10 things you need to know about VoIP

Anybody working on a VoIP project should stand on the shoulders of those who have gone before to avoid their mistakes and glean tips that can make their own deployments go more smoothly.

In the interest of promoting this knowledge sharing, here is a list of 10 tips you should follow if you want to roll out VoIP with as little pain as possible.

1. Buy time.

Even with the smoothest deployments, things don’t always happen as planned, so build a buffer into your timeline, says Lauren Johansson, IP telephony manager for MedQuist, a medical records firm in Mt. Laurel, N.J. For example, in Johansson’s case, getting an OC-3 from her carrier took an extra six months during which MedQuist had to make do with a DS-3, a lot less bandwidth than it wanted.

2. Get everybody onboard.

Make sure business-unit leaders are on the VoIP project team so they know the details and can communicate them to their employees, giving all users a stake in the project. “This reduced switchover time and made for little need for user training,” says Randy Hillman, customer care manager for Sovran Self Storage, headquartered in Buffalo, N.Y., who oversaw a Shoretel VoIP deployment.

3. Know what you’ve got.

Along with traffic, businesses need to figure out exactly what hardware makes up the network infrastructure and more important, whether it will support technology that can improve voice quality. For instance routers and switches that support virtual LANs and traffic shaping go a long way toward carving out enough reliable bandwidth to prevent degradation of VoIP connections. “If you don’t have an accurate network diagram, you can’t do a project like this,” Johansson says.

Also, make sure all desktop deployments pass the PAS test. That is, desktop phones should have two things — power and switching (PAS). Make sure phones can be powered via standard Power over Ethernet (PoE, 802.3af is the IEEE standard). Also ensure that the IP phones being deployed have built-in LAN switch ports. This will allow for a single LAN cable to support a desktop PC and IP phone (the PC connects to a LAN port in the switch, which uplinks to the LAN). And if users require Gigabit Ethernet, make sure the IP phone has a 1000Mbps port.

4. Bandwidth control.

If audits reveal that bandwidth may be an issue, it could be time to consider an upgrade from, say, Fast Ethernet to gigabit Ethernet. Even if such an upgrade seems like overkill now, it makes sense to project network traffic increases from all applications over the next three years to determine if such an upgrade is inevitable.

LAN bandwidth turned out to be sufficient when Sovran Self Storage decided to install Shoretel VoIP gear to 330 sites, but the ATM WAN needed a bandwidth boost, says Randy Hillman, the firm’s customer care manager who oversaw the VoIP project. That turned out to be a combination DSL and cable modem network backhauled over an MPLS service and coordinated by Verizon, he says. “That lets us give priority to voice,” he says.

5. Use the right codec.

To minimize bandwidth that VoIP requires, customers can choose from a variety of codecs that take the voice stream and encode it for transmission over network wires. This can be as little as 8Kbps or as much as 64Kbps, but businesses should listen to a variety of them to determine which ones produce acceptable quality. The ones that are acceptable and use the least bandwidth are the ones to use, especially if bandwidth is tight.

Hillman says he considered going for a low-bandwidth codec, but with just a few phone extensions at each site, bandwidth isn’t an issue. If it becomes one, he plans to listen to a variety of them to pick one that delivers good enough quality.

6. Emergency! Remember 911!

VoIP doesn’t allow for easy 911 calling because the voice server has no idea where the phone is, just its IP address. The phone could be anywhere on any network segment, and its location could change if the user moves the phone to a different network jack. Emergency personnel could be sent to the wrong place. “I highly suggest that you tie phones up to an analog phone line if you can,” Johansson says. The company has 1,000 teleworkers as far away as California supported by Mitel gear. “I don’t want them calling 911 in New Jersey,” she says. “For us that was a big potential liability.”

7. Make training simple.

Mass deployments means large numbers of users that must be trained to use the new phones. In the case of telecommuters, they may be expected to install the gear as well, and that can come as quite a shock to people used to working in an office where the phones and computers are already set up. “We even used pictures with instructions: here’s your network connector. Here’s the back of your phone. Plug them into each other,” Johansson says. “We couldn’t have done this project without good documentation.” A list of FAQs kept help-desk calls to a minimum, she says.

Also, deploy IP phones in public areas — such as conference rooms, lunch rooms — before a formal IP phone training program, and well before plunking dozens or hundreds of handsets down on users desktops. IT and telecom experts say this will give users a glimpse at the new technology, and allow curious employees to try out the hardware. This is a lower-risk approach to having people use unfamiliar IP phone technology for their daily jobs right away.

8. Gateways to savings.

Instead of blanketing a corporate site with IP phones — which can cost $200 to $900 — consider deploying low-cost analog handsets with analog-to-IP gateways, for connecting the traffic to the VoIP network. Odds are you will need analog gateways anyway, to support fax machines, which don’t behave well on IP links. If simple analog phones can do the job in certain areas — such as hallways or loading docks — it could be a money-saver. This is a common practice in colleges with hundreds of phones in dorm rooms and hospitals with dozens of hallway and exam-room phones.

“But only a few of our buildings have switches that are totally redundant,” says Elwyn Hull, director of telecommunications at University of Texas Southwestern Medical Center at Dallas, which runs a hybrid IP and analog/digital voice network from Siemens. While IP phones sit in administrative offices, remote clinics, and satellite sites, the emergency rooms, operating rooms and critical-care areas have analog phones. “In critical areas that deliver a lot on patient care, we don’t feel secure enough to go with a VoIP solution,” Hull says.

9. The soft touch.

Consider softphones as an alternative to desktop phones for certain types of employees. Tech-savvy users or those who regularly work from different locations — such as branch offices, home offices, or on-site with customers — are good candidates.

“You can just go anywhere with the softphone, and have your desk extension right there,” says Kurt Paige, network administrator for the American National Bank of Texas, who estimates that 25% to 30% of the bank’s workers will have Cisco softphone clients installed on their notebooks over the next several years. “This will allow workers to have the option to work either in the office or at home.”

It’s also a less-expensive proposition for supporting remote workers. Cisco IP softphone license costs around $100, or less when bought in larger quantities. IP handsets with similar features as the softphones typically cost $300 to $400.

10. Remote control.

Find out how remote management applies to your IP PBX: can you run on your IP PBX or call server the same tools you use to remotely manage, reboot and configure your regular mail/file/print servers? IP PBXs can run on platforms varying from Windows, to embedded Linux and Unix, and each server type supports different remote-access/control applications. Cisco, for instance, recommends Virtual Network Computing (VNC) as its remote-access/control tool for the CallManager IP PBX. But one Cisco VoIP user at a Midwestern company — who spoke to Network World anonymously — said VNC on CallManager was an issue, as it was against the company’s policy to run VNC over the corporate network.