Semicolon: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Vieque
m Disambiguate Colon to Colon (punctuation) using popups
Line 1: Line 1:
{{Redirect|ElGamal|signature algorithm|ElGamal signature scheme}}
Many men are clueless about what their wives actually need in terms of the materialistic. From final-minute frantic online procuring, to operating via malls in a daze, one can get tangled in a web of confusion in terms of looking for the idyllic gift.<br><br>Tire width refers to how broad or how slim is the tire. Having a wider tire will give the car a greater grip on dry pavement; nonetheless, the gas mileage will do worse. Additionally, an excessive amount of width may trigger injury attributable to tires chafing in opposition to the automobile's body. Slender tires have good traction throughout winter; but too narrow can put your safety at greater threat. There should always be sufficient rubber touching the highway for the automotive to maintain going. are making a name for themselves and getting wonderful reviews, so attempt a set at the moment; Grapplers can be found in a huge variety of sizes so you can you should definitely discover some to suit your wheels. Nitto Off Street Tires Nitto Mud Grappler Uneven wear of your tires is likely to be an indication of poor wheel positioning. Learn how to Seal Tire Rims With Ether<br><br>Buy entrance wheel drive chrome rims or rear wheel drive truck rims, the products we sell embrace hundreds of chrome wheels to select from. We promote the good kinds in car rims and in addition truck rims. You will save tons of on our prices whenever you purchase automotive wheels and low-cost tires prices in comparison with our opponents. We additionally sell 24 inch rims with superior spinners and truck rims with that deep chrome luster. Whether you need to buy 20 inch customized wheels or 22 inch truck rims, our costs are the lowest around. We promote one low price to your door on all of our automobile rims and custom wheels. In case you are trying to buy chrome rims or truck rims, you will not find a lower price wherever.<br><br>When on the lookout for a trailer for sale, keep in mind to search for some very important details. First, a trailer puts additional weight on the automobile, so search for a trailer that is meant for the automobile kind you can be utilizing. After deciding what size of trailer your automobile can haul, there are just a few different issues you must look for. Begin by checking the ware and tear of the tires if they are not new. Then verify for proper tire stress. The hitch and safety chains needs to be effectively inspected to ensure they connect properly. The brakes also should be seemed over for good working situation.<br><br>When choosing used tires, you do not know for sure about the history of its usage, whether or not they have been on a car involved in an accident and how had the earlier driver used the tires. Since crap tires have change into an environmental concern because they're illegally dumped in landfills, it is wiser to give them for reuse to your local recycling plant. Fear god, respect humanity and by no means resell your used tires. Chances are you'll be saving a couple of bucks on used tires, however chances are you'll be putting the lives of your passengers and yourself at a huge risk!<br><br>Aug 14 FULL AC 35W HIDs Package Particular Sale - Local Store $sixty five (san jose downtown) pic map auto elements - by seller Look at the tires for any signs of wear and tear and tear. Also, test if the tires match in size and model. This article throws gentle on the benefits concerned with purchasing a franchise enterprise for sale and it speaks about the most effective methodology of method to establish the best enterprise opportunity. How one can Properly Rotate Automobile Tires How A lot Air to Put in Tires With a Payload? Quality tires are a key component of driving security regardless of what model Toyota you drive. There are numerous tires from which to choose, together with these recommended by the manufacturer.  If you cherished this article and you simply would like to obtain more info regarding [http://ow.ly/AhDNp purchase tires] generously visit our own website. How one can Redeem Your Sears Rebate On-line Specifications for Goodyear Integrity Tires Learn how to Buy Goodyear Fortera Tires<br><br>Once you reside in a spot like Denver where you is perhaps sure to see snow within the winter, chances are high you will want to opt for the crossover or all-terrain kind best place to buy tires , which could be a bit extra aggressive tread pattern enabling you to have a better grip on snowy streets and journey the back nation mountain roads a bit more securely. Winter Mud & Snow tires fall primarily into the all-terrain category of tire dimension calculator I am betting that extra people inside the jap United States are wishing they'd a greater all-terrain tire this 12 months with the heavy snow that has pummeled them this winter.<br><br>Aug 14 AEM Adjustable Camgears & Cams for '97 Prelude $220 (fremont / union city / newark) pic auto elements - by owner Aug 14 Rial 15 Inch wheels $300 (vallejo / benicia) pic auto components - by owner Aug 14 █ One 18" 245/forty/18 Dunlop SP Sport 01 DSST Run Flat Tire, BMW █ $60 (san mateo) pic auto parts - by owner Aug 14 Ford Mustang T-5 Bell Housing (Put in Once) $a hundred and fifty (san mateo) pic auto components - by proprietor Aug 14 AE86 Corolla Gts Sr5 Supra Celica Wheels $1 pic map auto elements - by proprietor 8000 Aug 14 Porsche 1987 911 chassis $8000 (harmony / pleasant hill / martinez) pic map auto parts - by owner Aug 14 67Olds Cutlass Electric window right door 2door Hardtop, Conv., exc. $400 (twin peaks / diamond hts) auto parts - by owner OBTAINED METRIC TIRES? Divide your metric tire<br><br>With the US economy the way in which it is and Sears D+ stability sheet proper now, I do not see any upside there and all draw back in the intervening time, particularly if the broad market sells off which I think is coming again very quickly. The retailing enterprise is all the time a tough enterprise mannequin to be in and with the compounded financial problems for the US client sector, the US retail trade is going to have a tricky time earning profits for shareholders for the foreseeable future in my view.<br><br>days ago Mavis Low cost Tire, Fishkill days in the past Mavis Low cost Tire, Greenwich days ago Mavis Low cost Tire, Franklin Square (Hemp tpk) days ago Mavis Discount Tire, Pleasantville Solely 2000 miles however these tires far exceeded my expectations. They are quiet, they handle very effectively and I am very blissful. They are wider than the stock 20 inch tires and shorter however handle significantly better than the originals. The 255/50's are cheaper then the stick measurement but feel so significantly better." - YORKTOWN HEIGHTS, NY days in the past Mavis Low cost Tire, Massapequa Park days ago Mavis Low cost Tire, Franklin Sq. (Franklin ave) days in the past Mavis Low cost Tire, Cicero So far so good. Glorious tires for the price. A really satisfied buyer." - YONKERS, NY days in the past Mavis Low cost Tire, Webster Tire wear and Getting older
 
