Sensor selection (PIR, glass-break, contacts) in New Britain, Connecticut isn't just a tech checklist, it's a house-by-house decision that lives in real weather, old walls, busy streets, and the way folks actually move around their homes. If you've lived here a winter or two, you know: the cold sneaks in through basement doors, radiators and baseboards kick heat at odd times, and old sash windows don't always sit square. All of that matters when you're deciding what sensors to trust and where to put them.
Start with PIR motion sensors (passive infrared). They look for changes in heat moving across their field of view. In New Britain's mix of capes, three-deckers, and post-war ranches, PIRs work great in central areas-hallways, family rooms, and the bottom of stairs-where a person would naturally pass. But there's caveats. If you've got steam radiators or sun that punches through in the late afternoon, a poorly aimed PIR can false. Don't mount one facing a window where the winter sun rides low and bounces off snow, and try not to put it directly over a heater. High-traffic pets complicate things too. You can get “pet immune” models, but they aren't magic; a big dog jumping onto a couch basically becomes a person to the sensor. And those lovely plaster-and-lath walls in older houses can reflect or constrain coverage oddly, so test the walk path after you stick one up (seriously, just walk around and watch the panel).
Glass-break detectors come in two flavors: acoustic (listening) and shock (vibration on the frame). For most homes near downtown or along busier roads, I lean acoustic inside rooms with broad window exposure. But if you've got thick drapes or storm windows, sound gets muffled, so a shock sensor on the sash may be smarter. Double-pane vinyl replacements behave differently than original wood; laminated panes-less common in older homes, more in new builds-don't shatter the same way, which can confuse some acoustic models. Kitchens can be noisy, and clattering dishes or a dropped pot could trick a cheap mic, so keep a little distance there. In small rooms, an acoustic unit can cover multiple windows as long as line-of-sight isn't blocked by bookcases or a deep soffit. Before you mount anything, clap and talk in the room to get a feel for how sound carries (it's low-tech, but it works).
Door and window contacts are the foundation. They're quiet until something opens. For New Britain basements with old bulkhead doors, dampness is the enemy; choose sealed contacts, and don't trust flimsy adhesive when it's cold-screw them in. On metal doors, use spacers so the magnet doesn't stick to the slab itself. For double-hung windows, a sash contact near the top rail lets you know if somebody tries to flip the lock and slide. If you do partial ventilation in spring, consider a second magnet so the panel knows when a window is “open but allowed.” Contacts are humble, cheap, and reliable, and they don't care about pets or sunlight, which is why I still start here for perimeters.
Wireless versus wired is another New Britain-specific call. Older multi-family buildings with thick plaster, wire mesh, and brick cut wireless range fast. If you can run wire during a renovation, do it (future you will thank you). If not, pick sensors with proven range at the right frequency and supervision intervals that won't drain batteries too fast. Cold mudrooms or unheated porches drag battery life down; don't be surprised if those cells need replacement sooner. And while most adhesives do fine in summer, they lift when it's 15 degrees and damp, so mechanical mounting beats tape in those spots.
False alarms aren't just a nuisance; they can cost you. The city may require alarm registration and assesses fees after repeated false dispatches, and your neighbors won't exactly love it either. Good selection helps. A contact on a basement door beats a PIR in a cluttered basement where a hanging tarp flutters when the dryer kicks on. An acoustic glass-break in a living room with big sliders is smart, but not if the sensor is pointed past heavy velvet curtains that swallow sound. Pick the right mix, and your system actually stays quiet when it should!
Here's a quick way to think through a typical New Britain home:
A few practical habits go a long way. Don't mount sensors right after bringing them in from a cold car; condensation can mess with electronics. Don't place a PIR where a ceiling fan or HVAC supply blows directly. And don't assume your Wi‑Fi map equals your sensor radio map-they're not the same band, not the same physics. Do a walk test, arm in stay mode one evening, and quietly move around to see what trips. You'll learn more in ten minutes than from any spec sheet.
