No matter what size network an enterprise is running these days, large and small alike are faced with increasing technical and financial challenges. These include dealing with a myriad of networking components, never ending security issues, the unquenchable demand for new network services -- such as Voice over IP (VoIP) and IP television. Along with balancing this demand is the ongoing pressure to reduce capital and operating expenses. Increasingly, enterprise CIO’s are deciding to outsource the operation, support and maintenance of their enterprise network to a third-party. The driving force behind this shift is new market innovations, such as the convergence of voice and data, which makes network operations more complex.

The term “Hosted VoIP” means a number of different things to different people. One key data point is that the “who” of hosting should be transparent to the end user. It can be a service provider or a third-party offering the hosted solution. The hosting can be offered in a completely separate facility sometimes called a Global Network Operations Center (GNOC) or can be offered directly on the carriers’ or their customers premises. One key point is that whoever is providing the hosting actually owns the equipment and this in-turn significantly reduces the amount of CAPEX for the Enterprise. Enterprises will ultimately choose the optimized hosted solution based upon their own network needs, core technical competencies and capabilities as well as desired services.

While the hosting infrastructure architecture can be designed in a variety of ways technically, one of the parts of the decision process is who should perform the hosting. Obviously an enterprise needs to carefully select a trusted partner. Just as any outsourcing decision, handing over an important function of network operation needs to be a well-thought out process. Enterprises need to take into consideration the performance record of their partner, their partner’s commitment to new services development and deployment, as well as their customer support and business continuity and disaster recovery plans.

For many enterprise CIO’s – especially those involved with large enterprises – outsourcing on a scale this big might be considered a loss of control and a decision that could compromise overall quality. However, as technologies such as VoIP continue to evolve to new and even more challenging applications, it may be easier for enterprises to keep up by using a third-party provider.

New technology introduces complicated technical issues and VoIP specifically has two very relevant concerns that need to be addressed immediately -- security and quality of service (QoS). Both of them can be addressed in the network, however since both continue to evolve on a sometimes-weekly basis, they can become very cumbersome issues. This makes it quite difficult for an IT organization, that is already over tasked with regular network issues, to identify and resolve without significant investment.

The industry often chooses to focus on the positive features of VoIP — shared IT infrastructure, and plug-and-play adaptability. While these key elements take advantage of the flexibility of IP they are also what make it more susceptible to possible outside attack. Unlike a traditional circuit based telephone network, a VoIP network is vulnerable to the typical IP infrastructure issues, including interference from denial of service (DOS) attacks, viruses and worms. These attacks can lead to the major outages that sometimes occur with data networks – taking the network down for hours or even days.

There are also a variety of attacks that specifically target VoIP networks. Two recent examples include Spam over IP Telephony (SPIT) and malicious transmissions of obscenities. All of these issues would be a significant problem inside a corporate network – especially when they can lead to the disruption of phone service, which remains a mission critical application for enterprises.

In today’s fast-paced global business world many employees spend hours on conference calls and reaching out to customer and colleagues by phone. The ability to pick up a desk phone and have it work almost 100 percent of the time is taken for granted. However, with a VoIP network there are not the same guarantees. Because they are vulnerable to outside influence, these disruptions can magnify some of the other common deficiencies with VoIP – latency, dropped calls or distortion. Since voice communications is one of the most reliable and personal ways to conduct business most companies do not tolerate downtime on a voice network or unintelligible calls the same way they might with a data network or a mobile phone.

So what is the upside? The good news is that VoIP has been around for a number of years, so some of its major risks are well understood. The industry is constantly developing best practices and tools and techniques for protecting and controlling VoIP networks. For instance, the International Organization for Standardization offers ISO 17799, which provides recommendations for information security management, and also provides a common basis for developing organizational security standards. Similarly, the International Telecommunications Union’s X.805 standard, pioneered by Bell Labs, defines security architecture for systems providing end-to-end communications. And NRIC, the Network Reliability and Interoperability Council, provides best practices guidance in a number of areas that relate to VoIP operations.

