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KEYS

Specialty Definition: KEYS

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Specialty Definition: Cryptographic key

(From Wikipedia, the free Encyclopedia)

A cryptographic key is a relatively small amount of information that is used by a cryptographic algorithm to 'customize' the transformation of plaintext into cyphertext (during encryption) or from cyphertext to plaintext (during decryption). The same algorithm and plaintext, but with a different key will produce a quite different cyphertext, and so for decryption as well. If the decryption key is lost, encrypted data will not in practice be convertible back to its original form -- at least for high quality encryption algorithms and large enough key sizes. Thus, the security of a cryptographic key in most cases relies on its being kept secret: hence the alternative name secret key.

Most cryptographic algorithms use a single key for both encryption and decryption: they are known as symmetric key algorithms. An attacker who obtains the key (by theft, extortion, dumpster diving, or inspection of a Post-It note stuck to the side of a terminal) can recover the original message from the encrypted data, since as a matter of principle the details of the cryptographic algorithm used is assumed to be already available to the attacker. This design assumption is usually known to cryptanalysts as Kerckhoffs' law -- '...only secrecy of the key provides security...', or in more colloquial form, Shannon's Maxim -- '...the enemy knows the system...'. In either form, it is fully justified by long and painful practical experience over some thousands of years and no recent development has changed this reality; indeed there is widely thought to be no prospect of change. That secrecy of a crypto system (the algorithms or the protocols) is important (or even vital) is widely, and wrongly, believed. As a general principle one would not want one's crypto system to be fully known to the opposition, but it should remain secure even if the opposition learns all about it. The chances are excellent that they will anyway.

A new class of cryptographic encryption algorithms was discovered in the 1970s which use a pair of keys, one to encrypt and one to decrypt. Some of these asymmetric key algorithms have the property that it is not possible to determine one key from the other (so far as is currently known). Such an algorithm allows one key to be made public while retaining the private key in only one location.

Key Sizes

Typical key sizes for estimated 'equivalent security' against a particular kind of attack (ie, brute force key space search) are 128 bits for symmetric ciphers and 2048 bits or more for public key cryptography. Elliptic curve cryptography may allow much smaller size keys for equivalent security, but these algorithms have only been known for a relatively short time and current estimates of the difficulty of brute force searching for their keys may not survive. Recently, a message encrypted using a 109-bit key elliptic curve algorithm was broken by brute force. As a result it would appear that elliptic curve algorithm keys must be somewhat the same length as symmetric key algorithm keys for equivalent security. As always, for all but the one-time pad, a theoretical breakthrough may make everything you've encrypted an open book regardless of the algorithm or algorithm type you've chosen, and a too-short key will certainly do so.

If the key is too small, the algorithm will be vulnerable to a brute force attack in which all possible values of the key are tried one by one. 'Birthday' attacks are also possible; the probability of a 'collision' between a large group of values goes up roughly as the square of the number of possible values and this applies in cryptography as well. In addition, many algorithms permit reduced effort attacks as compared to brute force key search. If the effort is sufficiently reduced, the algorithm will be 'insecure' against that attack and should not be used. It may be expected that algorithms for which no improved attack is now known, and for which a brute force attack is impractical, will be found to be insecure when some new cryptoanalytic technique is developed. When one is.

The problem of choosing a cryptographic algorithm reduces itself, in actual practice, to an estimate of how likely such an advance will be over the relevant time. Personal secrets need to be kept confidential for different durations than tactical deployment information in a battle, and still differently than some commercially valuable information (eg, the formula for Coke). There are no good answers known to this problem. Intelligent, cryptographically informed, choosers limit their choice to publicly known and publicly unbroken, but well studied, algorithms. Only algorithms from this group can be credibly thought secure. All others are either not sufficiently well tested, or are from secret organizations with adequate testing resources, but also with ulterior motives.

Key Choice

At the least sensible, choosing a key by increasing the value of the last used key by one is clearly foolish. Any attacker noticing the key choice pattern will be ecstatic. In fact, experience has shown that pattern in key choice are a very very significant source of breaks into otherwise well designed crypto systems. The Japanese Purple cypher machine of WWII is an example, for after the initial breakthrough by US cryptanalysts, the poor choice of keys made continuing breaks into the Purple traffic very much easier.

