Virtualization a challenge for IP contact centers

The needs of real-time applications must be respected

High availability -- redundancy that is critical to contact center reliability -- is another challenge in virtual environments, Wolf says. "Your typical high-availability solution today is only able to detect failure of the physical server and relocate the virtual machine as a result of that," he says. "In general it has very little insight into what is happening inside the virtual machine."

The virtual machine as black box

The virtual machine is treated as a black box, he says, which means an application can hang up inside a virtual machine without the high-availability software knowing about it. "That virtual machine would continue to operate as if nothing is going wrong," he says.

Similarly, if server hardware fails, the virtual environment needs to respond quickly to maintain calls, Wolf says. "What I mean by that is if there is a partial failure on the physical host I don't want complete loss. I might have, say, a network card go down, which in a contact center can be critical in terms of the amount of I/O I'm going to lose," he says.

In that case it would be desirable to live migrate the virtual machines on the affected host to a healthy machine. One solution called continuous availability keeps a hot standby virtual machine ready in the same state as the active virtual machine.

"With that I'm able to run a single VM on multiple physical nodes simultaneously and keep that virtual machine in lockstep so if I do have a physical node failure, the VM continues to run, and I do not lose any application state as a result," he says. Marathon Technologies has such a product, he says. "That's the type of intelligence that still needs to evolve," he says.

Beyond server virtualization, virtualizing the desktops of contact-center agents can produce further benefits but requires care to avoid degraded voice quality, says Robert Iglehart, senior vice president of IS at Thomas L. Cardella (TLC) & Associates, a contact-center provider in Cedar Rapids, Iowa. The firm uses Citrix desktops for the business applications used by agents, but relies on Avaya hard phones for voice.

"There's enough other things to worry about than to worry about what's the person hearing from me at the other end," he says. "Am I cutting out? Is there a big delay? Are we having a walkie-talkie effect? We just really don't have any tolerance for that, and that's what's keeping us from virtualizing the voice."

For contact-center applications that are not demanding of CPU, virtual machines are ideal, Iglehart says, for all the same reasons virtual machines are used in general -- redundancy and moving virtual machines on the fly as capacity demands.

"It's more reliable because you're concentrating your applications in the data center on better equipment. Storage is put on a SAN. "You don't have desktops on agent stations getting beaten around every day," he says.

Join the PC World newsletter!

Error: Please check your email address.

Tags IP contact centresvirtualisation

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Tim Greene

Show Comments

Cool Tech

Crucial Ballistix Elite 32GB Kit (4 x 8GB) DDR4-3000 UDIMM

Learn more >

Gadgets & Things

Lexar® Professional 1000x microSDHC™/microSDXC™ UHS-II cards

Learn more >

Family Friendly

Lexar® JumpDrive® S57 USB 3.0 flash drive 

Learn more >

Stocking Stuffer

Plox Star Wars Death Star Levitating Bluetooth Speaker

Learn more >

Christmas Gift Guide

Click for more ›

Most Popular Reviews

Latest News Articles


GGG Evaluation Team

Kathy Cassidy


First impression on unpacking the Q702 test unit was the solid feel and clean, minimalist styling.

Anthony Grifoni


For work use, Microsoft Word and Excel programs pre-installed on the device are adequate for preparing short documents.

Steph Mundell


The Fujitsu LifeBook UH574 allowed for great mobility without being obnoxiously heavy or clunky. Its twelve hours of battery life did not disappoint.

Andrew Mitsi


The screen was particularly good. It is bright and visible from most angles, however heat is an issue, particularly around the Windows button on the front, and on the back where the battery housing is located.

Simon Harriott


My first impression after unboxing the Q702 is that it is a nice looking unit. Styling is somewhat minimalist but very effective. The tablet part, once detached, has a nice weight, and no buttons or switches are located in awkward or intrusive positions.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?