the Asterisk-server.<BR>
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A little second question : by defining a default route via the WAN-interface, traffic that needs to leave the network will be routed to the VoIP-provider ?<BR>
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So all internal communication goes via the LAN-interface. All the traffic that needs to go to the default gateway is defined in my route table to leave the Asterisk-server via the WAN-interface.<BR>
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There are no more options I need to configure in Asterisk ???<BR>
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Asterisk works on OSI-level 'application', so traffic is not routed by Asterisk. When Asterisk needs to send SIP-messages or RTP-traffic to an IP-adres that is not on the local LAN, OSI-layer 3 (IP network) will route it via the correct interface.<BR>
Asterisk will translate from SIP to IAX, but routing between interface 1 (LAN) and interface 2 (WAN) will happen much lower on the OSI-model.<BR>
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Am I right ? Or do I need some special settings in Asterisk (sip.conf or iax.conf) to be able to route between internal and exteral NIC.<BR>
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Thanks for the info on RTP-ports and my routing-question.<BR>
<BR>
Jonas.
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