In [[cryptography]], the '''ElGamal encryption system''' is an [[asymmetric key encryption algorithm]] for [[public-key cryptography]] which is based on the [[Diffie–Hellman key exchange]]. It was described by [[Taher Elgamal]] in 1984.<ref>{{cite journal |author=Taher ElGamal |title=A Public-Key Cryptosystem and a Signature Scheme Based on Discrete Logarithms |journal=IEEE Transactions on Information Theory |volume=31 |issue=4 |year=1985 |pages=469–472 |doi=10.1109/TIT.1985.1057074 |url=http://caislab.kaist.ac.kr/lecture/2010/spring/cs548/basic/B02.pdf}} (conference version appeared in [[CRYPTO]]'84, pp. 10&ndash;18)</ref> ElGamal encryption is used in the free [[GNU Privacy Guard]] software, recent versions of [[Pretty Good Privacy|PGP]], and other [[cryptosystem]]s.  The [[Digital Signature Algorithm]] is a variant of the [[ElGamal signature scheme]], which should not be confused with ElGamal encryption.
 
ElGamal encryption can be defined over any [[cyclic group]] <math>G</math>. Its security depends upon the difficulty of a certain problem in <math>G</math> related to computing [[discrete logarithm]]s (see below).
 
== The algorithm ==
ElGamal encryption consists of three components: the key generator, the encryption algorithm, and the decryption algorithm.
 
=== Key generation ===
The key generator works as follows:
 
* Alice generates an efficient description of a multiplicative cyclic group <math>G\,</math> of order <math>q\,</math> with [[generating set of a group|generator]] <math>g\,</math>. See below for a discussion on the required properties of this group.
* Alice chooses a random <math>x\,</math> from <math>\{1, \ldots, q-1\}</math>.
* Alice computes <math>h = g^x\,</math>.
* Alice publishes <math>h\,</math>, along with the description of <math>G, q, g\,</math>, as her '''[[public key]]'''. Alice retains <math>x\,</math> as her '''private key''' which must be kept secret.
 
=== Encryption ===
The encryption algorithm works as follows: to encrypt a message <math>m\,</math> to Alice under her public key <math>(G,q,g,h)\,</math>,
 
* Bob chooses a random <math>y\,</math> from <math>\{1, \ldots, q-1\}</math>, then calculates <math>c_1=g^y\,</math>.
* Bob calculates the shared secret <math>s=h^y\,</math>.  
 
