I have a customer installation with an Adtran DS3 mux. The DS1's go into my Asterisk servers that run IVR/Call recorders. The DS3 provider is Qwest, and they tell me that they routinely drop the DS3 service to redundant back-up's and that this is a common practice that happens thousands of times to DS3 lines daily across the US without any service interruptions. They say that the switchover time is covered by specification, AND my Adtran mux. I've modified the zaptel drivers to mask out hardware alarms (alarmdebounce) with no success. I think that I have weeded out all poss ability of alarm conditions coming from the physical T1 framers, and I still get #6 and #8 HDLC PRI errors that are dropping all calls on the servers. I've been working on this for about 6 months now, and I can't be live that all asterisk PRI installations are dropping all calls at a rate of 2 per month like I am. Everything appears to be in spec. The carrier gave me several example installations that are not dropping calls but they are not using Asterisk. They all were using my Adtran mux though. I have 3 Adtran muxes and have tried them all. I have used different T1 cards. The results are all the same. 2 times a month, all of the calls are dropped. I get a page when this happens, and then some times another from my customer who gets an e-mail about a call that was lost. I'm starting to think that this installation is unique in its size and that this is just a byproduct of free software, but I never see this behavior in any smaller installations. I think that my best bet is that someone here knows how to manipulate the q931 to not drop the calls or somehow stop the errors from dropping the calls. Thanks, Bob
That is the back-up we are talking about here, the call loss is %100 when this happens. ---- Alex Balashov <abalashov at evaristesys.com> wrote:> > I think one critical aspect to explore here is, what exactly is meant by > "drop the DS3 service to redundant back-ups"? > > SONET protection switching inside their transport core should not impact > your DS3s or voice-bearing T1s if it is within the 50 ms tolerance of > the standard. I imagine some SONET line equipment even jitter-buffers > to account for this sort of thing, although that is speculation. > > Or is there another form of "back-up" involved? What is it? > > -- > Alex Balashov > Evariste Systems > Web : http://www.evaristesys.com/ > Tel : +1-678-954-0670 > Direct : +1-678-954-0671 > > _______________________________________________ > --Bandwidth and Colocation Provided by http://www.api-digital.com-- > > asterisk-users mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users
I think one critical aspect to explore here is, what exactly is meant by "drop the DS3 service to redundant back-ups"? SONET protection switching inside their transport core should not impact your DS3s or voice-bearing T1s if it is within the 50 ms tolerance of the standard. I imagine some SONET line equipment even jitter-buffers to account for this sort of thing, although that is speculation. Or is there another form of "back-up" involved? What is it? -- Alex Balashov Evariste Systems Web : http://www.evaristesys.com/ Tel : +1-678-954-0670 Direct : +1-678-954-0671
I'm battling from a position here where I don't have a different DS3 to play with, and I don't have a differnet mux. I'm being leaned on completely with the argument that everyone else does this without any service interruptions. I'm asking this group for the secret. I have run out of arguments about the service and the switchover. Like I said, I've been looking at this for 6 months now. ---- Alex Balashov <abalashov at evaristesys.com> wrote:> On Thu, 2 Aug 2007, bob_is_me at cox.net wrote: > > > That is the back-up we are talking about here, the call loss is %100 > > when this happens. > > Ah, I see. So, if I understand you correctly, what you appear to be > saying is that somewhere between your Asterisk box and your Adtran mux > this is not being handled gracefully. > > From where do you have the impression it would be any different if you > had a different M13 mux or weren't using a PC-based open-source TDM > platform? > > -- > Alex Balashov > Evariste Systems > Web : http://www.evaristesys.com/ > Tel : +1-678-954-0670 > Direct : +1-678-954-0671 > > _______________________________________________ > --Bandwidth and Colocation Provided by http://www.api-digital.com-- > > asterisk-users mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users
Can someone here tell me why a switchover at the SONET level CAN disturb my DS1? From the beginning, I though that carrier and messages were contained in this specification. ---- Alex Balashov <abalashov at evaristesys.com> wrote:> On Thu, 2 Aug 2007, bob_is_me at cox.net wrote: > > > That is the back-up we are talking about here, the call loss is %100 > > when this happens. > > Ah, I see. So, if I understand you correctly, what you appear to be > saying is that somewhere between your Asterisk box and your Adtran mux > this is not being handled gracefully. > > From where do you have the impression it would be any different if you > had a different M13 mux or weren't using a PC-based open-source TDM > platform? > > -- > Alex Balashov > Evariste Systems > Web : http://www.evaristesys.com/ > Tel : +1-678-954-0670 > Direct : +1-678-954-0671 > > _______________________________________________ > --Bandwidth and Colocation Provided by http://www.api-digital.com-- > > asterisk-users mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users