16. Industry History That Can Predict the Future
Chapter objectives
1. Get to Know the Basics in the Chapter Overview
2. Learn about the First Generation
3. Understand the Second Generation
4. Learn about the Short-lived Third Generation
5. Learn How the Industry Matured in the Fourth Generation
6. Learn Why the Future Is with the Fifth Generation Systems
7. Answer Questions about How Access Control History Affects Design, Installation, and Maintenance
CHAPTER OVERVIEW
There have been five generations of Alarm/Access Control Systems. With each movement from one generation to the next major changes in architecture and capabilities occurred. If one looks through the lens of history, one can see into the future through the pathway the industry has taken.
From the first generation to the fifth, there have been major increases in capabilities. Although the fifth generation has yet to realize its full potential (and for many manufacturers this may never happen), the promise of current technology is amazing. By the end of this chapter you will understand fully the capability of the current generation's technology.
Much of the information in this chapter is derived fromChapter 3of my book Integrated Security Systems Design. For those readers who are interested in systems design, this book is a good reference manual.
There have been five generations of Alarm/Access Control Systems. With each movement from one generation to the next, major changes in architecture and capabilities occurred. If you look through the lens of history, you can see into the future through the pathway the industry has taken.
From the first generation to the fifth there have been sweeping changes in the industry. Although the fifth generation has yet to realize its full potential (and for many manufacturers this may never happen), the promise of current technology is amazing. By the end of this chapter you will understand fully what the current generation's technology will be capable of at some point in the future.
Much of the information in this chapter is derived from Chapter 3 of my book Integrated Security Systems Design, written in 2007. For those readers who are interested in systems design, this book is a good reference manual.
Keywords: Access Control, Alarm, Generations, History, System
Author Information:
Thomas L. Norman, CPP, PSP, CSC, Executive Vice President, Protection Partners International
A Little Background
In my capacity as a consultant, I am approached frequently by manufacturers who want to explain their wares. As I question them on the capabilities of their systems I am intrigued that most manufacturers are not even aware that their technologies have crossed a generational border, nor are they aware of what promise their new platforms can bring. Many manufacturers have adopted a “me too” approach to system development and do not seem to understand that in their efforts to “keep up” with the development of competing systems, they now possess a system capable of far more than it delivers.
As we go through this chapter, you will begin to see how to unlock the hidden capabilities of many systems on the market. Then you will be able to make your system do things even their manufacturers did not know they could.
Does history repeat itself? Does history draw a vaguely linear line into the future? Can we learn anything at all about our career if we know the history of how it became what it is? The answer to all of those is a qualified yes.
The history of the Access Control Industry has been one of continual consolidation into ever larger and larger companies held in fewer and fewer hands. To some extent this has been good for the industry, for integrators, and for clients. Has the technology gotten better? Most certainly it has. Does it do more? Yes it does. Is there that one system that can do everything? No, not yet. There are far fewer brands and models of Alarm/Access Control Systems on the market today.
Alarm and Access Control Systems are in most cases part of a larger Integrated Security System that includes Digital Video, Security Intercom, 2-way Radio, Photo Identification, Visitor Access System, and often other systems as well.
The Alarm/Access Control System was, for many years, the heart of all integrated systems. This is not the case today. Alarm/Access Control System manufacturers have abdicated their leadership role to the Digital Video industry, which is also not yet fully aware of what their systems can do, especially when coupled with a powerful Alarm/Access Control System.
The Access Control Industry has evolved, in my opinion, along a line that has served the short-term interests of the Access Control System Manufacturers well, but not the needs of the Integrators and their Clients. In the end, the Access Control System Industry, which should have been the focus of all system integration, has abdicated that role to the Digital Video Industry to the detriment of its clients, its integrators, and, ultimately, the Access Control System manufacturers themselves. The market always vindicates and often that happens with a vengeance.
In the end, the market share will go to the segment of the industry that provides the infrastructure for all other segments to operate under. That was the Access Control Industry. But increasingly, I believe it will be the Digital Video Industry.
First Generation
In the beginning, there were guards. Or rather, I should say, in the beginning there were Night Watchmen. It was up to the receptionist and office staff to control access, such as it was. In most cases, it was possible for a total stranger to walk right up to the organization's President's office with no one stopping to ask anything. Those were simpler times with simpler crimes.