Finally, it's worth leaning on a local pro when needed. New Britain's housing stock is quirky, and a licensed low‑voltage installer has probably seen your exact window problem already. But even if you're DIY, thoughtful selection (PIR for movement, glass-break for panes, contacts for openings), smart placement, and a bit of testing will give you a system that works when it must and rests when it can. Oh, and keep spare batteries in a dry drawer-winter doesn't care about your schedule.
In telecommunications, structured cabling is building or campus cabling infrastructure that consists of a number of standardized smaller elements (hence structured) called subsystems. Structured cabling components include twisted pair and optical cabling, patch panels and patch cables.
Structured cabling is the design and installation of a cabling system that will support multiple hardware uses and be suitable for today's needs and those of the future. With a correctly installed system, current and future requirements can be met, and hardware that is added in the future will be supported.[1]
Structured cabling design and installation is governed by a set of standards that specify wiring data centers, offices, and apartment buildings for data or voice communications using various kinds of cable, most commonly Category 5e (Cat 5e), Category 6 (Cat 6), and fiber-optic cabling and modular connectors. These standards define how to lay the cabling in various topologies in order to meet the needs of the customer, typically using a central patch panel (which is often mounted in a 19-inch rack), from where each modular connection can be used as needed. Each outlet is then patched into a network switch (normally also rack-mounted) for network use or into an IP or PBX (private branch exchange) telephone system patch panel.
Lines patched as data ports into a network switch require simple straight-through patch cables at each end to connect a computer. Voice patches to PBXs in most countries require an adapter at the remote end to translate the configuration on 8P8C modular connectors into the local standard telephone wall socket. In North America no adapter is needed for certain uses: With ports wired in the preferred standard T568A pattern, for the 6P2C plugs most commonly used for single-line phone equipment (e.g. with RJ11), and 6P4C plugs used for two-line phones without power (e.g. with RJ14) and single-line phones with power (again RJ11), telephone connections are physically and electrically compatible with the larger 8P8C socket, but with ports wired as T568B, which is common but often in violation of the standard, only the first pair, i.e. line 1, works.[a] RJ25 and RJ61 connections are physically but not electrically compatible, and cannot be used. In the United Kingdom, an adapter must be present at the remote end as the 6-pin BT socket is physically incompatible with 8P8C.
It is common to color-code patch panel cables to identify the type of connection, though structured cabling standards do not require it except in the demarcation wall field.[specify]
Cabling standards require that all eight conductors in Cat 5e/6/6A cable be connected.
IP phone systems can run the telephone and the computer on the same wires, eliminating the need for separate phone wiring.
Regardless of copper cable type (Cat 5e/6/6A), the maximum distance is 90 m for the permanent link installation, plus an allowance for a combined 10 m of patch cords at the ends.
Cat 5e and Cat 6 can both effectively run power over Ethernet (PoE) applications up to 90 m. However, due to greater power dissipation in Cat 5e cable, performance and power efficiency are higher when Cat 6A cabling is used to power and connect to PoE devices.[1]
Structured cabling consists of six subsystems:[2]
Network cabling standards are used internationally and are published by ISO/IEC, CENELEC and the Telecommunications Industry Association (TIA). Most European countries use CENELEC, International Electrotechnical Commission (IEC) or International Organization for Standardization (ISO) standards. The main CENELEC document is EN50173, which introduces contextual links to the full suite of CENELEC documents. ISO/IEC 11801 heads the ISO/IEC documentation.[3] In the US, the Telecommunications Industry Association issue the ANSI/TIA-568 standards for telecommunications cabling in commercial premises.
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In physical security and information security, access control (AC) is the action of deciding whether a subject should be granted or denied access to an object (for example, a place or a resource). The act of accessing may mean consuming, entering, or using. It is often used interchangeably with authorization, although the authorization may be granted well in advance of the access control decision.[1]
Access control on digital platforms is also termed admission control. The protection of external databases is essential to preserve digital security.[2]
Access control is considered to be a significant aspect of privacy that should be further studied. Access control policy (also access policy) is part of an organization’s security policy. In order to verify the access control policy, organizations use an access control model.[3] General security policies require designing or selecting appropriate security controls to satisfy an organization's risk appetite - access policies similarly require the organization to design or select access controls.
