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<BODY bgColor=#ffffff><FONT face=Arial><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB"><FONT size=2><FONT color=#0000ff>Suppose this
simply scenario: 3 SIP phones A,B,C.<BR></FONT></FONT></SPAN><FONT size=2><FONT
color=#0000ff><SPAN lang=EN-GB style="mso-ansi-language: EN-GB">On B is set a
redirection (moved temporarily) direct to C. <BR></SPAN></FONT><FONT
color=#0000ff><SPAN lang=EN-GB style="mso-ansi-language: EN-GB">On C is set a
redirection (moved temporarily) direct to B. <?xml:namespace prefix = o ns =
"urn:schemas-microsoft-com:office:office" /><o:p></o:p></SPAN></FONT></FONT>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB"> </SPAN></FONT></FONT><FONT size=2><FONT
color=#0000ff><SPAN lang=EN-GB style="mso-ansi-language: EN-GB">If A calls B and
B replies with moved temporarily to C.<o:p></o:p></SPAN></FONT></FONT></P>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff>A<SPAN
style="mso-spacerun: yes"> </SPAN>INVITE B<BR><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB">A ---------</SPAN><FONT face=Arial><SPAN
lang=EN-GB
style="FONT-FAMILY: Wingdings; mso-ansi-language: EN-GB; mso-ascii-font-family: 'Nimbus Roman'; mso-hansi-font-family: 'Nimbus Roman'; mso-char-type: symbol; mso-symbol-font-family: Wingdings"><SPAN
style="mso-char-type: symbol; mso-symbol-font-family: Wingdings">à</SPAN></SPAN><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB">
B<o:p></o:p></SPAN></FONT></FONT></FONT></P>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB">B<SPAN style="mso-spacerun: yes">
</SPAN>“Moved temporarily to C”<BR></SPAN><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB">A </SPAN><FONT face=Arial><SPAN lang=EN-GB
style="FONT-FAMILY: Wingdings; mso-ansi-language: EN-GB; mso-ascii-font-family: 'Nimbus Roman'; mso-hansi-font-family: 'Nimbus Roman'; mso-char-type: symbol; mso-symbol-font-family: Wingdings"><SPAN
style="mso-char-type: symbol; mso-symbol-font-family: Wingdings">ß</SPAN></SPAN><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB">--------- B<SPAN
style="mso-tab-count: 1"> </SPAN><o:p></o:p></SPAN></FONT></FONT></FONT></P>
<P class=MsoNormal><SPAN lang=EN-GB style="mso-ansi-language: EN-GB"><BR><FONT
size=2><FONT color=#0000ff>A calls C and B replies with moved temporarily to
B.<o:p></o:p></FONT></FONT></SPAN></P>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff><SPAN
style="mso-spacerun: yes"><SPAN class=191243008-18062004>A</SPAN>
</SPAN>INVITE C</FONT><BR><FONT color=#0000ff>A ---------<SPAN lang=EN-GB
style="FONT-FAMILY: Wingdings; mso-ansi-language: EN-GB; mso-ascii-font-family: 'Nimbus Roman'; mso-hansi-font-family: 'Nimbus Roman'; mso-char-type: symbol; mso-symbol-font-family: Wingdings"><SPAN
style="mso-char-type: symbol; mso-symbol-font-family: Wingdings">à</SPAN></SPAN>
C</FONT></FONT></P>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB">C<SPAN style="mso-spacerun: yes">
</SPAN>“Moved temporarily to B”<BR></SPAN></FONT><FONT color=#0000ff><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB">A </SPAN><FONT face=Arial><SPAN
lang=EN-GB
style="FONT-FAMILY: Wingdings; mso-ansi-language: EN-GB; mso-ascii-font-family: 'Nimbus Roman'; mso-hansi-font-family: 'Nimbus Roman'; mso-char-type: symbol; mso-symbol-font-family: Wingdings"><SPAN
style="mso-char-type: symbol; mso-symbol-font-family: Wingdings">ß</SPAN></SPAN><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB">---------
C<o:p></o:p></SPAN></FONT></FONT></FONT></P>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB">A calls B <BR></SPAN></FONT><FONT
color=#0000ff></FONT><FONT size=2>A<SPAN style="mso-spacerun: yes">
</SPAN>INVITE B<BR><SPAN lang=EN-GB style="mso-ansi-language: EN-GB"><SPAN
class=191243008-18062004>A </SPAN> ---------</SPAN><FONT
face=Arial><SPAN lang=EN-GB
style="FONT-FAMILY: Wingdings; mso-ansi-language: EN-GB; mso-ascii-font-family: 'Nimbus Roman'; mso-hansi-font-family: 'Nimbus Roman'; mso-char-type: symbol; mso-symbol-font-family: Wingdings"><SPAN
style="mso-char-type: symbol; mso-symbol-font-family: Wingdings">à</SPAN></SPAN><SPAN
lang=EN-GB style="mso-ansi-language: EN-GB">
B<o:p></o:p></SPAN></FONT></FONT></FONT></P>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff>so <SPAN
class=191243008-18062004>it </SPAN>generates an endless loop<SPAN
class=191243008-18062004>.</SPAN> <o:p></o:p></FONT></FONT></P>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB">How can I detect and avoid this endless
loops?<o:p></o:p></SPAN></FONT></FONT></P>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB">Does the INVITE contain an header field,
analogous to the “Max Forwards”, that I can see to identify a loop and
consequently refuse the INVITE?</SPAN></FONT></FONT></P><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB"><SPAN class=191243008-18062004>
<P><FONT size=2><FONT color=#0000ff>Thanks for your help<SPAN
class=191243008-18062004>, </SPAN></FONT></FONT></P></SPAN></SPAN>
<P class=MsoNormal><FONT size=2><FONT color=#0000ff><SPAN lang=EN-GB
style="mso-ansi-language: EN-GB"><SPAN
class=191243008-18062004>Daniele </SPAN><o:p></o:p></SPAN></FONT></FONT></P></FONT></BODY></HTML>