In general, keys _must_ be chosen randomly (or alternatively, they must be random values) while meeting other requirements of the algorithm in use. This is a fundamentally difficult, quite subtle, problem and has been 'solved' in one or another crypto system in various ways. There is an Internet RFC on generating randomness (RFC 1750, Randomness Recommendations for Security), but it is long on prescription and short on explanation. In general randomness is always a problem in cryptography, and key choice is merely another example.

Failure to handle this properly is an easy way to render any cryptosystem insecure. See randomness.

Applications

Pretty Good Privacy (PGP) is a popular program that intelligently uses both symmetric and asymmetric algorithms as part of an excellent crypto system design. PGP uses the timing between keystrokes to generate 'randomness'; thus far this has not been found unsatisfactory. A public Standard has been recently adopted for a PGP compatible crypto system. OpenPGP is the standard and GPG is an implementation of it available from the Free Software Foundation. There is a Web site for the FSF which has pointers to the official Web pages for both PGP and OpenPGP.

External links

• http://www.pobratyn.com/pk.php3 An example of a PGP Public Key. -- broken link
• The official site for PGP International and, unofficially, for GPG.
• Crypto-Gram, a monthly online publication on cryptography and its sensible use.

  Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Cryptographic key."

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Florida Keys

(From Wikipedia, the free Encyclopedia)

The Florida Keys are an archipelago of islands extending from the southeastern Florida peninsula near Miami, running south and then curving west to Key West, and out to the uninhabited Dry Tortugas. The islands lie in the Florida Straits, dividing the Atlantic Ocean to the east from the Gulf of Mexico to the west, and creating Florida Bay. At the nearest point, the southern tip of Key West is just 90 miles (145 km) from Cuba.

Key Biscayne is home to Miami Beach, and is actually attached at the north end to the mainland, therefore not considered part of the Keys by some Floridians. It is, however, part of the same geological formation, atop which sits coral rock islands, as well as partly-submerged mangrove islands. The city of Key West is the county seat of Monroe County, which covers mostly the Everglades on the mainland, and all of the islands from Key Largo south and west.

Major islands

Most of the following islands are inhabited, and connected to the Overseas Highway via local roads.

Upper keys

• Key Biscayne
• Key Largo
• Rattlesnake Key

Middle keys

• Islamorada
• Tavernier
• Plantation Key
• Matecumbe Key
• Craig Key
• Fiesta Key
• Long Key
• Conch Key
• Duck Key
• Grassy Key
• Deer Key
• Vaca Key
• Marathon Key
• Boot Key

Lower keys

• Bahia Honda
• No Name Key
• Big Pine Key
• Torch Key
• Ramrod Key
• Summerland Key
• Cudjoe Key
• Sugarloaf Key
• Saddlebunch Keys
• Big Copitt Key
• Boca Chica
• Key West

Outlying islands

These are only accessible by boat.

• the Marquesas Keys atoll
• the Dry Tortugas (not shown on map)

History

Overseas Railway

The Keys were long accessible only by water. This changed with the completion Henry Flagler's Overseas Railway in the early 1910s. Flagler, a major developer of Florida's Atlantic coast, extended his Florida East Coast Railway down to Key West with an ambitious series of over-sea railroad trestles.

Labor Day Hurricane of 1935

The Keys were the site of the deaths of hundreds of people working for the railway when Flagler refused to let his workers evacuate before the Labor Day Hurricane of 1935, which submerged the islands, destroying the railway and killing 435. Flagler County, Florida is still named after him despite this.

The storm was the most devastating to have hit the U.S. at the time, a full Category 5 with sustained winds over 155 mph (250 km/h). Only hurricanes Camille (1969) and Andrew (1992) have ever hit the U.S. with such strength since then.

Seven Mile Bridge

One of the longest bridges in existence when it was built, the Seven Mile Bridge connects Boot Key in the Middle Keys to Bahia Honda (pronounced ba-EE-uh OWN-dah in Spanish) in the Lower Keys. True to its name, it is seven miles or about 11km long, and passes over Pigeon Key, where a turnoff allows access to the small island.

After the destruction of the railway by the hurricane, it and the other bridges were rebuilt by the United States Federal Government as an automobile highway. US 1 runs the length of the Keys, and is called the Overseas Highway there. (US 1 also runs the entire way up the eastern seaboard to Maine.)