Broken access control is often listed as the number one risk in web applications.[4] On the basis of the "principle of least privilege", consumers should only be authorized to access whatever they need to do their jobs, and nothing more.[5]
Geographical access control may be enforced by personnel (e.g. border guard, bouncer, ticket checker), or with a device such as a turnstile. There may be fences to avoid circumventing this access control. An alternative of access control in the strict sense (physically controlling access itself) is a system of checking authorized presence, see e.g. Ticket controller (transportation). A variant is exit control, e.g. of a shop (checkout) or a country.[6]
The term access control refers to the practice of restricting entrance to a property, a building, or a room to authorized persons. Physical access control can be achieved by a human (a guard, bouncer, or receptionist), through mechanical means such as locks and keys, or through technological means such as access control systems like the mantrap. Within these environments, physical key management may also be employed as a means of further managing and monitoring access to mechanically keyed areas or access to certain small assets.[6]
Physical access control is a matter of who, where, and when. An access control system determines who is allowed to enter or exit, where they are allowed to exit or enter, and when they are allowed to enter or exit. Historically, this was partially accomplished through keys and locks. When a door is locked, only someone with a key can enter through the door, depending on how the lock is configured. Mechanical locks and keys do not allow restriction of the key holder to specific times or dates. Mechanical locks and keys do not provide records of the key used on any specific door, and the keys can be easily copied or transferred to an unauthorized person. When a mechanical key is lost or the key holder is no longer authorized to use the protected area, the locks must be re-keyed.[7]
Electronic access control (EAC) uses computers to solve the limitations of mechanical locks and keys. It is particularly difficult to guarantee identification (a critical component of authentication) with mechanical locks and keys. A wide range of credentials can be used to replace mechanical keys, allowing for complete authentication, authorization, and accounting. The electronic access control system grants access based on the credential presented. When access is granted, the resource is unlocked for a predetermined time and the transaction is recorded. When access is refused, the resource remains locked and the attempted access is recorded. The system will also monitor the resource and alarm if the resource is forcefully unlocked or held open too long after being unlocked.[6]
When a credential is presented to a reader, the reader sends the credential's information, usually a number, to a control panel, a highly reliable processor. The control panel compares the credential's number to an access control list, grants or denies the presented request, and sends a transaction log to a database. When access is denied based on the access control list, the door remains locked. If there is a match between the credential and the access control list, the control panel operates a relay that in turn unlocks the resource. The control panel also ignores an opening signal to prevent an alarm. Often the reader provides feedback, such as a flashing red LED for an access denied and a flashing green LED for an access granted.[8]
The above description illustrates a single factor transaction. Credentials can be passed around, thus subverting the access control list. For example, Alice has access rights to the server room, but Bob does not. Alice either gives Bob her credential, or Bob takes it; he now has access to the server room. To prevent this, two-factor authentication can be used. In a two factor transaction, the presented credential and a second factor are needed for access to be granted; another factor can be a PIN, a second credential, operator intervention, or a biometric input.[8]
There are three types (factors) of authenticating information:[9]
Passwords are a common means of verifying a user's identity before access is given to information systems. In addition, a fourth factor of authentication is now recognized: someone you know, whereby another person who knows you can provide a human element of authentication in situations where systems have been set up to allow for such scenarios. For example, a user may have their password, but have forgotten their smart card. In such a scenario, if the user is known to designated cohorts, the cohorts may provide their smart card and password, in combination with the extant factor of the user in question, and thus provide two factors for the user with the missing credential, giving three factors overall to allow access.[citation needed]