However, as night fell and all employees went home it was left to a Night Watchman to conduct his “rounds.” He would walk around and through the building(s), looking for anything that was out of place. If he found an intruder, he would challenge him and sound a whistle that hopefully would fall on the ears of a police foot patrol.
The first McCulloh Loop telegraph-type alarm system was installed in Boston in 1882 (Figure 16.1). Later systems worked by sending a 20 milliamp current down a loop of wire and then monitoring the current on the wire. If there were any changes in the current, an alarm meter would change state or a pen would move on a paper tape, signaling a change in state in the alarm circuit. These were widely used in Police Call Boxes and Fire Pull Stations. The first magnetic stripe access control cards appeared in the 1960s. Early intercom systems date back to the 1877, one year after Alexander Graham Bell patented the telephone, 1 and were first used in Police Call Boxes. In 1961, the London police began using closed-circuit television (CCTV) to monitor activities in train stations. 2 All of these were discrete, individual systems. For example, there were no camera switchers, but each camera reported to an individual video monitor. Videotaping did not occur due to the expense. Alarm recording was done by hand notes and maintaining the McCulloh Loop paper tape.
1“From the Call Box to the Computer,” an ITI Whitepaper on the Changing Face of Technology in Law Enforcement, Information Technologies, Inc.
The first generation of Access Control Systems is still in use today, and is most often seen on Hotel Room Doors (Figure 16.2). These are stand-alone card readers, each one controlling a single door. Although unconnected to any other card reader, and therefore not part of a network, first generation Access Control Systems were a major step forward.
In the first generation of security technology, intercoms and CCTV were a rarity. CCTV systems usually comprised only a few cameras with each camera reporting to its own video monitor. There is a resurgence in First Generation Access Control systems, primarily using a biometric reader or keypad built into an electrified door lock. These are marketed to upscale residential and light commercial users.
Second Generation
The second generation of access control systems networked eight card readers together to a dedicated computer that was about the size of a huge early electronic desk calculator (Figure 16.3). 3 There were a pair of keypads (A–F and 0–9), a nixie tube display, and a 3-inch paper tape. When a person presented a card to the front door of a facility, you would hear the paper tape chatter and the nixie tubes would display something like 1CO3-AA. One would then refer to a book that would indicate that card CO3 was granted access to door 1.
3Examples of second generation access control systems include the Rusco® 500, the early Cardkey® 1200, and numerous Secom® systems.
The second generation of alarm systems replaced the impossible to read meters and paper tapes with colored lamps and (at last) an audible alarm (Figure 16.4). 4 Each alarm had three colored lamps: green for secure, red for alarm, and yellow when bypassed. There was a switch to bypass the alarms. The second generation began around 1945 and continues today.
During this time CCTV systems were still little used, but intercom systems were becoming only a little more than obscure.
Third Generation
The Third Generation of Alarm/Access Control Systems began in 1968 and continued until about 1978. For the first time, Third Generation Systems combined alarm and access control into one system (Figure 16.5). Up to 64 card readers and up to 256 alarm points were wired home-run style to a PDP-8 or IBM Series 1 mini- computer. These were often the size of a four-drawer filing cabinet. These computers often used core memory, a Beehive Terminal, and a line printer. A basic 16-card reader system could cost over a hundred thousand dollars. During this time, CCTV began to be used by corporations and there were a few instances of intercom systems.
 |
| Figure 16.5 |
Most commands were operated by a combination of keystrokes that the operator had to be trained to remember. Early Cardkey systems used so-called “dot commands,” wherein actions to be carried out by the system were initiated by the operator using a two-letter command preceded by a period (dot).
These were a far cry from later mouse-operated Graphical User Interface systems.
Fourth Generation
In 1971, Intel® introduced the first 4-bit microprocessor, the 4044, designed by Intel designer Ted Hoff for a Japanese calculator company. 5 The processor boasted more than 2,300 transistors and more switches than ENIAC. It filled an entire room and required a dedicated air conditioning system just for the computer (Figure 16.6). The 6502 and 8088 8-bit microprocessors soon followed. These were the basis for a new breed of Alarm and Access Control System Technology called distributed controller systems.
5Patent #3,821,715, IEEE Global History Network, Ted Hoff: Biography, http://www.ideafinder.com/history/inventors/hoff.htm.
