December 1997

BY DARRICK FINMAN, EXCIDE ELECTRONICS

With the advancing integration of voice and data over a single network, computers have become more than business analysis machines and entertainment devices — they have become critical communications tools. Continuous connectivity is vital. Electrical power is necessary to operate the systems and devices that make email, faxes, video, the Internet, and telephony possible; however, power anomalies that would not make a light blink or a motor vary speed have the potential to totally disable a computer and corrupt data.

Depending upon the application, a disabled computer system can cost a business hundreds of thousands of dollars an hour. Computerworld magazine once put a price tag of $78,191 per hour on computer downtime for the average company, and the computer system doesn’t even have to protect an entire facility to be considered mission critical. For example, one information technology manager reports that a fif-teensecond power outage would take him off-line for two hours while he verified data. His computers serve a global WAN and are responsible for daily business transactions in excess of $16 million per hour. Protecting computer and network equipment from power problems should be a top priority.

KNOW YOUR NEEDS
There are several types of power protection equipment available, such as surge suppressors and line conditioners, but a UPS (uninterruptible power supply) is probably the most recognized category because it can provide both line conditioning and power outage protection. A UPS, depending upon its capabilities, offers basic protection for PCs to mission-critical protection for entire facilities.

Before deciding which UPS to buy, it is best to determine your needs. The best method is to conduct a professional power audit, especially if purchasing for a large LAN or entire facility. A power audit is a physical inspection of your site by a trained power engineer. The engineer analyzes key areas in your site to detect potential or ongoing problems. The data collected from the inspection will aid the engineer in determining the appropriate levels of power protection. Without a power audit, you might purchase more power protection than you need and incur unnecessary expense. You might also unknowingly purchase less power protection than you need, leaving critical equipment and data vulnerable to unexpected power problems.

UPS BASICS
There are three types of UPS topologies: standby, line-interactive, and online. Standby UPS: Also known as offline, these are a good solution for less critical applications (like a PC or fax machine) because power voltage and frequency changes are not regulated. Only limited protection is offered against power sags, frequency variations, and brownouts. In many cases, these inconsistencies are passed to your system. Standby models do offer enough back-up time (approximately five minutes) in the event of a complete power failure to allow you to save work in progress and properly shut down the system.

Line-Interactive UPS: These also provide basic power protection like standby models, but have more voltage regulation capabilities. Lineinteractive systems regulate voltage by using a transformer to step up or step down the utility voltage during brownout and overvoltage conditions. Some lineinteractive designs use the internal UPS batteries to provide power during transformer switching, reducing the useful life of the battery. Selecting a lineinteractive UPS that minimizes battery use in normal utility voltage corrections can save you money in the long term. Line-interactive designs also frequently provide a higher level of communications support than standby products, and are ideal for workstations, LAN servers, and internetworking equipment. These systems are usually sensitive to utility voltage swings and can benefit from power management software for power monitoring and automatic system shutdown.

Online UPS: This type of UPS provides the most comprehensive power protection and, often, the most robust communications and network support. Online technology replaces utility power as the primary source feeding the load by converting the utility AC voltage to tightly regulated DC voltage and then electronically “synthesizing” continuous, clean AC power. This topology eliminates AC power disturbances, transients, and frequency fluctuations from reaching your critical systems and provides steady, continuous power regardless of the condition of the utility voltage. Online designs often have a wider tolerance for utility voltage changes and can compensate for most sags and overvoltages without using the internal UPS batteries. Online UPS products are the best choice for applications where availability, maximum uptime, and long-term reliability are key concerns.

DISTRIBUTED COMPUTING
Many distributed computing systems, no longer the realm of simple information exchange or e-mail, are running the mission- and revenue-critical applications that were once the exclusive domain of the mainframe. Protecting valuable data running through networks is one of the most important issues facing network managers. Contingency Planning Research says that over 45 percent of accidental data loss can be attributed to power anomalies. Simply put, network downtime can seriously impact a company’s bottom line. According to a 1993 study by Infonetics Research, Inc., if each segment of a 30segment LAN is down for only 1.5 hours a year, an organization can lose up to $7.5 million in productivity and revenue. Network power management is a valuable tool in helping maintain network availability and in protecting critical information. Through remote monitoring and other advanced features, network managers can monitor power for an entire organization through one workstation. In some higher-end packages, remote retrieval of battery information is also possible, making planning for UPS maintenance much easier.

