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<TITLE>Re: [Freeswitch-users] optional SRTP</TITLE>
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<FONT FACE="Monaco, Courier New"><SPAN STYLE='font-size:11pt'>FreeSWITCH Support SIP/TLS, SRTP and ZRTP, the error message you are refering to below is where someone has improperly implemented SRTP and is sending the crypto headers in the wrong spots. See the Wiki for setting up secure calling.<BR>
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Also please note, if you are going to use SRTP, you _must_ use SIP/TLS as the keys for SRTP are passed in the SDP of the SIP messaging. You can use ZRTP without using SIP/TLS as the key exchange for ZRTP happens as a DH exchange in the ZRTP stream, but if you want to protect the contents of the SIP messaging you’ll still want to use SIP/TLS.<BR>
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K<BR>
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On 2/22/13 9:36 AM, "Levend Sayar" <<a href="levend.sayar@karel.com.tr">levend.sayar@karel.com.tr</a>> wrote:<BR>
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</SPAN></FONT><BLOCKQUOTE><FONT FACE="Monaco, Courier New"><SPAN STYLE='font-size:11pt'>Hi again.<BR>
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On my previous discussion on this list, i learned that RTP/AVP with a a=crypto attribute means optional SRTP.<BR>
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I suppose FS supports optional SRTP, but when i look at the sofia code, afaiu fs does not support it.<BR>
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Right ?<BR>
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A code snippet from sofia_glue.c <BR>
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if (m->m_proto != sdp_proto_srtp) {<BR>
switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "a=crypto in RTP/AVP, refer to rfc3711\n");<BR>
match = 0;<BR>
goto done;<BR>
}<BR>
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-- <BR>
Ken<BR>
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