Up until 1974, each alarm and access control field device was wired individually back to the mini-computer, where a jumble of wires fed into custom-made circuit boards. All that wire was costly and often cost-prohibitive for most organizations. In 1974, one of the first distributed controller microcomputer-based alarm and access control systems was christened. 6 For the first time it brought the ability to multiplex alarms and card readers into controller panels and network panels together into a distributed system. The system comprised a series of individual Alarm/Access Control Panels, wired together on a proprietary network, all connected to a central mini-computer. This was a radical change. Finally, the cost of wiring, which was a major cost of early systems, was dramatically reduced, although the first fourth generation systems still terminated all of those controllers into a central mini-computer, computer terminal, and line printer. 7 The computers often had what I like to call a “user-surly” interface. When a person presented a card at the front door, the terminal still dutifully displayed something like “1CO3-AA” as the line printer chattered off the same message. The console officer looked that number up in a book. The system still had a long way to go.
Corporations begin using intercoms and CCTV more extensively, although prices were still prohibitive for most users, with basic cameras costing as much as $1,200 each. 8 Major advances in CCTV occurred during this period as well. For the first time, it was possible to use just a couple of video monitors to view many cameras, as the cameras were finally terminated into sequential switchers that switched the monitor view from camera to camera in a sequence. 9
As the industry progressed, costs dropped dramatically and the systems became much more user-friendly. CCTV systems saw major advances. First, the advent of consumer videocassette recorders helped drop the price of video storage to practical levels. Toward the early 1990s, video was multiplexed by splitting the 30 frames per second that the recorder used between various cameras so that each camera was recorded two or more times per second onto a single tape. This economized video storage even further. In the Alarm and Access Control System industry, during this time, mini-computers gave way to PCs and Server-Based Networked systems.
The laggard was intercom technology, for which there was no single industry standard, little compatibility between manufacturers, and it was not generally friendly to networking between buildings or sites. Intercom usage was minimal in most systems, and usually reserved to assist access at remote gates and doors.
By the mid 1990s, however, the manufacturers realized that organizations wanted to integrate their various systems and began to integrate alarm, access control and CCTV, and intercoms into a truly integrated system. These systems could detect an intrusion, automatically call up an appropriate video camera to view the alarm scene, and, if an intercom was nearby, they could sometimes queue the intercom for response. They would also display the video and a map showing the area of the alarm to help the console operator understand more about what he was seeing on the video monitor.
These systems were able to detect and respond to emerging security events in real time. But the system interfaces were highly proprietary and clumsy. Achievement of an interface between any two brands and models of systems would usually not apply to any other brands or models. Each time integration was desired, it was always new turf.
Stalled Progress
Many leading consultants believed that true systems integration would be performed by alarm and access control systems. 10 But they were wrong. Significant progress stalled for over a decade from the mid-1980s until after 2000. There was a fundamental reason for this that goes back to the foundation of the industry. In the early days of fourth generation microprocessor-based systems, 64 kilobytes (KB) of random-access memory (RAM) cost over $1,000. 11 With memory this expensive, the founders of the industry solved the problem by putting the “personality” of the systems into Erasable Programmable Read-Only-Memory (EPROMs). This meant that the systems functions were totally defined by the contents of their EPROMs. For the most part, their functions were not very field-programmable. By the end of the 1990s, some of the leading systems had a seemingly infinite parts list, with a part for every function. This was because the industry had failed to change with the times. By the year 2010, it was possible to buy 4 gigabytes (GB) of memory for about $100.00. That means that one could buy over sixty thousand times the amount of memory for nearly one tenth of the price of the 64 KB of RAM from 1980. That is like getting a fleet of 747 airplanes for the price of a pizza! As the computer industry surged forward in capabilities and dropped like a rock in price, some consultants and integrators considered that the access control system industry was desperately trying to maintain its margins and was not generally implementing advances in system architecture. Accordingly, at the same time that microcomputer costs were dropping dramatically, there were arguably no significant reductions in access control system costs. The access control system industry was also hanging onto a long-term strategy of keeping their architecture as proprietary as possible while clients were increasingly asking consultants to design non-proprietary, open-architecture systems. This strategy was doomed to fail.
