By Jeff Lupinacci, RCDD, DCDC, Mission Critical Partners Inc.
Workstation congestion does not refer to a cold or allergy, but rather to the increasingly claustrophobic growth in items co-located with the workstation occupant. In a public safety answering point (PSAP), the number of systems and devices seems to be continually increasing, making it hard to access devices, cables, and connections for maintenance or service. The original installation may be neatly laid out, installed, and look just fine; but over time systems and components are added. Congestion also reduces the amount of space available for devices and reduces the capacity for cables. These new or replacement devices may not fit as well as their predecessors, nor are they installed with the same degree of cable management.
Just to understand what items contribute to this issue, let’s look at the components that are installed in a typical telecommunicator position.
The workstation console furniture is the first item installed, and is the foundation to support all devices and cabling for the position. These vary by manufacturer, but most have items that include table surface lifts, lift controls, personal lighting and their controls, personal heaters and ventilators and their controls. Each of these items has cables for power and control that take up space, and require interface with some of the building systems. Also installed is a standards-compliant grounding subsystem grounding busbar (SSGB) and grounding conductor, #6 AWG (American Wire Gauge). The life system, lights, heating/ventilation/air-conditioning (HVAC), and other items are powered by a separate power circuit from the sensitive electronics, and not on the uninterruptible power supply (UPS). Prior to completion of the workstation furniture, the installer needs to add the power, telecommunications, and radio connections that will support the devices at this telecommunicator position.
Causes of congestion
The number of cables needed for network connectivity is more than you would imagine. The number increased even more since the systems provide an evidentiary record of all activity for the logging recorder to store for subsequent retrieval and review. Systems connect to other systems, and data is exchanged as the next generation 9-1-1 (NG9-1-1) compliant system is installed.
Located at the workstation is a computer system that runs the computer aided dispatch (CAD) software, that usually will have multiple 24-inch monitors to provide data entry space, suggested response information, responder unit status, etc. These systems often provide global information system (GIS) data, or mapping of the location in question, with layers of mapped data to help with the dispatch, or to provide the first responder with data to support them in their mission. The data can be anything from fire-hydrant locations, to power-transformer locations, to boundaries between ambulance companies or other response units. In addition to the computer itself, there is a power cord, multiple monitor cords, keyboard cord, mouse cord, audio cord, and one or two network cables.
Another system located at the workstation is a computer system that runs 9-1-1 telephone software or customer premises equipment (CPE) software. This system uses Voice over Internet Protocol (VoIP) to digitize, transmit and decrypt voice communication. The CPE system usually has a single 24-inch monitor, and an audio connector for the supervisor to listen in. The user connects to the system with a handset and/or a headset to speak with the caller. Often dedicated external keypads, similar to those made by Genovation, are provided to allow the user to access features and dial numbers with ease. The call data or ANI/ALI (automatic number information/automatic location information) along with an audible recording is sent to the logging recorder. So in addition to the computer itself, there is a power cord, monitor cord, keyboard cord, keypad cord, mouse cord, audio cord, headset connection, supervisor audio connection, and one or two network cables.
Another system located at the workstation is a computer system that runs the radio console software. This system acts as a “remote control” for remotely located radio equipment and gives the dispatcher the ability to speak on various radio frequencies with the click of a mouse. The radio console system usually has a single 24-inch monitor. The user connects to the system with a handset, microphone and speakers, or a headset to speak with the responder. The radio transmissions are also sent to the logging recorder as part of the record of that call. So in addition to the computer itself, there is a power cord, monitor cord, keyboard cord, mouse cord, dual speaker cord, headset connection, microphone connection, and one or two network cables. Some PSAPs also place a mobile radio at the position as a backup to the radio console. This would add another power supply, and antenna cable to that workstation.
If that were not enough, most workstation positions also require one or two computer systems for normal business applications like e-mail, Internet access, etc. These workstations may also be used for weather-status reporting, and closed circuit television (CCTV) monitoring for situational awareness. Some PSAPs allow users to watch television programs or do online coursework during slow periods. Each of these systems will add power cords, monitor cords, keyboard cord, mouse cord, and network connectivity-taking more valuable real estate and causing more congestion at the workstation position.