* Bob converts his secret message <math>m\,</math> into an element <math>m'\,</math> of <math>G\,</math>.
* Bob calculates <math>c_2=m'\cdot s</math>.
* Bob sends the ciphertext <math>(c_1,c_2)=(g^y, m'\cdot h^y)=(g^y, m'\cdot(g^x)^y)\,</math> to Alice.
 
Note that one can easily find <math>h^y\,</math> if one knows <math>m'\,</math>. Therefore, a new <math>y\,</math> is generated for every message to improve security. For this reason, <math>y\,</math> is also called an [[ephemeral key]].
 
=== Decryption ===
The decryption algorithm works as follows: to decrypt a ciphertext <math>(c_1,c_2)\,</math> with her private key <math>x\,</math>,
* Alice calculates the shared secret <math>s=c_1^x\,</math>
* and then computes <math>m'=c_2 \cdot s^{-1}\,</math> which she then converts back into the plaintext message <math>m\,</math>, where <math>s^{-1}</math> is the inverse of <math>s</math> in the group <math>G</math>. (E.g. [[modular multiplicative inverse]] if <math>G</math> is a subgroup of a [[multiplicative group of integers modulo n]]).
 
The decryption algorithm produces the intended message, since
 
:<math> c_2 \cdot s^{-1} = m'\cdot h^y \cdot (g^{xy})^{-1} = m'\cdot g^{xy} \cdot g^{-xy} = m'.</math>
 
=== Practical use ===
 
The ElGamal cryptosystem is usually used in a [[hybrid cryptosystem]]. I.e., the message itself is encrypted using a symmetric cryptosystem and ElGamal is then used
to encrypt the key used for the symmetric cryptosystem. This is because asymmetric cryptosystems like Elgamal are usually slower than symmetric ones, so it is faster to encrypt the symmetric key (which most of the time is quite small if compared to the size of the message) with Elgamal and the message (which can be arbitrarily large) with a symmetric cypher.
 
== Security ==
 
The security of the ElGamal scheme depends on the properties of the underlying group <math>G</math> as well as any padding scheme used on the messages.
 
If the [[computational Diffie–Hellman assumption]] (CDH) holds in the underlying cyclic group <math>G</math>, then the encryption function is [[one-way function|one-way]].<ref name=cryptutor>''CRYPTUTOR'', "[http://crypto.cs.uiuc.edu/wiki/index.php/Elgamal_encryption_scheme Elgamal encryption scheme]"</ref>
 
If the [[decisional Diffie–Hellman assumption]] (DDH) holds in <math>G</math>, then
ElGamal achieves [[semantic security]].<ref name=cryptutor /> Semantic security is not implied by the computational Diffie–Hellman assumption alone.<ref name=DHAES>M. Abdalla, M. Bellare, P. Rogaway, "DHAES, An encryption scheme based on the Diffie–Hellman Problem" (Appendix A)</ref> See [[decisional Diffie–Hellman assumption]] for a discussion of groups where the assumption is believed to hold.
 
ElGamal encryption is unconditionally [[malleability (cryptography)|malleable]], and therefore is not secure under [[chosen ciphertext attack]]. For example, given an encryption <math>(c_1, c_2)</math> of some (possibly unknown) message <math>m</math>, one can easily construct a valid encryption <math>(c_1, 2 c_2)</math> of the message <math>2m</math>.
 
To achieve chosen-ciphertext security, the scheme must be further modified, or an appropriate padding scheme must be used. Depending on the modification, the DDH assumption may or may not be necessary.
 
Other schemes related to ElGamal which achieve security against chosen ciphertext attacks have also been proposed.
The [[Cramer–Shoup cryptosystem]] is secure under chosen ciphertext attack assuming DDH holds for <math>G</math>. Its proof does not use the [[random oracle model]]. Another proposed scheme is DHAES,<ref name=DHAES /> whose proof requires an assumption that is weaker than the DDH assumption.
 
== Efficiency ==
 
ElGamal encryption is [[probabilistic encryption|probabilistic]], meaning that a single [[plaintext]] can be encrypted to many possible ciphertexts, with the consequence that a general ElGamal encryption produces a 2:1 expansion in size from plaintext to ciphertext.
 
