10 Best Practices for Managing a Converged Network

Updated: August 20, 2012

Issue

 

The power of a converged network — a single IP network that simultaneously handles data, voice, video and perhaps even optical traffic — is indisputable. Convergence of communications technologies is letting businesses respond to opportunities in the marketplace in real time and with greater flexibility. Because a converged network combines systems on a single infrastructure — such as telephony layered on the IP network — it reduces a variety of costs. For example, IBM reports that advanced audio conferencing in a converged network can save as much as 35 percent over the cost of traditional approaches.

Transforming your enterprise into a seamlessly converged network won't happen overnight, but your business will quickly reap the benefits from myriad applications based on a converged network, including multimedia email, instant messaging, Web and videoconferencing, and unified collaboration. A converged network also enables policy-based routing of phone calls to wired, IP and mobile phones around an enterprise, as well as Web portal-based management of personal call features and policies. Ultimately, these solutions aim to make users more productive and more responsive to your customers' needs.

According to most IT industry analysts, running converged applications like VoIP is no longer a question of "if" but of "when." If that "when" is now for your organization, following these 10 best practices for configuring, managing and maintaining a converged network will help you stay on budget — and avoid one of those notorious VoIP flameouts.

 

Strategies

1. Clearly define — and refine — your organization's goals. A converged network and its applications, particularly VoIP, will simplify the enterprise infrastructure. More importantly, it can improve customer service, almost eliminate long-distance phone charges and help the organization become more efficient — but only if the organization's business goals are clearly identified and understood by the IT staff. It's important to regularly check in with the business people to make sure the design of the converged network continues to meet their requirements.

2. Test the network with assessment tools. Before you start rolling out a converged application like VoIP, you need to know that the network can support it. You also need to be sure that no applications are running behind the scenes that may interfere with the voice traffic.

"When an organization moves to a converged network, at that stage, we see the network as the foundation for so many critical business functions. It's important for an IT manager to know what's really running on a network," said Jayanth Angl, a research analyst with Info-Tech Research Group in London, Ontario, Canada.

Start with an end-to-end baseline assessment of the entire network that will handle voice and data traffic, LAN and WAN, including existing bandwidth, latency, jitter and utilization. Review the network's switch and router environment, including availability of QoS (Quality of Service) features, the existing and planned network topology and additional network-segmentation requirements. Also, perform load testing to see if the current infrastructure can handle the expected amounts of data and voice traffic at the same time.

Once these time-sensitive applications are deployed, you should continue testing and monitoring their performance and utilization so you can quickly diagnose and resolve problems, as well as easily expand the converged network. Angl recommended using either a stand-alone protocol analyzer to get an overview of the traffic currently traveling the network or, for a more comprehensive view, a traffic-flow-analysis tool. With traffic-flow analysis, you get insight into the factors that impact VoIP performance, including packet latency, loss and delay. Real-time, end-to-end monitoring and performance testing is the only way to preserve the level of voice quality users except from their phone calls.

3. Establish, configure and manage QoS metrics. "QoS needs to be properly designed from the beginning," explained Vanessa Alvarez, who called QoS the most important aspect of a converged network. Alvarez is an associate analyst who specializes in enterprise and systems network management for Yankee Group Research Inc. in Boston. "QoS metrics are the primary building blocks of your overall quality of service strategy," she said.

Data traffic can withstand some packet loss or packets delivered out of sequence, but voice traffic cannot — the call would be choppy at best, confusing at worst and certainly frustrating for users. The delay between one speaker and the other should not last more than 250 milliseconds, or conversation becomes too difficult, according to Avaya Inc., a telecommunications systems vendor headquartered in Basking Ridge, N.J.

Your QoS strategy should extend from the LAN through the WAN, which means that you may have to upgrade any legacy routers and switches to devices with QoS functionality. Use QoS to prioritize traffic on the network. Priority one is voice traffic, with guaranteed latency and bandwidth; priority two is data traffic considered important, with a guaranteed bandwidth level; priority three is the rest of data traffic, which gets processed on a best-effort basis.

4. Ensure security for the converged network. One of the lingering doubts about VoIP has been a company's ability to appropriately secure the voice traffic — and how slow security measures may make that traffic. It's important to balance an acceptable delay in communications traffic with necessary security, as well as to determine what level of risk is acceptable to your organization. For instance, financial institutions may have to encrypt voice traffic to maintain privacy, even if that means taking a hit in the quality of voice traffic.

When rolling out converged applications, put up defenses specific to the attacks that are associated with VoIP — including DoS (denial of service), spoofing, eavesdropping and man-in-the-middle attacks — and privilege escalation. Therefore, you should regularly revisit your organization's security policies related to these vulnerabilities.

5. Ensure reliability and resiliency for the converged network. A key component of a converged network is VoIP, which adds software to the enterprise, as well as a range of new hardware in the form of IP phones, voice communications servers and media gateways. Your disaster-recovery plan must be expanded to include these new applications and devices, so that all types of traffic will continue to function or can be quickly restored in the case of failure.

6. Plan for expected — and unexpected — voice capacity. Just as you've already estimated the amount of bandwidth your network needed to handle all the data it serves, you should estimate the amount of bandwidth that the converged network needs to support toll-quality calls. NEC Unified Solutions Inc., a communications solutions vendor in Irving, Texas, offers an equation for estimating voice bandwidth: The number of calls multiplied by the amount of bandwidth per call equals the amount of bandwidth required. (The bandwidth per call is a factor of the codec you use to connect voice calls between VoIP endpoints and the packetization interval in milliseconds.)

According to NEC, you can usually calculate your total voice bandwidth and multiply that by three to land at the bandwidth that your converged network requires for all data. This works as long as the bandwidth you require for data is less than twice the bandwidth necessary for voice traffic.

7. Always choose standards-based solutions. Enterprise networks tend to grow organically, gaining new hardware and applications as a company adds employees or new business process. Very few networks can claim to originate from just one vendor, and interoperability is paramount.

"Ensure your vendors are following the standards established by most of the standards bodies out there. It ensures interoperability — with mergers, acquisitions, and takeovers, the enterprise network becomes a mashup of different vendors," said Alvarez.

Protocols and standards associated with VoIP include SIP (Session Initiation Protocol), RVP over IP (Remote Voice Protocol Over IP Specification) and H.323.

8. Train IT staff and users across your organization. Although it may seem a simple switch for employees to just use a new IP phone like they used their old desk phone, a VoIP system offers advanced capabilities that users won't automatically know how to use. Proper training ensures that users will make the most of the new system and that the investment won't be wasted. When budgeting for a unified communications deployment, include training costs for users as well as IT staff.

9. Don't play the blame game. Things will go wrong. But if the separate IT groups involved in a converged network are working together, it's not so easy to simply point the finger at the networking group or the applications group. It is imperative that the employees in your organization's different groups not only understand what the other is doing, but that they are also working in tandem and regularly communicating. Define specific roles for the applications group and the networking group and cross-train the employees. The two cultures may remain at odds, but they need to work together effectively.

"With a converged network, open communications is important. Usually, network and applications groups are separate in organizations. But an IP network forces them together," said Alvarez.

10. Investigate your vendor's support offerings. When you need help from your vendor, you need to be assured that you'll get what you need, when you need it. Choose a vendor that offers extensive online installation and configuration documentation; software and firmware downloads; online service request tools; and 24/7 phone support by qualified, technical engineers.

 

The Bottom Line

It's OK to start slow with a converged network, rolling out unified communications applications to a limited set of users. Establish these best practices in a small test environment, and you'll keep the initial deployment under control. And then you'll be ready to take the convergence across the enterprise.