A credential is a physical/tangible object, a piece of knowledge, or a facet of a person's physical being that enables an individual access to a given physical facility or computer-based information system. Typically, credentials can be something a person knows (such as a number or PIN), something they have (such as an access badge), something they are (such as a biometric feature), something they do (measurable behavioural patterns), or some combination of these items. This is known as multi-factor authentication. The typical credential is an access card or key-fob, and newer software can also turn users' smartphones into access devices.[10]
There are many card technologies including magnetic stripe, bar code, Wiegand, 125 kHz proximity, 26-bit card-swipe, contact smart cards, and contactless smart cards. Also available are key-fobs, which are more compact than ID cards, and attach to a key ring. Biometric technologies include fingerprint, facial recognition, iris recognition, retinal scan, voice, and hand geometry. The built-in biometric technologies found on newer smartphones can also be used as credentials in conjunction with access software running on mobile devices.[11] In addition to older more traditional card access technologies, newer technologies such as near-field communication (NFC), Bluetooth low energy or Ultra-wideband (UWB) can also communicate user credentials to readers for system or building access.[12][13][14]
Components of an access control system include:
Access control decisions are made by comparing the credentials to an access control list. This look-up can be done by a host or server, by an access control panel, or by a reader. The development of access control systems has observed a steady push of the look-up out from a central host to the edge of the system, or the reader. The predominant topology circa 2009 is hub and spoke with a control panel as the hub, and the readers as the spokes. The look-up and control functions are by the control panel. The spokes communicate through a serial connection; usually RS-485. Some manufactures are pushing the decision making to the edge by placing a controller at the door. The controllers are IP enabled, and connect to a host and database using standard networks[16]
Access control readers may be classified by the functions they are able to perform:[17]
Some readers may have additional features such as an LCD and function buttons for data collection purposes (i.e. clock-in/clock-out events for attendance reports), camera/speaker/microphone for intercom, and smart card read/write support.
1. Serial controllers. Controllers are connected to a host PC via a serial RS-485 communication line (or via 20mA current loop in some older systems). External RS-232/485 converters or internal RS-485 cards have to be installed, as standard PCs do not have RS-485 communication ports.[citation needed]
Advantages:[citation needed]
Disadvantages:[citation needed]
2. Serial main and sub-controllers. All door hardware is connected to sub-controllers (a.k.a. door controllers or door interfaces). Sub-controllers usually do not make access decisions, and instead forward all requests to the main controllers. Main controllers usually support from 16 to 32 sub-controllers.
3. Serial main controllers & intelligent readers. All door hardware is connected directly to intelligent or semi-intelligent readers. Readers usually do not make access decisions, and forward all requests to the main controller. Only if the connection to the main controller is unavailable, will the readers use their internal database to make access decisions and record events. Semi-intelligent reader that have no database and cannot function without the main controller should be used only in areas that do not require high security. Main controllers usually support from 16 to 64 readers. All advantages and disadvantages are the same as the ones listed in the second paragraph.
4. Serial controllers with terminal servers. In spite of the rapid development and increasing use of computer networks, access control manufacturers remained conservative, and did not rush to introduce network-enabled products. When pressed for solutions with network connectivity, many chose the option requiring less efforts: addition of a terminal server, a device that converts serial data for transmission via LAN or WAN.
All the RS-485-related advantages and disadvantages also apply.
5. Network-enabled main controllers. The topology is nearly the same as described in the second and third paragraphs. The same advantages and disadvantages apply, but the on-board network interface offers a couple of valuable improvements. Transmission of configuration and user data to the main controllers is faster, and may be done in parallel. This makes the system more responsive, and does not interrupt normal operations. No special hardware is required in order to achieve redundant host PC setup: in the case that the primary host PC fails, the secondary host PC may start polling network controllers. The disadvantages introduced by terminal servers (listed in the fourth paragraph) are also eliminated.
6. IP controllers. Controllers are connected to a host PC via Ethernet LAN or WAN.
7. IP readers. Readers are connected to a host PC via Ethernet LAN or WAN.
The advantages and disadvantages of IP controllers apply to the IP readers as well.
