Steve Lingo
With nearly 20 years in telecom, Steve has managed products, partners, and product marketing activities around the globe. He joined...
Read Full Bio >>

Steve Lingo | May 02, 2013 |


Centralized SIP: How Many Enterprise Service Locations are Optimal?

Centralized SIP: How Many Enterprise Service Locations are Optimal? Even with centralized SIP, there are quite a number of flavors and factors to consider.

Even with centralized SIP, there are quite a number of flavors and factors to consider.

When considering SIP trunking solutions, your enterprise has the option to employ a separate SIP access circuit at each location (a "distributed" architecture), or you can consolidate and route all VoIP traffic, including branch site traffic, over just one or a few sites ("centralized"). Last month we looked at the advantages and disadvantage of those options. There are good reasons for each, and the option that's best for you will depend on the nature and needs of your organization. Since the majority of organizations decide to use a centralized model, let's explore that option a little closer.

With centralized SIP, all sites on your network are connected with a private network--typically MPLS-- and PSTN connectivity is provided at only one or a few locations. These centrally-connected sites are often referred to as Enterprise Service Locations (ESLs). In general, the fewer ESLs you have, the greater the savings.

Total Cost of Ownership (TCO) savings of 30-50% are widely reported when moving to centralized SIP trunks from TDM, and can be as much as 70% when all inbound/outbound PSTN traffic and Internet traffic is consolidated over one ESL. When you have only one ESL, you eliminate all the other PBXs and session border controllers, as well as all PSTN and Internet access circuits at every site but the ESL. You also gain considerable savings through the simplified management and reduced maintenance costs achieved by eliminating those extraneous elements.

Additionally, because you can run all of your enterprise PSTN and Internet traffic over one unified access circuit instead of many, you can run it far more efficiently and eliminate all the "lost" bandwidth that comes with sizing individual circuits for each service at each site. And then there's the additional benefit of the efficiency increasing as the number of users and time zones increases. Other factors aside, consolidating everything over one ESL will absolutely produce the biggest savings and fastest ROI. But it's not that simple because, like most things, there are trade-offs.

Potential Dangers
The downside, of course, is that a single isolated ESL creates a single point of failure, which is unacceptable for most. Some smaller organizations may decide that if a vendor provides 99.9% uptime, that's only 2.6 business hours a year (10 hours a day * 260 business days per year * 0.1%), and given that most employees have cell phones, the business disruption cost from an occasional outage is less than the cost of provisioning redundant ESLs. They may provision a modest PRI or BBL (broadband loop) for mission critical traffic and 911, but not a fully redundant backup solution at another location.

But even with a strong 99.9% up-time guarantee, if you're a high-volume business that has high-dollar, mission critical traffic 24x365, 99.9% uptime means you may be down nearly 9 hours a year and still be within the vendor's guarantee. And what if it goes down for longer? For most enterprises the risk is unacceptable, so they provision a second, and sometimes a third ESL. Some go the extra distance to also retain a few PRIs with another carrier for back-up. For some, business continuity is so important they provision redundant ESLs with more than one carrier and back-up PRIs.

Redundancy Options
There are a number of ways to achieve varying degrees of reliability, and the "best" solution will be different for everyone, depending on their unique cost vs. benefits appetite. The following loosely summarizes the sliding scale of redundancy options:

The Impact of Geography
Beyond budget and reliability, geography is also an important factor to consider. If you're a large US company with large offices and customer pools on both coasts, it's generally preferable to provision ESLs on each coast. In addition to the reliability protection this affords, there are call routing benefits. For example, if your business has a single ESL in New York, inbound and outbound calls originating and terminating in Los Angeles would have to trombone to NY, then back to LA, potentially creating latency problems. But if you have a second ESL in LA, calls originating and terminating in the West could stay in the West, and East Coast calls could stay in the East. A very large enterprise would likely provision a third ESL somewhere else to provide further reliability and call routing efficiency.

As you can see, even with centralized SIP, there are quite a number of flavors and factors to consider. Your service provider should be able to help guide you through the options and determine the best centralized SIP solution for your organization based on number of locations that need service and where those locations are.


Check out this recap of Enterprise Connect Orlando 2017, and register now to join us in 2018 and save $200 off or get a Free Expo Plus Pass.