Encryption under ElGamal requires two [[exponentiation]]s; however, these exponentiations are independent of the message and can be computed ahead of time if need be. Decryption only requires one exponentiation:
 
=== Decryption ===
The division by <math>s\,</math> can be avoided by using an alternative method for decryption.
To decrypt a ciphertext <math>(c_1,c_2)\,</math> with Alice's private key <math>x\,</math>,
* Alice calculates <math>s'=c_1^{{q-1-x}}=g^{y(q-1-x)}=g^{-xy}</math>.
<math>s'\,</math> is the inverse of <math>s\,</math>. This is a consequence of [[Lagrange's theorem (group theory)|Lagrange's theorem]], because
:<math>s\cdot s' = g^{xy}\cdot g^{y(q-1-x)} = g^{xy}\cdot g^{(-x)y} =1</math>. Note that operations
in the exponent are computed modulo <math>(q-1)</math>, rather than <math>q</math>.
* Alice then computes <math>m'= c_2 \cdot s'</math>, which she then converts back into the plaintext message <math>m\,</math>.
The decryption algorithm produces the intended message, since
:<math> c_2 \cdot s' = m' \cdot s \cdot s' = m' \cdot 1 = m'</math>.
 
==See also==
* [[ElGamal signature scheme]]
* [[Homomorphic encryption]]
 
==References==
<references />
 
* {{cite conference
  | first = Taher
  | last = ElGamal
  | title = A public key cryptosystem and a signature scheme based on discrete logarithms
  | booktitle = Advances in cryptology: Proceedings of CRYPTO 84
  | pages = 10–18
  | volume = 196
  | series = Lecture Notes in Computer Science
  | publisher = Springer-Verlag
  | year = 1985
  | location = Santa Barbara, California, United States
  | url = http://groups.csail.mit.edu/cis/crypto/classes/6.857/papers/elgamal.pdf
  | doi = 10.1007/3-540-39568-7_2}}
* {{cite book |author=A. J. Menezes, P. C. van Oorschot, and S. A. Vanstone |publisher=CRC Press |url=http://www.cacr.math.uwaterloo.ca/hac/about/chap8.pdf |title=Handbook of Applied Cryptography |chapter=Chapter 8.4 ElGamal public-key encryption}}
* {{cite journal |author=[[Dan Boneh]] |title=The Decision Diffie–Hellman Problem |journal=Lecture Notes in Computer Science |year=1998 |volume=1423 |pages=48–63 |doi=10.1007/BFb0054851 |url=http://crypto.stanford.edu/~dabo/abstracts/DDH.html}}
 
{{Cryptography navbox | public-key}}
 
{{DEFAULTSORT:Elgamal Encryption}}
[[Category:Public-key encryption schemes]]

Revision as of 22:28, 6 February 2014

Many men are clueless about what their wives actually need in terms of the materialistic. From final-minute frantic online procuring, to operating via malls in a daze, one can get tangled in a web of confusion in terms of looking for the idyllic gift.

Tire width refers to how broad or how slim is the tire. Having a wider tire will give the car a greater grip on dry pavement; nonetheless, the gas mileage will do worse. Additionally, an excessive amount of width may trigger injury attributable to tires chafing in opposition to the automobile's body. Slender tires have good traction throughout winter; but too narrow can put your safety at greater threat. There should always be sufficient rubber touching the highway for the automotive to maintain going. are making a name for themselves and getting wonderful reviews, so attempt a set at the moment; Grapplers can be found in a huge variety of sizes so you can you should definitely discover some to suit your wheels. Nitto Off Street Tires Nitto Mud Grappler Uneven wear of your tires is likely to be an indication of poor wheel positioning. Learn how to Seal Tire Rims With Ether

Buy entrance wheel drive chrome rims or rear wheel drive truck rims, the products we sell embrace hundreds of chrome wheels to select from. We promote the good kinds in car rims and in addition truck rims. You will save tons of on our prices whenever you purchase automotive wheels and low-cost tires prices in comparison with our opponents. We additionally sell 24 inch rims with superior spinners and truck rims with that deep chrome luster. Whether you need to buy 20 inch customized wheels or 22 inch truck rims, our costs are the lowest around. We promote one low price to your door on all of our automobile rims and custom wheels. In case you are trying to buy chrome rims or truck rims, you will not find a lower price wherever.

