Suppose this simply scenario: 3 SIP phones A,B,C. On B is set a redirection (moved temporarily) direct to C. On C is set a redirection (moved temporarily) direct to B. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> If A calls B and B replies with moved temporarily to C. A INVITE B A ---------a B B “Moved temporarily to C” A s--------- B A calls C and B replies with moved temporarily to B. A INVITE C A ---------a C C “Moved temporarily to B” A s--------- C A calls B A INVITE B A ---------a B so it generates an endless loop. How can I detect and avoid this endless loops? 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? Thanks for your help, Daniele