Conch Republic

In 1982, the United States Border Patrol had established a roadblock and inspection points on US Highway 1, stopping all northbound traffic returning to the mainland at Florida City, to search vehicles for illegal drugs and illegal immigrants. The Key West City Council repeatedly complained about the roadblocks, which were a major inconvenience for people traveling from Key West, and hurt the Keys' important tourism industry.

After various unsuccessful complaints and attempts to get a legal injunction against the blockade failed in federal court in Miami, on 23 April, 1982 Key West mayor Dennis Wardlow and the city council declared the independence of the Keys, calling it the "Conch Republic". After one minute of secession, he (as "President") surrendered to an officer of the Key West Naval Air Station (NAS), and requested one billion ($1,000,000,000) dollars in "foreign aid".

The stunt succeeded in generating great publicity for the Keys' plight, and the inspection station roadblock was removed.

Environment

The well-known and very sour Key lime (or Mexican lime) is a naturalized species, apparently introduced from the Yucatan Peninsula of Mexico, where it had been previously been introduced from Malaysia by explorers from Spain. The tree grows vigorously and has thorns, and produces small limes which are particularly acidic (even in highly alkaline coral sand soil) and uniquely fragrant. Naturally, Key lime pie was invented here as well.

The Keys are also home to a unique species called the Key deer, protected by the National Key Deer Refuge. About 70 miles or 110km west of Key West is Dry Tortugas National Park, one of the most isolated and therefore well-preserved in the world. The name derives from the fact that the small hump-shaped islands look like dry tortoise (tortuga in Spanish) shells from a distance.

The Keys are regularly threatened by tropical storms and hurricanes, leading to evacuations to the mainland, though locals tend to view "mandatory" as "voluntary" and "voluntary" as nothing at all. This is dangerous however, since once a storm's seriousness is realized, it is often too late for thousands of vehicles to evacuate over the two-lane causeways and low-lying islands. Hurricane Georges (pronounced zhorzh in French) was the most recent strike in 1998, hitting Key West after tearing up much of the Caribbean, before moving on to landfall in Mississippi.

Culture and recreation

The "hurricane bravado" is part of the Keys' laid-back atmosphere, as is the somewhat separatist "Conch Republic" attitude. Life is easygoing, with the major industries being tourism and fishing. Eco-tourism is also part of this, with many visitors diving in the Florida Keys National Marine Sanctuary. A new ferry now takes riders between Key West and Fort Myers, due north on the mainland, along the western edge of Florida Bay.

External links

• City of Key West
• History of the Conch Republic
• Everything about the Key lime
• More about the Marquesas
• National Park Service: Dry Tortugas
• NOAA Marine Sanctuary

  Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Florida Keys."

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Key (music)

(From Wikipedia, the free Encyclopedia)

In Music theory, the key is the tonal center of a piece. It is designated by a note name (the tonic), such as C, and can be either in major or minor mode. What a key designates to a performer is the scale in which all the diatonic notes of the piece lie. This is slightly more complicated in a minor key, because the pitch of the sixth and seventh scale degrees in a minor key can change depending on their harmonic context. The primary key of a piece of music is indicated at the beginning of the piece with a key signature.

A piece may change key at some point. This is sometimes done by just starting in the new key with no preparation - this kind of key change is common in various kinds of popular music, when a sudden change to a key a whole tone higher is a quite frequently heard device at the end of a song. In classical music, however, a "smoother" kind of key change is more usual -- this kind of key change is called modulation.

Certain musical instruments are sometimes said to play in a certain key, or have their music written in a certain key. Instruments which do not play in the key of C are known as transposing instruments. The most common kind of clarinet, for example, is said to play in the key of B flat. This means that a scale written in C major in sheet music will actually sound as a B flat major scale when played; that is, notes sound a whole tone lower than written. Likewise, the French horn, normally in the key of F, plays notes a major fifth lower than written.

Similarly, some instruments may be said to be built in a certain key. A brass instrument built in, say, B flat, will play a fundamental note of B flat, and will be able to play notes in the harmonic series starting on B flat without using valves, fingerholes, slides or otherwise altering the length of the vibrating column of air. An instrument built in a certain key will often, but not always, have its music written in the same key (see trombone for an exception).

Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Key (music)."