When on the lookout for a trailer for sale, keep in mind to search for some very important details. First, a trailer puts additional weight on the automobile, so search for a trailer that is meant for the automobile kind you can be utilizing. After deciding what size of trailer your automobile can haul, there are just a few different issues you must look for. Begin by checking the ware and tear of the tires if they are not new. Then verify for proper tire stress. The hitch and safety chains needs to be effectively inspected to ensure they connect properly. The brakes also should be seemed over for good working situation.

When choosing used tires, you do not know for sure about the history of its usage, whether or not they have been on a car involved in an accident and how had the earlier driver used the tires. Since crap tires have change into an environmental concern because they're illegally dumped in landfills, it is wiser to give them for reuse to your local recycling plant. Fear god, respect humanity and by no means resell your used tires. Chances are you'll be saving a couple of bucks on used tires, however chances are you'll be putting the lives of your passengers and yourself at a huge risk!

Aug 14 FULL AC 35W HIDs Package Particular Sale - Local Store $sixty five (san jose downtown) pic map auto elements - by seller Look at the tires for any signs of wear and tear and tear. Also, test if the tires match in size and model. This article throws gentle on the benefits concerned with purchasing a franchise enterprise for sale and it speaks about the most effective methodology of method to establish the best enterprise opportunity. How one can Properly Rotate Automobile Tires How A lot Air to Put in Tires With a Payload? Quality tires are a key component of driving security regardless of what model Toyota you drive. There are numerous tires from which to choose, together with these recommended by the manufacturer. If you cherished this article and you simply would like to obtain more info regarding purchase tires generously visit our own website. How one can Redeem Your Sears Rebate On-line Specifications for Goodyear Integrity Tires Learn how to Buy Goodyear Fortera Tires

Once you reside in a spot like Denver where you is perhaps sure to see snow within the winter, chances are high you will want to opt for the crossover or all-terrain kind best place to buy tires , which could be a bit extra aggressive tread pattern enabling you to have a better grip on snowy streets and journey the back nation mountain roads a bit more securely. Winter Mud & Snow tires fall primarily into the all-terrain category of tire dimension calculator I am betting that extra people inside the jap United States are wishing they'd a greater all-terrain tire this 12 months with the heavy snow that has pummeled them this winter.

Aug 14 AEM Adjustable Camgears & Cams for '97 Prelude $220 (fremont / union city / newark) pic auto elements - by owner Aug 14 Rial 15 Inch wheels $300 (vallejo / benicia) pic auto components - by owner Aug 14 █ One 18" 245/forty/18 Dunlop SP Sport 01 DSST Run Flat Tire, BMW █ $60 (san mateo) pic auto parts - by owner Aug 14 Ford Mustang T-5 Bell Housing (Put in Once) $a hundred and fifty (san mateo) pic auto components - by proprietor Aug 14 AE86 Corolla Gts Sr5 Supra Celica Wheels $1 pic map auto elements - by proprietor 8000 Aug 14 Porsche 1987 911 chassis $8000 (harmony / pleasant hill / martinez) pic map auto parts - by owner Aug 14 67Olds Cutlass Electric window right door 2door Hardtop, Conv., exc. $400 (twin peaks / diamond hts) auto parts - by owner OBTAINED METRIC TIRES? Divide your metric tire

With the US economy the way in which it is and Sears D+ stability sheet proper now, I do not see any upside there and all draw back in the intervening time, particularly if the broad market sells off which I think is coming again very quickly. The retailing enterprise is all the time a tough enterprise mannequin to be in and with the compounded financial problems for the US client sector, the US retail trade is going to have a tricky time earning profits for shareholders for the foreseeable future in my view.

days ago Mavis Low cost Tire, Fishkill days in the past Mavis Low cost Tire, Greenwich days ago Mavis Low cost Tire, Franklin Square (Hemp tpk) days ago Mavis Discount Tire, Pleasantville Solely 2000 miles however these tires far exceeded my expectations. They are quiet, they handle very effectively and I am very blissful. They are wider than the stock 20 inch tires and shorter however handle significantly better than the originals. The 255/50's are cheaper then the stick measurement but feel so significantly better." - YORKTOWN HEIGHTS, NY days in the past Mavis Low cost Tire, Massapequa Park days ago Mavis Low cost Tire, Franklin Sq. (Franklin ave) days in the past Mavis Low cost Tire, Cicero So far so good. Glorious tires for the price. A really satisfied buyer." - YONKERS, NY days in the past Mavis Low cost Tire, Webster Tire wear and Getting older