The most common security risk of intrusion through an access control system is by simply following a legitimate user through a door, and this is referred to as tailgating. Often the legitimate user will hold the door for the intruder. This risk can be minimized through security awareness training of the user population or more active means such as turnstiles. In very high-security applications this risk is minimized by using a sally port, sometimes called a security vestibule or mantrap, where operator intervention is required presumably to assure valid identification.[18]
The second most common risk is from levering a door open. This is relatively difficult on properly secured doors with strikes or high holding force magnetic locks. Fully implemented access control systems include forced door monitoring alarms. These vary in effectiveness, usually failing from high false positive alarms, poor database configuration, or lack of active intrusion monitoring. Most newer access control systems incorporate some type of door prop alarm to inform system administrators of a door left open longer than a specified length of time.[19][20][21]
The third most common security risk is natural disasters. In order to mitigate risk from natural disasters, the structure of the building, down to the quality of the network and computer equipment vital. From an organizational perspective, the leadership will need to adopt and implement an All Hazards Plan, or Incident Response Plan. The highlights of any incident plan determined by the National Incident Management System must include Pre-incident planning, during incident actions, disaster recovery, and after-action review.[22]
Similar to levering is crashing through cheap partition walls. In shared tenant spaces, the divisional wall is a vulnerability. A vulnerability along the same lines is the breaking of sidelights.[citation needed]
Spoofing locking hardware is fairly simple and more elegant than levering. A strong magnet can operate the solenoid controlling bolts in electric locking hardware. Motor locks, more prevalent in Europe than in the US, are also susceptible to this attack using a doughnut-shaped magnet. It is also possible to manipulate the power to the lock either by removing or adding current, although most Access Control systems incorporate battery back-up systems and the locks are almost always located on the secure side of the door. [citation needed]
Access cards themselves have proven vulnerable to sophisticated attacks. Enterprising hackers have built portable readers that capture the card number from a user's proximity card. The hacker simply walks by the user, reads the card, and then presents the number to a reader securing the door. This is possible because card numbers are sent in the clear, no encryption being used. To counter this, dual authentication methods, such as a card plus a PIN should always be used.
Many access control credentials unique serial numbers are programmed in sequential order during manufacturing. Known as a sequential attack, if an intruder has a credential once used in the system they can simply increment or decrement the serial number until they find a credential that is currently authorized in the system. Ordering credentials with random unique serial numbers is recommended to counter this threat.[23]
Finally, most electric locking hardware still has mechanical keys as a fail-over. Mechanical key locks are vulnerable to bumping.[24]
In computer security, general access control includes authentication, authorization, and audit. A more narrow definition of access control would cover only access approval, whereby the system makes a decision to grant or reject an access request from an already authenticated subject, based on what the subject is authorized to access. Authentication and access control are often combined into a single operation, so that access is approved based on successful authentication, or based on an anonymous access token. Authentication methods and tokens include passwords, biometric analysis, physical keys, electronic keys and devices, hidden paths, social barriers, and monitoring by humans and automated systems.
In any access-control model, the entities that can perform actions on the system are called subjects, and the entities representing resources to which access may need to be controlled are called objects (see also Access Control Matrix). Subjects and objects should both be considered as software entities, rather than as human users: any human users can only have an effect on the system via the software entities that they control.[citation needed]
Although some systems equate subjects with user IDs, so that all processes started by a user by default have the same authority, this level of control is not fine-grained enough to satisfy the principle of least privilege, and arguably is responsible for the prevalence of malware in such systems (see computer insecurity).[citation needed]
In some models, for example the object-capability model, any software entity can potentially act as both subject and object.[citation needed]
As of 2014[update], access-control models tend to fall into one of two classes: those based on capabilities and those based on access control lists (ACLs).
Both capability-based and ACL-based models have mechanisms to allow access rights to be granted to all members of a group of subjects (often the group is itself modeled as a subject).[citation needed]
Access control systems provide the essential services of authorization, identification and authentication (I&A), access approval, and accountability where:[25]
Access to accounts can be enforced through many types of controls.[26]
In telecommunications, the term access control is defined in U.S. Federal Standard 1037C[34] with the following meanings:
This definition depends on several other technical terms from Federal Standard 1037C.
Special public member methods – accessors (aka getters) and mutator methods (often called setters) are used to control changes to class variables in order to prevent unauthorized access and data corruption.
In public policy, access control to restrict access to systems ("authorization") or to track or monitor behavior within systems ("accountability") is an implementation feature of using trusted systems for security or social control.
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