MANAGING POWER DATA
Power management data can be obtained several ways. A basic method is through contacts within a UPS, or relays, which provide enough information to initiate a shutdown sequence. However, an RS-232 link between the UPSs and computer is the most commonly used method today. More sophisticated UPSs can also communicate on either Ethernet or Token Ring networks. Software provided by the UPS manufacturer activates the power management capability within the network.

Although many UPS vendors provide proprietary software to fully leverage their product’s capabilities, leading manufacturers have worked together to create a standard Managing Information Base (MIB) that allows a mix of UPS products on the same network to communicate via SNMP (Simple Network Management Protocol). Some manufacturers provide an extended MIB that can be loaded onto the network management software package to provide the full information capable within their UPS. Power quality information, UPS operational status, and UPS control can be obtained and used to increase system availability.

Sophisticated software packages provide notification via SNMP traps. A trap is a message which is sent to an SNMP-supported network management software package (such as IBM’s NetView, Hewlett Packard’s OpenView, and Sun Microsystems’ SunNet Manager) and contains a brief statement describing a particular power condition and a command that initiates a particular action. A network manager receives information in a form consistent with other network related messages. Comprehensive power management software can:

• Respond to SNMP requests.
• Generate SNMP traps.
• Display data from all or any combination of UPS systems on the network.
• Perform automated unattended shutdowns.
• Create power log files.
• Generate power quality reports.

Today’s network power management software products, whether basic or sophisticated, all provide for graceful shutdown of the operating system and closing of all open applications and files in the event of an extended electrical failure, thus protecting critical information from loss or corruption. They also provide configurable shutdown parameters, which allow users to allot battery time prior to beginning the shutdown process and turn off the UPS, preventing complete battery discharge, which dramatically shortens battery life. By choosing a more sophisticated package, a shutdown sequence may also be customized to execute a particular command prior to bringing down the system. This feature will close less critical functions in a userdetermined priority order.

By using a network power management software package, a network manager can remotely monitor and control a UPS, perhaps initiating a remote reboot, a function sometimes necessary to maintain operations. Remote monitoring provides global control of a UPS and protected equipment. Communication with network adapter products is also an option. Network adapter products connect a UPS directly to a network and protect non-computer devices such as hubs and routers. More advanced software packages also permit communication with adapters, allowing one UPS to power multiple computers. Power management software also provides both manual and user-defined battery tests for each UPS on the network.

CONCLUSION
Understanding total network needs and making an informed purchasing decision are the two most important factors when selecting a power management solution. Power protection must not be viewed as a mere expense, but as an investment in availability assurance. Purchasing a lowcost power management solution may lower your initial investment, but could increase costs over the long term. The cost of losing critical data or replacing systems are far greater that the investment you’ll make in any UPS solution.

Darrick Finan is director of product marketing for Exide Electronics’ Network and Communication Systems Groups. Headquartered in Raleigh, NC, Exide Electronics provides Strategic Power Management solutions to a broad range of businesses and institutions worldwide. Exide Electronics’ products are used for networking, financial, medical, industrial, voice and data communications, military, and aerospace applications — wherever continuous power is essential to daily operations. For more information, visit the company’s Web site at www.exide.com

BY ANDREA LIGHT

There are a variety of power problems that can affect a network. According to a Bell Labs study, surges and spikes account for 7.4 percent of power abnormalities, with blackouts at 4.7 percent, overvoltages at 0.7 percent, and sags and brownouts accounting for 87 percent. These statistics demonstrate why all sectors of a network must be protected with a quality uninterruptible power supply (UPS). Any part of the network that is responsible for transmitting data is particularly susceptible to these power problems. This includes mission-critical servers in addition to internetworking devices of a network, including hubs, routers, gateways, switches, workstations, and telecommunications equipment. A complete power protection strategy goes beyond attaching a UPS to all data transmitting devices. With advanced diagnostic and power management software being offered by some UPS companies, your power protection strategy can not only protect your hardware and data, it can help manage the network. These software packages are typically compatible with the major server operating systems such as Microsoft Windows NT, Novell NetWare, UNIX, and more.

