I know the subject of faxing has been covered in some detail, but I was wondering if anyone has a hardware configuration similar to ours that has faxes working successfully and would be willing to share any settings/insight. We are unable to fax reliably with a Sipura 2100 connected to Asterisk. We do not route calls over the Internet and our network has very low latency. The Asterisk servers connect to Cisco Routers that have PRIs from various carriers. We have all the recommended settings in the Sipura ATA, with Echo Cancellation and Silence Suppression off, uLaw only for the codec, etc. While I realize that no faxes going through passthrough like this will work 100% of the time, we currently have a less than 40% success rate with inbound faxes being the worst. Any insight anyone has would be greatly appreciated! Best Regards, -- Darrell S. Long BestWeb Corporation
This is what I set on my Sipura: You have to be in as admin and then advanced settings. On the SIP page change: RTP Packet Size: 0.010 On the Line Page: FAX CED Detect Enable: Yes FAX CNG Detect Enable: Yes FAX Passthru Codec: G711u FAX Codec Symmetric: No FAX Passthru Method: NSE FAX Process NSE: Yes Release Unused Codec: Yes Click Submit All Changes Have not had 1 dropped fax. On 1/5/06, Darrell Long <dlong@bestweb.net> wrote:> I know the subject of faxing has been covered in some detail, but I was > wondering if anyone has a hardware configuration similar to ours that > has faxes working successfully and would be willing to share any > settings/insight. > > We are unable to fax reliably with a Sipura 2100 connected to Asterisk. > We do not route calls over the Internet and our network has very low > latency. The Asterisk servers connect to Cisco Routers that have PRIs > from various carriers. We have all the recommended settings in the > Sipura ATA, with Echo Cancellation and Silence Suppression off, uLaw > only for the codec, etc. > > While I realize that no faxes going through passthrough like this will > work 100% of the time, we currently have a less than 40% success rate > with inbound faxes being the worst. > > Any insight anyone has would be greatly appreciated! > > Best Regards, > > -- > Darrell S. Long > BestWeb Corporation > > > _______________________________________________ > --Bandwidth and Colocation provided by Easynews.com -- > > Asterisk-Users mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users >-- Tom Vile Baldwin Technology Solutions, Inc Consulting - Web Design - VoIP Telephony www.baldwintechsolutions.com Phone: 518-631-2855 x205 Fax: 518-631-2856
I tried to get it working for a very long time (over a year) with every possible set of config parameters I could find both for * as well as for the Sipura's. Echo cancelling etc. etc. all changed but still problems. I tried to get it working on an * box with a BRI line. Finally I have given up and attached a traditional ISDN -> Analog (A/B) converter to the ISDN line for the faxing bit next to Asterisk. I have yet to find a similar solution for faxing with a PRI, I'm afraid it will be impossible because as far as I know it's not possible to hook up some sort of A/B adapter next to the * box on one pri line. I think it can work if your fax machines are capable of capping fax tx/rx speeds to 9600 baud maximum without error correction. However it seems that not a single producer of FAX equipment (be it modems, all-in-one devices or even dedicated fax machines) offer such an option. HP doesn't seem very interested in capping the fax speeds for their all-in-one thingies. All fax products keep trying to transmit/receive at higher speeds after which the fax will fail completely or after the second page. Maybe there is a solution coming for PRI faxing. Junghanns informed me some time ago that they were working on a PRI card with a possibility to sync the clock to other cards. If this works in theory you could use a Junghanns PRI card and a Junghanns BRI card, sync the clocks and keep the path fully digital without lost frames. On their website however they only mention the possibility to interconnect the PRI cards, not (yet?) PRI <-> BRI. On Thu, 5 Jan 2006, Darrell Long wrote:> I know the subject of faxing has been covered in some detail, but I was > wondering if anyone has a hardware configuration similar to ours that has > faxes working successfully and would be willing to share any > settings/insight. > > We are unable to fax reliably with a Sipura 2100 connected to Asterisk. We do > not route calls over the Internet and our network has very low latency. The > Asterisk servers connect to Cisco Routers that have PRIs from various > carriers. We have all the recommended settings in the Sipura ATA, with Echo > Cancellation and Silence Suppression off, uLaw only for the codec, etc. > > While I realize that no faxes going through passthrough like this will work > 100% of the time, we currently have a less than 40% success rate with inbound > faxes being the worst. > > Any insight anyone has would be greatly appreciated! > > Best Regards, > >
You could use a cisco ata 186. There aren't very cheap, but I have made them work on several of my customer sites with faxes. The ata just registers to the * server as a SIP endpoint. Also, echo cancelling and other "intelligent" things are bad when dealing with faxes and modems. Just use the cisco ATA (or any simple vegastream ATA device) to send / receive faxes. Codec should always be G.711 and no CNG or VAD or echo canceling should be used, fax machines take care of that themselves. (Contact me of list if you any of the mentioned devices) Joash joash@kahuna.nl -----Original Message----- From: asterisk-users-bounces@lists.digium.com [mailto:asterisk-users-bounces@lists.digium.com] On Behalf Of Remco Barende Sent: Thursday, January 05, 2006 4:42 PM To: Asterisk Users Mailing List - Non-Commercial Discussion Subject: Re: [Asterisk-Users] Fax with Asterisk and Sipura 2100 I tried to get it working for a very long time (over a year) with every possible set of config parameters I could find both for * as well as for the Sipura's. Echo cancelling etc. etc. all changed but still problems. I tried to get it working on an * box with a BRI line. Finally I have given up and attached a traditional ISDN -> Analog (A/B) converter to the ISDN line for the faxing bit next to Asterisk. I have yet to find a similar solution for faxing with a PRI, I'm afraid it will be impossible because as far as I know it's not possible to hook up some sort of A/B adapter next to the * box on one pri line. I think it can work if your fax machines are capable of capping fax tx/rx speeds to 9600 baud maximum without error correction. However it seems that not a single producer of FAX equipment (be it modems, all-in-one devices or even dedicated fax machines) offer such an option. HP doesn't seem very interested in capping the fax speeds for their all-in-one thingies. All fax products keep trying to transmit/receive at higher speeds after which the fax will fail completely or after the second page. Maybe there is a solution coming for PRI faxing. Junghanns informed me some time ago that they were working on a PRI card with a possibility to sync the clock to other cards. If this works in theory you could use a Junghanns PRI card and a Junghanns BRI card, sync the clocks and keep the path fully digital without lost frames. On their website however they only mention the possibility to interconnect the PRI cards, not (yet?) PRI <-> BRI. On Thu, 5 Jan 2006, Darrell Long wrote:> I know the subject of faxing has been covered in some detail, but Iwas> wondering if anyone has a hardware configuration similar to ours thathas> faxes working successfully and would be willing to share any > settings/insight. > > We are unable to fax reliably with a Sipura 2100 connected toAsterisk. We do> not route calls over the Internet and our network has very lowlatency. The> Asterisk servers connect to Cisco Routers that have PRIs from various > carriers. We have all the recommended settings in the Sipura ATA, withEcho> Cancellation and Silence Suppression off, uLaw only for the codec,etc.> > While I realize that no faxes going through passthrough like this willwork> 100% of the time, we currently have a less than 40% success rate withinbound> faxes being the worst. > > Any insight anyone has would be greatly appreciated! > > Best Regards, > >_______________________________________________ --Bandwidth and Colocation provided by Easynews.com -- Asterisk-Users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users