Several of these RBS T1s have been here for many years and before we moved to Asterisk a few pieces of phone hardware we used were not PRI-compatible. There is also the fact that we still use Channel banks which are also RBS. We have started a long process of switching to PRIs as our RBS T1 contracts expire, but that is going to take another 2 years. Pricing was not really an issue.
MATT--- -----Original Message----- From: Tom [mailto:[EMAIL PROTECTED] Sent: Thursday, April 07, 2005 11:29 AM To: Asterisk Users Mailing List - Non-Commercial Discussion Subject: Re: [Asterisk-Users] My Sangoma Experience - Review Thanks for the informative review Matt. Please tell why you are using RBS T1 trunks instead of PRIs. Is it the cost or availability issue from the ILEC/CLEC or is there some other advantage. PRIs and RBS T1s are about the same price in my part of the world. Tom At 09:20 AM 4/7/2005, you wrote: >My Sangoma Experience in Asterisk: 2005-04-07 > >Having pushed my Digium Asterisk systems to their capacity many times and >figuring out the limits of the Digium hardware I decided it was time to test >an Asterisk-compatible Sangoma Quad T1/E1 card(AFT-A104u) to see if they >live up to their hype of being more efficient than the Digium >variety(T405P). I had talked with someone from Sangoma before at Astricon, >but it was rather informal, he didn't have any literature and I was rather >swamped at the time as it was. Then I saw a posting on the asterisk-users >list about the claims that the Sangoma card does echo-cancelation better as >well as using far less interrupts than Digium hardware(a big bottleneck with >busy Digium systems). > >I emailed Sangoma(they are located in Canada) for a quote and quickly >received a phone call from them. They were very interested in getting my >feedback on using their quad port T1/E1 card with Asterisk and they quoted >me a discounted price of $1190 US for the card(They said retail was $1700 US >[Digium quad-cards are $1495 retail but you can get them through resellers >for a couple hundred less]). The Sangoma card comes with a 30-day money back >guarantee and a 3 year warranty. > >When I received the card I noticed a couple things right away, it was a very >professionally packaged item and it came with 4 T1 cables in the box as well >as documentation and all of the other pretty things you expect in a retail >package. The second thing I noticed is that the card was compatible with a >2U form-factor(That's right, they crammed 4 T1/E1 ports together so it can >fit in a 2U case vertically) This was achieved in-part because the ports are >actually on a fixed daughter card, but it did bring up the thought that they >could actually cram 6 ports on one of these cards :) > >Next I started to sort through the documentation and files on their FTP >site. I noticed something I wish Digium cards had: User-upgradable firmware >on the board(I have previously had to return an early version of the T410P >Digium board to get a newer one with newer firmware on it). > >Let the installation begin. I started by downloading and installing Asterisk >as usual(zaptel, libpri, asterisk[version 1.0.6]), then I downloaded and >installed Wanpipe release 2.3.2 beta6. I could now see my card and went into >the wancfg utility to configure my card. Here's when it stopped being a >smooth experience. I tried installing it by the asterisk instructions found >on the FTP site(which I found out later were out of date and incorrect) and >eventually it all worked up until the final starting step. The drivers saw >the card, but said nothing was connected to them which I thought was a >strange problem since you don't have to have anything connected to a Digium >card for Asterisk to fully startup. So I emailed tech support and walked >through some reconfiguration steps and then after a few more emails back and >forth it came out that they had a problem with D4/AMI signalling on a RBS >T1(which they say they will have a fix for at some undefined time in the >future). After switching the wanpipe config for the first span to B8ZS/ESF >with a PRI T1 I was able to run ztcfg and asterisk. I placed some test calls >and all went well, at least until I tried hooking up a live RBS(Robbed-bit, >24 full channels not PRI) E&M Wink T1. It turns out that the guys at Sangoma >have never had a customer that used E&M Wink start and accordingly they have >never tested their cards with it, and of course it didn't work. So another >email and call to Sangoma and they started working on a fix. Two days later >they added a Wink for wink start T1s and sent me a new version of the >software. I loaded it and it worked, but all audio and call detects stopped >working if I tried to use more than 10 of the RBS T1 channels, so back to >Sangoma for another new driver version. After a few days, and a few more >driver versions, they came up with one that seemed to fix all of the >problems I was having before so I did my simple stress test of picking up, >hanging up and redirecting to meetme of about 52 Zap lines and all went >well. Now on to the performance testing. > >For a performance test, I swapped out an identically configured machine that >had a