Power management software provides you with the ability to plan for and control crisis situations that may occur due to power problems. Power outages can often last longer than the runtime of the battery in the UPS. During these extended power outages, the software will automatically close open applications, ensure the data is safely stored, and initiate a graceful system shutdown before the batteries’ power is exhausted. The software also gives you the ability to schedule system shutdowns, UPS self-tests, provide for automatic reboots, receive notification of power events, and customize the UPS response to specific events. In many cases, the software is often included as a standard offering with the UPS, at no extra charge.

Protecting The Telco Closet
This type of power protection and management is just as important for telecommunications as it is for standard network equipment. Most companies today heavily depend on the telephone to conduct day-today business. As with computing downtime, power problems are often the culprit of telecom equipment downProtect Your Network Or Pay The Price time as well . If the phones are down, the business is losing money. When a power problem corrupts data or causes a computer-based telecom system to freeze or hard-crash, the cost of downtime and recovery can range from several thousand dollars per hour up to $120,000, for a telecomintensive catalog sales company.

Just as you would add UPS protection to the server in a network, you should also add UPS protection to your key systems and PBXs in the telecom closets. Incorporating power protection on these systems gives operation managers the assurance that calls and data being transmitted through the equipment are free from corruption and that hardware is protected. To ensure maximum uptime, a UPS should be used to protect all the key components of telecom systems, not just the PBX. Such critical components include voicemail systems; telecom peripherals such as CSUs, DSUs, and multiplexers; and PCs being used to monitor call centers.

Server Based PBX
Today, much of the standard telecommunications equipment is becoming PC and server based. We see this industry move in voicemail systems, call monitoring systems, and even PBXs. Another great example is the Server-based PBX (one or several PCs running on standard operating systems such as NT and UNIX, carrying out the functions of a PBX). Although the technology of computer-telephony integration (CTI) is without a doubt making the task of telecommunication management much easier, it also opens the door to issues such as data loss, hard crashes, and system lock-up, just to name a few.

With the emergence of this technology and the convergence of data centers and phone systems, power protection is crucial to minimizing data corruption, downtime, and system failures. Furthermore, power management through software is now possible in the telecom world thanks to computer-based systems. The same power management software used to control a UPS that is protecting standard computing equipment can also be used to control a UPS that is protecting computer telephony equipment.

Choosing Wisely
When choosing a UPS for protection of telecommunications equipment, several factors should be taken into consideration. To ensure customer service is continuously being provided to your customers, telecommunication systems running your company’s call center may, in some cases, require a higher degree of availability than some servers. In such cases, an extended-run UPS can increase your runtime to several hours simply by attaching additional batteries. Another attractive option is available with many UPSs which allows the user to replace batteries while the system is up and running. As in today’s server environment, much of the equipment in the telecommunications arena is moving off the floor and into racks. To address the limited space issue, many UPSs are available in rackmount form, and some offer an extendedrun enhancement.

Another desirable feature to look for is a UPS with dual output voltage. With many PBXs requiring 208 Vac input and the peripheral equipment requiring 120 Vac input, a dual output voltage UPS, which provides both 208 Vac and 120 Vac, eliminates the need for multiple UPSs. Several UPS companies also offer various accessories that allow customization of UPS power management. Simple Network Management Protocol (SNMP) adapters give you the ability to manage your UPS from your network management station, permitting such actions as remote UPS shutdown, reboot, and diagnostic monitoring. Other accessories provide the same management capabilities via modem, as opposed to SNMP.

Devices to monitor ambient environmental conditions, such as humidity and temperature, are also on the market. By using such a device in conjunction with power management software, graceful system shutdowns and administrator notification can be initiated when temperature limits exceed user configurable thresholds. Some UPS companies even offer modules which integrate full UPS control into dry contact environments. This type of control is ideal for PBXs, telecom management systems, and building security and alarm management systems.

In summary, power protection should be included as a standard part of both your company’s computing network and telecommunication systems. Power management software and accessories can greatly increase and enhance the UPS functionality and manageability. With the correct power protection strategy, your business will receive increased systems uptime and reliability and will aid in improving a company’s overall contingency and productivity.

Andrea Light is associate product manager at American Power Conversion (APC). APC designs and manufactures uninterruptible power source systems, surge suppressors, and accompanying software which provide pure power to computers, engineering work stations, phone systems, file servers, Internet equipment, and any application that demands clean, steady power. For more information, visit the company’s Web site at www.apcc.com