While the tools to deal with security concerns and VoIP exist, the time it takes to implement them may be the harder part of the equation. Because the industry is constantly evolving, security issues may pull away hours and hours of resource time from already strapped IT Staffs.

Even the creation of a best practices model for an individual company is a laborious process. Typically this includes both an internal review that involves a detailed assessment of users such as administrators, managers and other employees -- as well as the more traditional security equipment assessments to show potential technical security gaps. A well-devised security plan must be able to include these unforeseeable risks and minimize them – however finding the time can be the trickiest part. In a hosted environment much of this work, especially keeping current with new types of attacks and solutions, will already be addressed.

The second major issue that is also commonly overlooked in the zealous race to move to a VoIP network is Quality of Service (QoS). While QoS has long been discussed in data circles, when an IP network is carrying real-time voice traffic QoS becomes an even more critical element. Just as planning is a key aspect to controlling the potential security issues; planning and network design are the foundation to building a VoIP network that delivers upon quality expectations. A good network design includes prioritization, traffic engineering, a plan to handle voice in a converged network and a restoration process.

In addition administrators must put a Call Admission Control (CAC) process in place. CAC allows the customers to properly design the network to carry the traffic load even at the busiest times while still meeting QoS objectives. This complex process can be managed, for the most part, by using one of the following methods: per call bandwidth reservation, local measurement based management, path-based management and link-based management. A network engineer needs to carefully consider each choice, because the incorrect decision can have a direct negative impact on total voice quality.

In a traditional circuit based network voice is given a dedicated bandwidth allotment so the quality is assured. In a packet environment a customer must either predict voice quality in a new VoIP deployment or assess voice quality in an existing network to ensure end user satisfaction. Both scenarios can be managed by using a well-designed modeling process. One way to accomplish this is to combine both subjective testing with objective testing models. The subjective category includes the E-Model scale of user satisfaction categories (ITU G.109) that set definitive end values and give a Mean Opinion Score (MOS). The objective components then measures network impairments -- such as delays, packet loss and echo -- and computes a total score. In the case of a brand-new network, these models are then combined with a Network Performance Prediction Tool (NPPT) that takes into account network information, VoIP traffic demand patterns and a Network Performance Prediction algorithm to deliver a VoIP Voice Quality Prediction Report.

In the case of an existing network the E-Model testing is still used for a Voice Quality Assessment portion, but it is combined with other assessment tools such as Network Discovery, Network Performance Measurement, Delay Assessment Plan, Delay Assessment and Root-Cause Analysis to deliver a VoIP Voice Quality Assessment Report. While the industry has a number of different approaches to QoS it is clear that voice quality is key to the ultimate success of a VoIP deployment. The planning and traffic prediction make or break the deployment. The use of a hosted environment where detailed planning was built into the VoIP platform and network design, and which will continue to be upgraded and monitored as new technology emerges, may make a significant difference in overall performance – whether its technical, commercial, or both.

Given today’s competitive operating environments, the benefits of the hosted model provide some compelling reasons to consider it as a viable option. These may include lower overall operating expenses, ability to provide enhanced security, improved network performance and capability to quickly rollout new services such as VoIP. This approach allows enterprises to focus on their own core network competencies and redeploy staff to areas that make the most use of their expertise.

As VoIP and a wide variety of other broadband communications applications - including unified messaging, security and mobile extension applications that can extend the functionality of the office phone system to a mobile environment - continue to emerge on the scene, the network landscape is dramatically changing. The continuous push to add new technology is tipping the scales in what was once a closely guarded possession for organizations -- network operation. When customers combine the cost-effectiveness and the ability to immediately offer new services the decision to outsource is becoming clearer every day to both the network operator and enterprise CIO.

Rob Falkner is director of hosted and managed applications & managed Services for Lucent Worldwide Services.

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