Sosi
atawa
konci
nyaeta pakakas pikeun mukakeun naon wae nu nutup. Sosi minangka hiji hal anu poko dina kahirupan moderen jeung bisa dipanggihan di sakuliah
dunya
sarta mangrupa cara anu murah tur gampang pikeun ngamankeun rupa-rupa barang, wangunan, atawa
tutumpakan
. Manusa geus biasa mamawa sasetel sosi nu dipake sapopoena, nu biasa dihijikeun ku
gantungan konci
.
A
house key
is the most common kind of key. When held upright as if to open a door, a series of grooves on either side of the key limits the type of
lock
cylinder the key can slide into. As the key slides into the lock, a series of notches allow the
pins
to move up and down until those pins are in line with the shear line of the cylinder, allowing that cylinder to rotate freely inside the lock and the lock to open.
A
car key
or an
automobile key
is a key used to open or start an automobile, often identified with the
logo
of the car company at the head. modern key designs are usually symmetrical, and some use grooves on both sides, rather than a cut edge, to actuate the lock. It has multiple uses for the
automobile
with which it was sold. A car key can open the doors, as well as start the
ignition
, open the
glove compartment
and also open the
trunk
(boot) of the car. Some cars come with an additional key known as a
valet key
that starts the ignition and opens the drivers side door but prevents the
valet
from gaining access to valuables that are located in the trunk or the glove box. Recently, features such as
coded
immobilizers
have been implemented in newer vehicles. More sophisticated systems make ignition dependent on electronic devices, rather than the mechanical keyswitch. Ignition switches/locks are combined with security locking of the
steering column
(in many modern vehicles) or the
gear lever
(
Saab Automobile
). In the latter, the switch is between the seats, preventing damage to the driver's knee in the event of a collision.
Keyless entry systems
, which utilize a remote control in place of a car key, are becoming a standard feature on many new cars. Some of them are
handsfree
.
Some keys are high-tech in order to prevent the theft of a car.
Mercedes-Benz
uses a key that, rather than have a cut metal piece to start the car, uses an encoded
infrared
beam that communicates with the car's computer. If the codes match, the car can be started. These keys can be expensive to replace, if lost and can cost up to US$400. Some car manufacturers like
Land Rover
and
Volkswagen
use a 'switchblade' key where the key is spring-loaded out of the
fob
when a button is pressed. This eliminates the need for a separate key fob but can often make the key large and uncomfortable to keep in pockets for extended periods of time. This type of key has also been known to be confiscated by airport security officials
[1]
.
A
master key
is designed to open a set of several locks. These locks also have keys which are specific to each one (the
change key
) and cannot open any of the others in the set. Locks which have master keys have a second set of the mechanism used to open them which is identical to all of the others in the set of locks. For example, master keyed
pin tumbler locks
will have two shear points at each pin position, one for the change key and one for the master key. A far more secure (and more expensive) system has two cylinders in each lock, one for the change key and one for the master key.
Larger organizations, with more complex "grandmaster key" systems, may have several masterkey systems where the top level grandmaster key works in all of the locks in the system.
A practical attack exists to create a working master key for an entire system given only access to a single master-keyed lock and its associated key. This is described in
Cryptology and Physical Security: Rights Amplification in Master-Keyed Mechanical Locks
A
control key
is a key used in interchangeable core locking systems. The control key enables the user to remove a core in the cylinder, with a specific combination and replace it with a core with a different combination. In small format interchangeable cores, similar to those developed by
Frank Best
of the
Best Lock Corporation
, the key operates a separate shear line, located above the operating key shear line. In other format interchangeable cores, the key may work like a master key along the operating shear line and also contact a separate locking pin that holds the core in the cylinder.
A
double-sided key
is very similar to a house or car key with the exception that it has two sets of teeth, an upper level standard set of teeth and a lower, less defined set of teeth beside it. This makes the double-sided key's profile and its corresponding lock look very similar to a standard key while making the attempt to pick the lock more difficult.
A
paracentric key
is designed to open a paracentric lock. It is distinguishable by the contorted shape of its blade, which protrudes past the centre vertical line of the key barrel. Instead of the wards on the outer face of the lock simply protruding into the shape of the key along the spine, the wards protrude into the shape of the key along the entire width of the key, including along the length of the teeth.
[2]
Patented by the Yale lock company in
1898
, paracentric cylinders are not exceptionally difficult to pick, but require some skill and know-how on the part of the person attempting to pick the lock.
A
skeleton key
(or
passkey
) is a very simple design of key which usually has a cylindrical shaft (sometimes called a
shank
) and a single, minimal flat, rectangular tooth or
bit
. Skeleton keys are also usually distinguished by their
bow
, or the part one would grasp when inserting the key, which can be either very plain or extremely ornate. A skeleton key is designed to circumvent the wards in
warded locks
. Warded locks and their keys provide minimal security and only a slight deterrent as any key with a shaft and tooth that has the same or smaller dimensions will open the lock. However, warded keys were designed to only fit a matching lock and the skeleton key would often fit many. Many other objects which can fit into the lock may also be able to open it. Due to its limited usefulness, this type of lock fell out of use after more complicated types became easier to manufacture. In modern usage, it has come to describe a key, usually with minimal features, which can open all or most of a type of badly designed lock. Skeleton keys can be newly-minted (and sold by restoration hardware companies) or antiques. True skeleton keys were most popular in the late 1800s, although they continued to be used well into the 20th century and can still be found today in use, albeit in vintage homes and antique furniture. A skeleton key is distinguished from a
barrel key
in that a skeleton key usually has a solid shank, whereas a barrel shafted key can be made either by drilling out the shank from the bit end or by folding metal into a barrel shape when forging the key.