First step in congestion relief
With all these systems, the number of keyboards, mice, and monitors add up quickly. In order to reduce the number of interface devices on the work surface, a KVM (keyboard, video, mouse) switch is used to allow a single interface device to control multiple computer systems. The KVM provides a reduction of cables from the systems cabinet at the workstation to the work surface. In addition to the KVM itself you will need to buy a KVM cable for each system connected to; be sure to verify the connector types and cable lengths before purchase. Based on the number of systems that the KVM can support, the resolution of the monitors, the speed of the USB connectors, expansion capability and other features, a KVM can cost between $200 and $700. Some KVMs are sophisticated devices that need firmware upgrades, and device drivers installed to make full use of the features.
This is not new technology, but they are increasing in their functionality as the market moves to faster interfaces, higher-resolution monitors, and greater densities. One difference between the PSAP market and the data center market is that the PSAP user does not want to switch the monitors to a single active monitor at a time. Rather, they want to see all monitors, and switch between them with a single mouse and keyboard. The higher-priced KVM switches will allow you to configure them so your mouse will roll from screen to screen in one continuous movement.
Advanced congestion relief
Recently the concept of remotely locating the computer systems away from the workstation console furniture is being discussed. This basically places the computer system’s central processing unit (CPU), or the box, in a rack in the computer room away from the PSAP, then extends the devices that the user interfaces to the workstation console for them to use.
There are some really positive reasons why this should be considered. Some of the benefits that the PSAP hopes to gain are the following.
- More security for their system
- Computer systems located in a cleaner environment
- Computers are provided proper environmental conditions (cooling, power, grounding)
- Reduces noise and heat at the workstation console furniture
- Reduces the amount of power (not number of power connections) used at the workstation console furniture
- Centralized computer system maintenance (requires local monitor, keyboard and mouse)
But not everything that sounds good is without drawbacks. Some of the communications types were designed to connect directly to the computer system, and not intended to drive the signal a long distance. Their drive distances refer to the linear meters (or feet) of cable over which the signal can be transmitted. This is not the same as the distance a “crow flies.” Some limits are listed in the table.
The signal drive distances begin to limit how far you can place the interface devices from the system’s CPU. Specifically in the PSAP environment we want to extend all the high-resolution monitors to the workstation, rather than one like in the data center environment. If your environment will allow cables to be placed that fall into these distance limitations, then it can be a very clean installation. But if the layout requires cables to exceed these distances, it would require active components to overcome this problem. Active components can be purchased to extend these signals a much greater distance, however they need to have a receiver that will translate it back to the original signal for the end device (monitor, USB connection, audio speaker, etc.).
The active components are available in pairs with one side (computer room) being the transmitter (Tx) and the other side (workstation) being the receiver (Rx). A local output provides a connection to a monitor in the computer room that will allow a service technician the ability to see what is happening on the system for troubleshooting.
Currently the amount of information that needs to be transmitted over a standard Category 6 unshielded twisted-pair (UTP) cable limits one monitor to one cable; and some manufacturers recommend using Category 6A shielded twisted-pair (STP) cables for high-resolution monitors. The active components needed to drive the signal require power at both ends, usually a power supply with a low power draw. Therefore we need to place Rx equipment (per monitor and for each device) at the workstation console position, power it and provide a connection back to the computer room. At the computer room end of the connection we will need to place the computer systems in a cabinet, provide the Tx components, power supplies, and cables to drive the signal. We have found that the equipment needed will limit the number of positions per cabinet to two.
There is a substantial cost to relieve the workstation congestion, without totally eliminating the equipment needed to accomplish it. The increases include the following.
- Computer room floor space (highest cost/square foot)
- Computer room cabinets
- Additional power distribution in the computer room (power supplied to cabinets)
- Additional cabling (patch cords to extenders, workstation drops)
- Local monitors, keyboards, mice, KVMs, and KVM cables to service in the computer room
The additional cost to remotely place the computer system amounts to approximately $10,000 to $12,000 per telecommunicator. This cost is not unmanageable, but realize that the resulting installation will only partially meet the goal of all equipment in the computer room. This solution will also introduce additional points of failure to your workstation electronics.
Jeff Lupinacci, RCDD, DCDC is project manager and technology specialist with Mission Critical Partners Inc. (www.mcp911.com).