Michael Jerris napsal(a):
On Apr 7, 2008, at 3:45 AM, kokoska rokoska wrote:
We already kill the call if the Max-Forwards makes it to zero.
No, unfotunately, Max-Forwards is not for the same thing. X-HopCounter we (I and lot of VoIP providers around me) use for overall "hops" (visited call-routers) counting - ISUP and SIP. This variable comes from SS7 world (ISUP) and is mandatory for good interconnection (helps against loops etc. - similary as MaxForwards does) especialy if RNPDB comes into the game :-) First router sets HopCounter to 31, every next router should decrement the value on every single processing attempt (i.e. if call goes thru 5 extensions in Freeswitch dialplan it should be decremented by 5) and on 0 or lower values router should stop routing and reject the call...
I think we would probably convert this to a Max-Forwards when doing a sip interconnect, I need to see if we decrement it in a transfer within the switch, I believe we already do. But like all the other headers, we can get it with variables, and create the other header, but we only auto decrement the Max-Forwards. That being said, it is not required that we start Max-Forwards at 70. I have in the past passed this along from ss7 by either passing the value directly from ss7 or using a ratio calculation similar to how cisco does it.
Mike
Thank you very much, Michael, for your comment! Converting HopCounter to Max-Forwards may do the job, but I still need to append special header X-HopCounter, because operators look for it. But i can simply "copy" content of Max-Forwards or do the math by myself :-) Regards, kokoska.rokoska