A
tubular key
(sometimes referred to as a
barrel key
when describing a vintage or antique model) is one that is designed to open a
tubular pin tumbler lock
. It has a hollow, cylindrical shaft which is usually much shorter and has a larger diameter than most conventional keys. Antique or vintage-style barrel keys often closely resemble the more traditional
skeleton key
but are a more recent innovation in keymaking. In modern keys of this type, a number of grooves of varying length are built into the outer surface at the end of the shaft. These grooves are parallel to the shaft and allow the pins in the lock to slide to the end of the groove. A small tab on the outer surface of the shaft prevents the pins in the lock from pushing the key out and works with the hollow center to guide the key as it is turned.
The modern version of this type of key is harder to duplicate as it is less common and requires a different machine from regular keys. These keys are most often seen in home alarm systems, in the United States.
Security on these types of locks are problem, as rediscovered recently. It's known as the "Bic Pen Trick."
A Zeiss key is a cross between a house key and a tubular key. It has three sets of teeth at 90 degrees to each other with a flattened fourth side. Though this type of key is easy to duplicate, the extra sets of teeth deter
lockpicking
attempts.
A
Do Not Duplicate key
is one which has been stamped
do not duplicate
by a locksmith or manufacturer as a passive deterrent to prevent a retail key cutting service from duplicating a key without authorization or without contacting the locksmith or manufacturer who originally cut the key. More importantly, this is a control system for whoever is the owner of the key, such as a maintenance person or security guard, to identify keys that should not be freely distributed or used without authorization. Though it is intended to prevent unauthorized key duplication, copying restricted keys remains a common security problem. There is no direct legal implication in the US for someone that copies a key that is stamped
do not duplicate
(unless it is a government owned key), but there are patent restrictions on some key designs (see "restricted keys").
United States Code
18 USC Sec. 1704
Archived
2011-06-07 di
Wayback Machine
deals with United States Post Office keys, and
18 USC Sec. 1386
Archived
2012-01-11 di
Wayback Machine
deals with United States Department of Defense keys.
A restricted keyblank is a keyway and blank for which a manufacturer has set up a restricted level of sales and distribution. Restricted keys are often protected by patent, which prohibits other manufacturers from making unauthorized productions of the key blank. In many jurisdictions, customers must provide proof of ID before a locksmith will duplicate a key using a restricted blank. These days, many restricted keys have special in-laid features, such as magnets, different types of metal, or even small computer chips to prevent duplication.
A
keycard
, while not actually considered a key, is a plastic card which stores a digital signature that is used with electronic
access control
locks. It is normally a flat, rectangular piece of plastic and may also serve as an
ID card
. There are several popular type of keycards in use and include the
mechanical holecard
,
bar code
,
magnetic stripe
,
smart card
(embedded with a read/write electronic
microchip
), and
RFID
proximity cards. The keycard is used by presenting it to a card reader; swiping or inserting of mag stripe cards, or in the case of
RFID
cards, merely being brought into close proximity to a sensor.
Bar code technology is not a secure form of a key, as the bar code can be copied in a photocopier and often read by the optical reader.
Magnetic stripe keycards are becoming increasingly easy to copy, but have the security advantage that one may change the stored key in a magnetic swipe card in case the current key may be compromised. This immediate change of the "key" information can be applied to other media, but this media probably offers the least expensive option, and the most convenient to users and managers of systems that use this media. Example: If you own a car with this system, you can change your keys anytime you want. You can buy new media anywhere a gift card is sold. At least at this point in time, you could buy a gift card for a penny, then use that as the media for the keys to your car. If the system uses digital environmental data samples to create the "key" string, every car can have a set of keys that no one else has. If a card is stolen, or copied without authorization, the card can be remade, and the car security system can be synchronized with the new card, and no longer activationally responsive to the copy of the old card. This approach can empower the system controller (owner/individual or centralized administration of a business).
Computerized authentication systems, such as key cards, raise
privacy
concerns, since they enable computer
surveillance
of each entry. Currently RFID cards and key fobs are becoming more and more popular due to its ease of use. Many modern households have installed
digital locks
that make use of key cards, in combination with
biometric
fingerprint
and keypad PIN options.
The first keycard was the
mechanical holecard
type patented by
Tor Sørnes
, a concept he later developed into the
magnetic stripe
card key.
History of locks and keys
[
edit
|
edit sumber
]
Wooden locks and keys were in use as early as 4,000 years ago in Egypt
[3]
.
http://www.usatoday.com/travel/flights/today/2005-06-22-sky-archivejune21_x.htm