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<TITLE>RE: On TD26 - Fast TCS and M/S negotiation in H.323v4</TITLE>
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<P><FONT SIZE=2>> Paul,</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> We agreed at the Osaka meeting to allow a SETUP to contain both the</FONT>
<BR><FONT SIZE=2>> fastStart and h245Control, but it has not been officially </FONT>
<BR><FONT SIZE=2>> approved by the</FONT>
<BR><FONT SIZE=2>> ITU.</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> As it stands right now, I don't think I can agree to include </FONT>
<BR><FONT SIZE=2>> it in H.323v4</FONT>
<BR><FONT SIZE=2>> on the grounds that it breaks backward compatibility with </FONT>
<BR><FONT SIZE=2>> V2-- I just don't</FONT>
<BR><FONT SIZE=2>> see a clean solution here.</FONT>
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<P><FONT SIZE=2>It doesn't "break" anything. The call will still proceed.</FONT>
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<P><FONT SIZE=2>> I'm opening to hearing more suggestions, but as you pointed </FONT>
<BR><FONT SIZE=2>> out, there are</FONT>
<BR><FONT SIZE=2>> two issues:</FONT>
<BR><FONT SIZE=2>> 1) H.323v2 states explicitly that it is illegal</FONT>
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<P><FONT SIZE=2>There are a lot of things that changed from v2 to v4. That's the role of </FONT>
<BR><FONT SIZE=2>versions.</FONT>
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<P><FONT SIZE=2>> 2) There is no way to know what version to destination EP is before</FONT>
<BR><FONT SIZE=2>> sending this illegal message</FONT>
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<P><FONT SIZE=2>That would apply to any single change that we do on H.225.0 and H.245.</FONT>
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