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SIP Trunking Rocks (or does it. . . .hmmm)

July 16, 2009 - 7 Comments

We had a highly attended, very interactive TechWiseTV webcast this week! Over 1000 of you all joined us live to hear about SIP Trunking and we received over 300 questions during the webcast — thank you for attending!For those who didn’t attend, you can still catch the recording of the SIP Trunking webcast.So what did we learn? We learned that SIP trunking is a pretty cool new frontier. But, like all frontiers (no Star Trek comments, please) it is a bit wild. Darryl Sladden (aka SIP Guru) netted out a few key components to think about when deploying SIP trunks from a carrier. Three things that really stood out for me were:• If your connection provider (T1, DSL, whatever) is not your SIP provider, you are going to be hard-pressed to guarantee QoS.• Faxing can be done, but you should consider a Plan B when it comes to fax and modem connections. I’m also gonna go out on a limb here and suggest finding IP based solutions to replace those old analog fax and modem solutions.• What we consider basic features today in the IP world, such as putting a call on hold, get way more complex in a SIP world where there are multiple ways of implementing this feature. Where does that leave us? Do we boldly go where no one has gone before (ok, I did it to myself with the Star Trek reference). I believe the answer is yes — but with caution, with lots of testing, with a good Plan B in mind and a sense of what REAL value is being provided to your company by your SIP carrier. HUGE Thanks goes to Jimmy Ray Purser for the demo (and hacks), to Darryl Sladden for the great insight on the real SIP world, and to Christina Hattingh for answering literally hundreds of questions on the webcast. For the slides from the show and on-going Q&A discussion, visit us on the Collaboration Community.

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  2. Their Edgemark and QoS is a half truth. The only way it would help your issues is if you ran both your voice and data through it. Unless the carriers support QoS end to end, it’s all half baked.To eliviate some of your issues with large downloads, you can bandaid the problem by limiting your incoming bandwidth for data, so that some is left over for voice.

  3. Well I never heard from anyone Sam. We don’t have the EdgeMarc device, I was hoping to avoid the extra $53 a month I was told it would cost after I queried our poor QoS situation. But if that’s only way, then I guess it’s what we’ll have to do. We cannot carry on like this – users are getting really mad. Too bad my vendor never explained these pitfalls to me up-front.

  4. Ed,Thanks for letting us know you’re having difficulties. As I understand it, a big portion of our QoS relies on the EdgeMarc device that we ship to the majority of our customers – did we set one up for your solution? Either way, I’ve got the ball rolling over here to address your problem – expect to hear from us soon.Best regards!

  5. I’m finding SIP awesome, but the point about QoS difficulties is well taken. We have Qwest as our MPLS provider and as our SIP provider and QoS is terrible when our voice connections come under pressure from data downloads. Surely could mark their SIP data to enable us to to get QoS? I’m not sure if they’re unable or just unwilling.

  6. SIP Trunking DOES rock! Pardon me while I pour you some of my delicious Kool-Aid:While the main three objections to SIP Trunking as a TDM replacement are perfectly valid, business savvy ITSPs such as my firm,, are quite aware of these issues and address each one carefully to mitigate the risks while maintaining the benefits. For instance, we are a full service provider – our BoxSet bundles include everything from Internet & SIP Trunks to an edge QoS device, neatly countering the multiple provider argument.The one point we could not address until this year was the savings. Yes, large enterprises enjoyed lower TDM prices due to bulk (SMB was never so lucky, which is why SIP is such huge savings for them). However, now that we built our nationwide network and have owner economics, we can once again beat TDM soundly on price.