10Surprisingly, one of the earliest full integration platforms came from a small company in Branson, Missouri, named Orion Technologies (now Aegis Systems), who intended to create a universal front-end system that could control any combination of Alarm/Access Control Systems, Video Systems, and Intercom Systems. Other major video manufacturers quickly followed suit, leaving alarm/access control system manufacturers as systems to be integrated instead of as the primary integration platform.
Fourth generation Alarm and Access Control System architecture functions were defined by their physical attributes. They did what they did because of the programming attributes of the EPROM. Their functions were controlled by their physical environment. Key Strategic Principle: It is important to understand that good security is achieved by the ability to control the environment. Any device that cannot control its environment outside of what the product development designer imagined that environment to be is inherently limited in its ability to serve the needs of the client in controlling appropriate behavior. If you cannot control the environment, the environment controls you.
The fourth generation of Alarm and Access Control Systems was doomed by its failure to adapt to emerging trends of network technology and trying to hold tenaciously to controller-based systems. Enter the fifth generation.
Fifth Generation
The problem with Alarm and Access Control Systems was that their manufacturers thought they were making Alarm and Access Control Systems (you read that right). What they were actually making were Programmable Logic Controllers (PLCs), which were equipped with an alarm and access control system database. This is an important distinction because, in their failure to understand this, they clung to EPROM architecture. While EPROMs solved the industry's early problems of high memory costs, as memory costs plummeted the industry confined their systems to the functions that its designers imagined for each box and implemented into the EPROM in the controller box. But corporate and government clients all had special needs that could only be met with changes in the logic structure of the controller. For example, if a client needed a local alarm to sound at a door if held open too long during the daytime, but wanted that door to alarm at the console immediately after hours, the client was sold an adapter box to perform that function for each door. Most manufacturers responded to such needs by building an endless list of adapter boards and boxes to make their system perform each unique need. For those manufacturers who did not make an endless assortment, there were third-party manufacturers who did.
This strategy served the manufacturing community well, but not the clients because of the additional hardware and custom equipment required to perform perfectly logical functions needed by the average client. For example, if a client wanted to have confirmation of perimeter alarms by two detection systems (requiring both to trigger to cause an alarm, but using each individually to cause an alert), most fourth generation systems required each detection system to have its own inputs (providing the alert: the “or” function), then the system would reflect the status of those inputs on output relays that would then be hardwired together to create “and” functions and those hard-wired outputs would be wired to additional inputs as “and” function alarms. This may not sound like a challenge, but for perimeter systems comprising fifty or more detection zones in each detection system, the cost of hardwire and wiring often ran thousands of additional dollars over what a PLC-based system would cost.
But a few industry experts understood that there is no function desired by any client that cannot be met by a simpler, not a more complicated, system architecture. Every imaginable function can be met by a simple combination of inputs, outputs, memory, logic cells, counters, and timers. Like dancing, where endless variety can be achieved with only a few basic steps, so too can an endless variety of functions be achieved with only these few basic logic objects. That structure defines PLC architecture. A few manufacturers introduced PLC-based alarm and access control systems, notably those who made Building Automation Systems (BAS) that were already based on PLC architecture. But these products never made a significant impact in the marketplace because they continued to focus their marketing efforts on their BAS product lines instead of their access control system products.
The key to fifth generation alarm and access control systems is that they are all based entirely on software-based functions (mostly Second Query Language, SQL) and reference databases, whereas earlier systems were based on functions that were defined in hardware. From the late 1980s through the 1990s, however, the industry was driven to integrate multiple buildings and sites together. The industry struggled with a variety of unsuccessful system architectures until it gradually adopted a network infrastructure already in place in most businesses — the Local Area Network (LAN), Municipal Area Network (MAN), and Wide Area Network (WAN) Ethernet architecture — already in use in their computer networks. As the manufacturers began adapting their systems to Ethernet architectures, a convergence of security systems began to occur, bringing together alarm, access control, CCTV, and voice communication systems into a single integrated system.
That convergence continues today. In its next phase, distributed alarm and access control system controllers may totally disappear as CCTV manufacturers realize that they can totally integrate alarm and access and intercom functions into their CCTV Ethernet architecture. This resulted in a system comprised entirely of “Edge Devices” (cameras, intercoms, door access hardware, etc.), and a server/workstation for the user interface. These are interfaced together on the LAN.