Enterprise Connect Orlando 2018
March 12-15 | Orlando, FL

Connect with the Entire Enterprise Communications & Collaboration Ecosystem

Stay Up-to-Date: Hear industry visionaries in Keynotes and General Sessions delivering the latest insight on UC, mobility, collaboration and cloud

Grow Your Network: Connect with the largest gathering of enterprise IT and business leaders and influencers

Learn From Industry Leaders: Attend a full range of Conference Sessions, Free Programs and Special Events

Evaluate All Your Options: Engage with 190+ of the leading equipment, software and service providers

Have Fun! Mingle with sponsors, exhibitors, attendees, guest speakers and industry players during evening receptions

Register now with code NOJITTEREB to save $200 Off Advance Rates or get a FREE Expo Pass!

March 7, 2018

Video collaboration is experiencing significant change and innovation-how can your enterprise take advantage? In this webinar, leading industry analyst Ira Weinstein will present detailed analysis

February 21, 2018

Business agility has become the strongest driver for enterprises to begin migrating their communications to the cloud-and its a benefit that enterprises are already realizing. To gain this benefit

February 7, 2018

Enterprises are starting to grasp the critical importance of security and compliance in their team collaboration deployments. And once the risks are mitigated, your enterprise can integrate these n

February 16, 2018
What trends and technologies should you be up on for your contact center? Sheila McGee-Smith, Contact Center & Customer Experience track chair for Enterprise Connect 2018, gives us the lowdown.
February 9, 2018
Melanie Turek, VP of connected work research at Frost & Sullivan, walks us through key components -- and sticking points -- of customer-oriented digital transformation projects.
February 2, 2018
UC consultant Marty Parker has crunched lots of numbers evaluating UC options; tune in for what he's learned and tips for your own analysis.
January 26, 2018
Don't miss out on the fun! Organizer Alan Quayle shares details of his pre-Enterprise Connect hackathon, TADHack-mini '18, showcasing programmable communications.
December 20, 2017
Kevin Kieller, partner with enableUC, provides advice on how to move forward with your Skype for Business and Teams deployments.
December 20, 2017
Zeus Kerravala, principal analyst with ZK Research, shares his perspective on artificial intelligence and the future of team collaboration.
December 20, 2017
Delanda Coleman, Microsoft senior marketing manager, explains the Teams vision and shares use case examples.
November 30, 2017
With a ruling on the FCC's proposed order to dismantle the Open Internet Order expected this month, communications technology attorney Martha Buyer walks us through what's at stake.
October 23, 2017
Wondering which Office 365 collaboration tool to use when? Get quick pointers from CBT Nuggets instructor Simona Millham.
September 22, 2017
In this podcast, we explore the future of work with Robert Brown, AVP of the Cognizant Center for the Future of Work, who helps us answer the question, "What do we do when machines do everything?"
September 8, 2017
Greg Collins, a technology analyst and strategist with Exact Ventures, delivers a status report on 5G implementation plans and tells enterprises why they shouldn't wait to move ahead on potential use ....
August 25, 2017
Find out what business considerations are driving the SIP trunking market today, and learn a bit about how satisfied enterprises are with their providers. We talk with John Malone, president of The Ea....
August 16, 2017
World Vision U.S. is finding lots of goodness in RingCentral's cloud communications service, but as Randy Boyd, infrastructure architect at the global humanitarian nonprofit, tells us, he and his team....
August 11, 2017
Alicia Gee, director of unified communications at Sutter Physician Services, oversees the technical team supporting a 1,000-agent contact center running on Genesys PureConnect. She catches us up on th....
August 4, 2017
Andrew Prokop, communications evangelist with Arrow Systems Integration, has lately been working on integrating enterprise communications into Internet of Things ecosystems. He shares examples and off....
July 27, 2017
Industry watcher Elka Popova, a Frost & Sullivan program director, shares her perspective on this acquisition, discussing Mitel's market positioning, why the move makes sense, and more.
July 14, 2017
Lantre Barr, founder and CEO of Blacc Spot Media, urges any enterprise that's been on the fence about integrating real-time communications into business workflows to jump off and get started. Tune and....
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.