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Key signature

(From Wikipedia, the free Encyclopedia)

In musical notation, the key signature is the series of sharps or (alternatively) flats are to be used, unless the notes are indicated otherwise, in a section of music. Key signatures are generally written immediately after the clef at the beginning of a line of musical notation, although they can appear in other parts of a score.

Fig 1. The B-Major scale

A key signature defines the diatonic scale which a piece of music uses. Unless the piece is in the key of C, some notes must be consistently sharpened or flattened.

For example, in the key of G major, the leading-note is F sharp. The key signature indicates that each time an F is written in the staff it is in fact to be played as F sharp.

Individual sharp, flat or natural signs that modify an individual note in the piece are called accidentals (for example, an F natural in a piece in the key of G). These override the key signature for the duration of the bar they occur in.

Key signatures are in fact merely a convenience of notation. Some pieces which change key (modulate) insert a new key signature on the staff partway; while others use accidentals: natural signs to "neutralize" the key signature and other sharps or flats for the new key.

Figure 1 shows the key signature of the scale of B-major. Any note which is on the same line or space as its five sharps is increased from its natural pitch by a semitone. Although key signatures can technically consist of any collection of sharps or flats, musical tradition dictates that they be arranged in a fixed order according to the key of the piece. As each major key has an equivalent relative minor key that may be represented with the same key signature, the number of standard key signatures is less than the actual number of keys.

The table below illustrates the relative major key signatures for minor scales.

Key Sig.	Major Scale	Minor Scale
0	C major	A minor
1#	G major	E minor
2#	D major	B minor
3#	A major	F# minor
4#	E major	C# minor
5#	B major	G# minor
6#	F# major	D# minor
7#	C# major	A# minor
1b	F major	D minor
2b	Bb major	G minor
3b	Eb major	C minor
4b	Ab major	F minor
5b	Db major	Bb minor
6b	Gb major	Eb minor
7b	Cb major	Ab minor

For key signatures with sharps, the first sharp is placed on F line (for the key of G major/E minor). Subsequent additional sharps are added on C, G, D, A, E and B. For key signatures with flats, the first flat is placed on the B line, with subsequent flats on E, A, D, G, C and F. There are 15 different key signatures, including the "empty" signature of C major/A minor.

The key signatures with seven flats and seven sharps are very rarely used, because they have simpler enharmonic equivalents. For example, the key of C# major (seven sharps) is more simply represented as Db major (five flats) - for modern practical purposes these keys are the same, because C# and Db are the same note. Pieces are written in these seven sharp or flat keys, however. The third Prelude and Fugue from Book One of Johann Sebastian Bach's Well-Tempered Clavier is in C# major, for example.

In cryptography, a key signature is the result of applying a hash function on a key, for the purpose of simplifying operations on keys. For example, cryptographic keys are often quite large and cumbersome to compare, so a user who wants to verify the presence of a public key in a database might use a smaller key signature rather than comparing the whole key.

Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Key signature."

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Keys, Oklahoma

(From Wikipedia, the free Encyclopedia)

Keys is a town located in Cherokee County, Oklahoma. As of the 2000 census, the town had a total population of 458.

Geography

Keys is located at 35°48'19" North, 94°56'46" West (35.805324, -94.946071)¹. According to the United States Census Bureau, the town has a total area of 14.2 km² (5.5 mi²). 14.2 km² (5.5 mi²) of it is land and none of the area is covered with water.

Demographics

As of the census of 2000, there are 458 people, 174 households, and 128 families residing in the town. The population density is 32.2/km² (83.3/mi²). There are 194 housing units at an average density of 13.6/km² (35.3/mi²). The racial makeup of the town is 56.77% White, 0.00% African American, 32.10% Native American, 0.00% Asian, 0.00% Pacific Islander, 0.66% from other races, and 10.48% from two or more races. 3.06% of the population are Hispanic or Latino of any race. There are 174 households out of which 37.4% have children under the age of 18 living with them, 57.5% are married couples living together, 13.8% have a female householder with no husband present, and 26.4% are non-families. 20.1% of all households are made up of individuals and 7.5% have someone living alone who is 65 years of age or older. The average household size is 2.63 and the average family size is 3.03. In the town the population is spread out with 28.4% under the age of 18, 9.4% from 18 to 24, 27.9% from 25 to 44, 23.8% from 45 to 64, and 10.5% who are 65 years of age or older. The median age is 34 years. For every 100 females there are 100.0 males. For every 100 females age 18 and over, there are 98.8 males. The median income for a household in the town is $16,691, and the median income for a family is $17,279. Males have a median income of $29,000 versus $23,500 for females. The per capita income for the town is $11,650. 33.9% of the population and 33.7% of families are below the poverty line. Out of the total people living in poverty, 47.1% are under the age of 18 and 31.7% are 65 or older.

Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Keys, Oklahoma."

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Locksmithing

(From Wikipedia, the free Encyclopedia)

Locksmithing is the science and art of making and defeating locks. A lock is a mechanism that secures buildings, rooms, cabinets, or other storage facilities from theft by burglars. A key is usually used to open a lock. It is often said that "a lock keeps honest people honest."

Practitioners are called locksmiths. Locksmithing is one of the earliest forms of security engineering. Lock-picking was one of the first methods of cracking security systems.

The issue of full disclosure was first raised in the context of locksmithing.

Topics in locksmithing

• Mortice lock
• Warded lock
• Cylinder lock
• Combination lock
• Lock-picking
• Lock-bypassing
• Pin tumbler lock
• Tubular pin tumbler lock
• Disc tumbler lock

External links

• The alt.locksmithing FAQ
• MIT guide to lock-picking by 'Ted the Tool'

Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Locksmithing."

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Modern Usage: KEYS

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Commercial Usage: KEYS

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Image Slideshow: KEYS

Photos: KEYS More pictures...

Illustrations: KEYS More pictures...

Computer Images: KEYS More pictures...

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Photo Album: KEYS

Thumbnail	Description & Credit	Thumbnail	Description & Credit
	"Living in a Box" by Rainer Wonisch. Use the arrow keys to rotate the box to see what's inside.		"Paddlewheel" by Hassan Sedaghat. Use the arrow keys to spin it.
	C&GS Ship HYDROGRAPHER as seen from photogrammetric aircraft First photo mission for C&GS was an attempt to determined depths in clear water Project in Florida Keys - ship was used as fixed reference program Cooperative project with Aeroplane Service of the Navy. Credit: Coast & Geodetic Survey Historical Image Collection.		Tide staff installation at Florida Keys site Tides party of Gerald B. Mills. Credit: Coast & Geodetic Survey Historical Image Collection.
	Stone crab pots and fishing boats work out of small inlets in the Florida Keys. Credit: Fisheries.		The MV Columbus Iselin grounded on Looe Key in the Florida Keys National Marine Sanctuary in August 1994. When the ship grounded it caused extensive damage to the reef. This image shows a huge swath of coral rubble at the impact site. Credit: NOAA Restoration Center.
	Jobos Bay National Estuarine Research Reserve. Fifteen small islets are part of the Caribe Keys, where the seagrass, coral reef , and mangrove habitats intersect and interconnect. Credit: National Estuarine Research Reserve System (NERR).		Endangered sea turtle cruises a coral reef in the Florida Keys. Credit: National Undersea Research Program (NURP).
	Spotted eagle ray soars over Florida Keys reefs. Aetobatus sp. Credit: National Undersea Research Program (NURP).		Queen angelfish at the reef. 1987 Florida Keys National Marine Sanctuary Photo Contest entry. Credit: The Coral Kingdom.
Source: pictures compiled by the editor from various references; see picture credits.

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Digital Photo Gallery: KEYS
 

"More keys" by Jennifer Lin Commentary: "Clearer picture of keyboard keys."	"Keys" by Truth Noize Commentary: "Keys on a table."
Source: photographs selected by the editor, with permission from the photographers.

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Sounds Captioned with "KEYS".

Play	Caption	Play	Caption
	Ascending piano pattern modulating through different keys with strings.		Keys clanking together; wooden chair sliding against a linoleum floor.
Source: compiled by the editor from various references; see credits.

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Familiar Quotations: KEYS

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Non-Fiction Usage: KEYS

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Usage Frequency: KEYS

Source: compiled by the editor from several corpora; see credits.

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Name Usage Frequency: KEYS

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Expression: KEYS

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Frequency of Internet Keywords: KEYS

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Modern Translation: KEYS

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Bible Trace: KEYS

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Derivations & Misspellings: KEYS

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Rhyming with "KEYS"

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