Eric Krapf
Eric Krapf is General Manager and Program Co-Chair for Enterprise Connect, the leading conference/exhibition and online events brand in the...
Read Full Bio >>

Eric Krapf | July 17, 2013 |


More SIP Trunking Gotchas

More SIP Trunking Gotchas Number porting, Caller ID, E911, "bursting," and other issues can complicate and slow down your migration.

Number porting, Caller ID, E911, "bursting," and other issues can complicate and slow down your migration.

Man, this SIP Trunking issue just keeps rolling along. Last week, we held a "virtual event" on SIP Trunking--6 webinars back to back, plus vendor spaces where attendees could gather information from the virtual event's sponsors--Genband, XO Communications, Cisco, Oracle, Sonus, and Level 3. Pre-registration was among the highest we've had for this kind of event, and attendance likewise was substantial--almost 400 people listened to our keynote webinar from Jim Allen and Dave Stein, the independent consultants who serve as our SIP Trunking gurus.

As we've seen in the past, the topics that drew the most attention from speakers and questions from the audience centered around the real nuts-and-bolts issues, the "gotchas" that can trip up a SIP Trunking implementation. Some of the challenges that XO highlighted in one webcast included:

* Porting: To ensure that numbers are ported to the new access trunks without disruptions, enterprises need to make sure they have an accurate inventory of current DIDs, and that if they're switching carriers, they're prepared to deal with, shall we say, less than enthusiastic cooperation from the carrier losing the business. The bottom line: Start addressing this issue early in the process and understand the likely pitfalls.

* Caller ID: Because SIP Trunking allows multiple locations to sit behind a single, centralized SIP Trunk, you may encounter problems passing accurate Caller ID information through to the called party. Our XO panelists pointed out that, in the PSTN world, the physical location of the caller--the originating LATA--is always known, and this information can always be used by the carrier to deliver accurate Caller ID. In contrast, the SIP Trunking carrier may not know the physical location of the caller, so the system must be configured to make sure it can pass the Caller ID for the DID in a way that can be read at the remote end. (A variation on this is the challenge of E911 and making sure that a call reaches the Public Service Answering Point or PSAP that serves the physical location of the caller.)

* Fax, modems, and alarms: These legacy systems will remain in place, so enterprises have to plan carefully to make sure they can make the transition. Fax is an ongoing issue that more people are talking about, but our XO speakers noted that if analog modems can't be phased out, you may need to retain POTS lines to serve them--i.e., there is no solution within SIP Trunking at this time.

* "Bursting": By now, many carriers offer a service in which enterprises can flexibly use the capacity they're buying--in other words, instead of being restricted to a given amount of bandwidth at each location, with the risk of overprovisioning at some places or times and underprovisioning at others; the carrier may offer a "pool" that lets you reassign capacity dynamically so that you optimize your bandwidth utilization. But, as Steve Lingo of XO has warned in the past, these "bursting" offers vary among carriers, so you have to understand what you're buying.

We keep waiting for SIP Trunking to become commoditized and simple to adopt and implement--at which point, it will presumably no longer be a hot topic. That keeps not happening, because there seems to be an endless layer of challenges and problems that need to be solved before you can implement SIP Trunks and capture the savings they promise, while not having them alter your telephony environment in ways that hurts the business.

The bottom line is that a SIP Trunking-for-PRI swapout is not as straightforward as an MPLS-for-frame-relay swapout. Getting the benefits without losing the features is a much more detailed, tricky process. As long as that remains the case, SIP Trunking will be a big draw.

By the way, if you missed the virtual event, you can view all the webcasts and see the sponsor materials on demand.

Follow Eric Krapf and No Jitter on Twitter and Google+!
Eric Krapf on Google+


July 12, 2017

Enterprises have been migrating Unified Communications & Collaboration applications to datacenters - private clouds - for the past few years. With this move comes the opportunity to leverage da

May 31, 2017

In the days of old, people in suits used to meet at a boardroom table to update each other on their work. Including a remote colleague meant setting a conference phone on the table for in-person pa

April 19, 2017

Now more than ever, enterprise contact centers have a unique opportunity to lead the way towards complete, digital transformation. Moving your contact center to the cloud is a starting point, quick

June 28, 2017
Communications expert Tsahi Levent-Levi, author of the popular blog, keeps a running tally and comprehensive overview of communications platform-as-a-service offerings in his "Choosing a W....
June 9, 2017
If you think telecom expense management applies to nothing more than business phone lines, think again. Hyoun Park, founder and principal investigator with technology advisory Amalgam Insights, tells ....
June 2, 2017
Enterprises strategizing on mobility today, including for internal collaboration, don't have the luxury of learning as they go. Tony Rizzo, enterprise mobility specialist with Blue Hill Research, expl....
May 24, 2017
Mark Winther, head of IDC's global telecom consulting practice, gives us his take on how CPaaS providers evolve beyond the basic building blocks and address maturing enterprise needs.
May 18, 2017
Diane Myers, senior research director at IHS Markit, walks us through her 2017 UC-as-a-service report... and shares what might be to come in 2018.
April 28, 2017
Change isn't easy, but it is necessary. Tune in for advice and perspective from Zeus Kerravala, co-author of a "Digital Transformation for Dummies" special edition.
April 20, 2017
Robin Gareiss, president of Nemertes Research, shares insight gleaned from the firm's 12th annual UCC Total Cost of Operations study.
March 23, 2017
Tim Banting, of Current Analysis, gives us a peek into what the next three years will bring in advance of his Enterprise Connect session exploring the question: Will there be a new model for enterpris....
March 15, 2017
Andrew Prokop, communications evangelist with Arrow Systems Integration, discusses the evolving role of the all-important session border controller.
March 9, 2017
Organizer Alan Quayle gives us the lowdown on programmable communications and all you need to know about participating in this pre-Enterprise Connect hackathon.
March 3, 2017
From protecting against new vulnerabilities to keeping security assessments up to date, security consultant Mark Collier shares tips on how best to protect your UC systems.
February 24, 2017
UC analyst Blair Pleasant sorts through the myriad cloud architectural models underlying UCaaS and CCaaS offerings, and explains why knowing the differences matter.
February 17, 2017
From the most basics of basics to the hidden gotchas, UC consultant Melissa Swartz helps demystify the complex world of SIP trunking.
February 7, 2017
UC&C consultant Kevin Kieller, a partner at enableUC, shares pointers for making the right architectural choices for your Skype for Business deployment.
February 1, 2017
Elka Popova, a Frost & Sullivan program director, shares a status report on the UCaaS market today and offers her perspective on what large enterprises need before committing to UC in the cloud.
January 26, 2017
Andrew Davis, co-founder of Wainhouse Research and chair of the Video track at Enterprise Connect 2017, sorts through the myriad cloud video service options and shares how to tell if your choice is en....
January 23, 2017
Sheila McGee-Smith, Contact Center/Customer Experience track chair for Enterprise Connect 2017, tells us what we need to know about the role cloud software is playing in contact centers today.