Digium T405P with my test machine and put it live in company >inbound/outbound call center during off-hours to test(This server usually >handles over 20,000 calls in/out a day with lots of recording going on >across T1s, SIP phones and some IAX2 trunks). This server has two RBS T1s, >one PRI T1 and one Channel Bank. I placed a test call out of the channel >bank through the PRI and then started automated calls from the two RBS T1s >to go into meetme conferences. The performance test ran great and it did >prove that there is reduced CPU usage on a Sangoma board as compared to a >Digium board. For a running time of about an hour the CPU usage was between >30% and 50% lower with the Sangoma board on the identically configured >machine. This was just doing some random calling maintaining 48 >conversations across all 4 T1s with calls lasting no longer than 1 minute. >With these results I was very encouraged and decided to put the card into >production. > >The production machine that I was replacing is one of our higher-volume >Asterisk servers that routinely handles over 40,000 calls a day. To test >compatibility and reliability of all of the hardware aside from the Sangoma >card, I ran the server in production with a Digium card with no problems >then the next day I put the Sangoma card back in and started it up. About 5 >minutes into production everything was going great, the load was very low >for this machine and I was not noticing any channel_walk_lock warnings like >I periodically see on Digium systems. Then at 10 minutes something happened >and the card was not detecting Answers on any calls coming in or going out >on either the PRIs or the RBS T1s. I had to reboot the machine to get it to >start detecting Answers again. This was not good. I thought it was a random >problem so we just started back up again, and then again after about 10 >minutes it happened again. I then put the Digium card back in quickly and >rebooted and the server finished out the shift with no problems. The next >day I took the server out of production and started running some more stress >test on it. I couldn't get it to duplicate what had happened the day before >even at higher volumes of calls than it was handling in the live >envorionment. The next week we tried it again in production and the same >thing happened except this time the machine froze. I was pretty sure that >this was an issue with RBS T1s so I put the machine to the task of doing >some PRI call routing between several Asterisk servers and it works just >fine now PRI-only with no problems. > >Overall it isn't as easy to install a Sangoma Quad-T1/E1 card on an Asterisk >system as it is to install a Digium card. But the support is very responsive >to installation problems and I'm sure as more Asterisk users try Sangoma >cards, the instructions will be updated more frequently and go more in-depth >into the options offered by Sangoma cards. Throughout my tests I installed >the Sangoma card and drivers several times on a few servers and by the end >it was taking me about 10 minutes extra per install to get the Sangoma cards >and their drivers ready for Asterisk usage. > >One minor confusing moment was realizing that Port 1 is on the bottom of the >card unlike Digium where it is on the top. A minor annoyance with the >Sangoma quad T1/E1 card is that you need to create a wanpipe config file for >each span on the card and use another utility to specify the order in which >they are loaded. One more item of note is that you need to wait several >seconds after running 'wanrouter start' before you can start ztcfg or >asterisk, if you do not, the spans may not come up properly. > >I am conflicted partially because when you buy a Digium card from Digium you >are directly supporting the company that is the primary contributor to and >maintainer of Asterisk(not to mention the lead-developer and creator of >Asterisk is the CEO) and it is very important to support the core of this >great application. It is important to note however that Sangoma has been >contributing code to GPL Asterisk for a while now(they just recently started >contributing directly as Sangoma) and seems to be doing more development >with Asterisk as they get more Asterisk users as their customers. I do hope >that Digium takes a look at what Sangoma was able to accomplish for roughly >the same price point in a smaller form factor and will hopefully make some >of the same advances in their cards in the future. > >I would not recommend a Sangoma card for a beginner user or those who depend >on RBS T1s. Intermediate users and Asterisk Gurus who only use PRI T1s might >want to try one of these cards if only to see if they can squeeze a few more >channels of capacity out of their systems or get better echo cancellation >and control of their card. There is no question that Sangoma has done a lot >to improve on the zapata core hardware design and they will hopefully drive >innovation in this growing market, competition is a good thing. > >Installation and test were done on Intel P4 systems running Slackware Linux >10.1 with a custom 2.4.29 SMP kernel. > >MATT--- _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users