Today's digital video cameras are already appearing with Digital Signal Processing (DSP) chips and up to 64 megabytes (MB) of RAM. Soon, each individual door's access devices will be served by a single tiny controller in a junction box above the door. That tiny circuit board will comprise inputs, outputs, a card reader port, door lock output, and an exit device port, all served by a DSP chip and several megabytes of memory. A database of all users for that door will be contained in the DSP's memory board. A single centrally located controller may manage all of the microcontrollers in the entire building.
As these “Edge Devices” begin to connect directly to the LAN without an intervening controller, costs will drop dramatically. Although the industry seems terrified of this development, it will result in a substantially higher use of the systems. The industry need not fear this development. In the same way that CCTV manufactures feared the price drop below $1,000 per camera, only to find that camera sales soared, so too will alarm and access control and intercom sales soar as the introduction of microcontrollers causes prices to fall. When these devices are combined with PLC programmability, which will allow an infinite variety of applications without an endless stock of hardware, the industry will finally have arrived. Before the end of this decade, the industry will very likely be served by only “Edge Devices” and software connected together on a Security LAN.
Avoiding Obsolescence
Obsolescence is a funny thing. When we specify obsolete equipment, it does not seem so at the time. How can we tell what is going to be obsolete? How long is a good enough life cycle? What is the migration path to the future? There are signs.
Planned Obsolescence
At one time, a major access control manufacturer had in their current line five (count 'em 5) different access control systems. Each was designed to serve a different market growth segment from a small system that could support only about 32 readers to a large system that could serve multiple sites (sort of) and could handle thousands of alarms, card readers, and so forth. None of those systems could migrate to the next. If a foolish consultant were to specify a smaller system from this manufacturer, and the client outgrew that system in say, only two years, then the client would have to abandon much of the capital investment and purchase a new system. That is built-in obsolescence. That company does not exist anymore. It was bought by a big corporate integrator. It is their problem now. (Oh yes, and now it is their clients' problem, too).
Unplanned Obsolescence
The industry is undergoing a sea change as this book is written. Much of today's access control and video technology will not exist in any form before this decade ends. How do I know? From Market Forces, that's how. Some have argued that the industry has long been based on serving the manufacturers, not the clients. If that is true, Information Technology based systems will largely end that. It is possible that someday the industry will manufacture edge devices and software and nothing else — no digital video recorders (DVRs) and no access control panels, nothing but small microcontrollers and digital cameras that connect field devices directly to and powered by the Ethernet, oh yes, and Software. It is a good bet that all of those bent metal boxes that manufacturers love to sell will be obsolete soon. This is about to become a very thin market with very few manufacturers (but with lots of software vendors early on).
What the Future Holds
When I wrote Integrated Security Systems Design in 2006, I predicted that the Alarm/Access Control System industry would universally adopt something that none of the manufacturers offered at that time. I introduced the idea of microcontrollers to the industry. These are small, single- or double-door controllers that sit above a door, controlling that door only and having enough memory to store all of the users for that door and all of the functions needed at that door. Each microcontroller would communicate via TCP/IP to its host. This has now come to be. Today, many manufacturers offer microcontrollers.
I also predicted that microcontrollers would include a small four-channel digital switch used to connect one or two digital video cameras, an intercom, and another microcontroller down the hallway. So far no one has introduced that, but I still think it will happen because the market wants it.
You can create any function imaginable if you combine inputs, outputs, card reader interface, counters, timers, and access to the status and functions of all the system's software. I recently had a client request that the security console officers have no access to highly sensitive central bank counting room cameras when counting is under way and then regain access to those cameras when counting hours ended. We were able to accommodate an automated password function for the security console officers that automatically disabled and enabled access to the counting room cameras based on the hours of operation of the counting room. That is a powerful function.
I had another client request that when a computer programmer arrived late at night to work on an end-of-month database problem that lighting could be enabled to the server room and workstations area so that the programmer (often a lone female) would not have to transit all that distance in the dark. I was able to specify a system that could automatically light a pathway to and from her car to her workspace and also turn on the air conditioning to her office and set the coffee maker to brew a cup to meet her when she arrived, all based on the status of her parking structure access card as a programmer. Similar conveniences were also provided to late-working executives, building engineers, and so forth.
Information is Power when it is coupled with a really good logic cell.
