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The benefits of IP telephony will be greatly reduced to the point where the entire implementation could be jeopardized if proper power and cooling support is not provided for IP telephony equipment. In the data center, this equipment may already be protected by online uninterrupted power supply (UPS) systems, be precision cooled, have physical security, and be monitored and managed by an internal IT staff that can provide immediate attention in the event of a problem.

IP telephony equipment in remote wiring closets, however, is typically less secure, less protected and far more apt to be at risk from higher repair times. Accordingly, IT managers should consider the complete protection required to provide a high-availability system.

To its users, an IP telephony system should offer the same level of availability as traditional telephone systems. Downtime that may be tolerable for a data network is intolerable in an IP telephony system because of the convergence of critical applications for data, voice and video. Protection of such systems goes beyond just having a UPS.

For power availability and protection, integrated systems are now available that are tailored to the needs of IP telephony equipment outside the data center, ensuring protection while simplifying deployment. For heat removal, a choice of ceiling-mounted, precision cooling systems or sealed enclosures with integrated cooling is available.

Existing online, double-conversion UPS systems that offer continuous availability are almost always used to protect key data centers and the IP telephony equipment installed there. Intermediate distribution frames and wiring closets in remote locations, however, where IP telephony equipment is located, often are protected by line-interactive UPS systems to ensure power quality. These UPS systems may provide reasonable protection for some applications but, when used for IP telephony, they increase the risk of unexpected shutdown and packet loss.

Depending upon the system architecture, IP telephony systems may be more concentrated than traditional systems. With IP telephony call-management components at the headquarters level, the entire distributed organization can become vulnerable to power problems that affect the headquarters-based components.

The six requirements for ensuring the high availability of IP telephony systems are:

Power quality. While line-interactive UPS systems are cost-effective technology for less-than-critical applications, they cannot protect vital network systems from subtle, but common, power disturbances. IP telephony systems should be protected across the network by online, double-conversion UPS systems or DC-based UPS systems.

DC-based systems are emerging as an effective power alternative for IP telephony protection. These systems deliver reliability and power quality and are cost-effective in large enterprise deployments.

To ensure power quality, the power protection strategy should be mapped to the entire IP telephony system–desktop, intermediate distribution frame, main distribution frame and data center. Organizations with multiple offices should include collection points for each facility. An expert in power protection and configuration can help evaluate each site for potential threats.

Also important is determining how the IP telephony system architecture fits or does not fit within the current IT infrastructure. The IP telephony deployment can create an opportunity to review the current network protection scheme to determine if vulnerabilities have been created as network requirements outgrew protection system capabilities.

Uptime and redundancy. IP telephony systems require greater power backup than IT data networks to ensure communications are functional throughout a prolonged outage. Moreover, power protection should be scaled to match the system’s redundancy.

Most UPS systems are designed to keep systems up and running long enough to ride through brief outages before conducting an orderly shutdown or transferring to generator backup–usually six to10 minutes. Even extended battery cabinets rarely provide more than 15 minutes of backup. IP telephony, however, may require more battery time, especially if there is no generator backup. Three or four hours are not uncommon.

Rack-mounted, double-conversion UPS systems can have backup times of up to four hours. Beyond this, identifying additional approaches to availability is more effective, including power feeds from other utilities and backup generators.

There are multiple ways to match UPS protection to system redundancy. One way is through the use of dual UPS systems and power distribution within the network enclosure system. Another method is to employ a UPS with built-in redundancy. The appropriate method depends in part on the scale of the system, and the costs and benefits of the different protection strategies.

Precision cooling. IP telephony equipment is often installed in areas such as wiring closets, which traditionally lack precision cooling. The addition of IP telephony equipment to other areas, such as data centers and main distribution frames, may also require additional cooling. Every remote location for IP telephony equipment should have a temperature sensor to prevent potentially damaging increases in temperature.

Monitoring. IP telephony equipment and power and cooling protection require 24x7 monitoring regardless of their location. Every piece of power and cooling protection should have appropriate communications software for remote, Web-based monitoring and management.

Physical security. While remote components of an IP telephony system can be monitored and managed from a central location, portions of an IP telephony system are often located in areas without lock-and-key security. They should be housed in a lockable enclosure, accessible only by approved personnel.

Mission-critical service. Before purchasing power and cooling protection, consider who is going to be maintaining it and how quickly they can respond. Having local service and support that is knowledgeable about IP telephony, and power and cooling protection, is critical. Equipment also plays a role in making repairs easier. For instance, a maintenance bypass switch for the UPS lets service personnel make repairs to the UPS without shutting down IP telephony equipment.

Expectations for high availability of IP telephony systems take power protection to a whole new level. Designing and implementing protection for IP telephony is not a simple process, and the biggest mistakes are in assuming that existing IT network protection will work for IP telephony systems and that a UPS is all that is needed.

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