Chapter Summary
1. First Generation Alarms used McCulloh Loop telegraph type alarm circuits.
2. First Generation Access Control Systems were single-door assemblies and are still available as hotel room door locks.
3. The second Generation of Access Control Systems networked eight card readers together to a dedicated computer that was about the size of a huge early electronic desk calculator.
4. The Second Generation of Alarm Systems replaced the meters and paper tapes of the first generation alarm systems with colored lamps and (at last) an audible alarm.
5. The Third Generation of Alarm/Access Control Systems began in 1968 and continued until about 1978. For the first time, Third Generation Systems combined alarm and access control into one system.
6. Up to 64 card readers and up to 256 alarm points were wired home-run style to a PDP-8 or IBM Series 1 mini-computer. These often used core memory, a Beehive Terminal, and a line printer.
7. In 1971, Intel® introduced the first 4-bit microprocessor, the 4044. This became the basis for a new kind of Alarm and Access Control System Technology called distributed controller systems. This was the beginning of Forth Generation Access Control Systems.
8. Fifth Generation Alarm and Access Control Systems are all based entirely on software-based functions (mostly SQL language) and reference databases, whereas earlier systems were based on functions that were defined in hardware.
1) Alarm/Access Control Systems are in most cases
a. Part of the Digital Video System
b. Used mostly to control visitors
c. Part of a larger integrated Security System
d. Separate systems on separate computers
2) First Generation Alarm Systems were
a. McCallan line systems
b. McCulloh Loop systems
c. McDonalds alarm systems
d. McWilliams alarm systems
3) First Generation Access Control Systems can
a. Provide access to no more than eight doors
b. Provide access only to magnetic stripe cards
c. Still be found on old buildings
d. Still be found on hotel room doors
4) Second Generation Alarm Systems
a. Replaced audio annunciators with colored lamps
b. Replaced meters and paper tape with colored lamps
c. Replaced most guards
d. Replaced most guard dogs
5) Second Generation Access Control Systems
a. Networked 8 card readers together to a computer the size of a 4-drawer filing cabinet
b. Networked 8 card readers together to a computer the size of a large early electronic calculator
c. Networked 24 card readers together along a continuous coax cable
d. Networked 24 card readers together along a common circuit at distances not to exceed 100 m
6) Third Generation Alarm/Access Control Systems
a. Wired card readers and alarms to a computer the size of a 4-drawer filing cabinet
b. Used Plug-in Dynamic Random Access Memory
c. Used dot matrix printers
d. Used color televisions as computer monitors
7) Fourth Generation Alarm/Access Control Systems
a. Used discrete transistors for processing
b. Used Nixie Tubes for displays
c. Used the first microprocessors as CPUs
d. Used highly educated guards to monitor them
8) Fourth Generation Alarm/Access Control Systems were the first to use the concept of
a. Distributed Processing
b. Distributed Card Readers
c. Distributed Consoles and Monitors
d. Distributed Power Supplies
9) By the mid-1990s, organizations wanted to integrate
a. Their employees racially
b. Their remote offices into many fewer locations
c. Alarm, Access Control, CCTV, and Intercoms into a single system
d. Alarm, Access Control, Business Computer Network, and Irrigation Systems into a single system
10) Fourth Generation Alarm/Access Control System architecture functions were defined by
a. Their logical attributes
b. Their physical attributes
c. Their programmers
d. Their operators
11) Fifth Generation Alarm/Access Control Systems are based on
a. Software-based functions (mostly SQL language)
b. Hardware-based functions (mostly EPROMs)
c. ANSI standards
d. Archimedes principle
12) In the past, several Alarm/Access Control System manufacturers used _____ to ensure good sales as organizations grew.
a. A highly trained sales force
b. A highly trained technical force
c. Highly trained monkeys
d. Planned obsolescence
13) Microcontrollers
a. Are small, single- or double-door controllers that communicate via TCP/IP
b. Are small egg-shaped elements that control most functions in the system
c. Are small battery-powered elements that control only the door lock
d. Are small battery-powered elements that communicate via RS-485
14) In the future, Microcontrollers may include
a. A video camera
b. An intercom
c. A four-port digital switch
d. An eight-port digital switch
Answers: 1) c, 2) b, 3) d, 4) b, 5) b, 6) a, 7) c, 8) a, 9) c, 10) b, 11) a, 12) d, 13) a, 14) c
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