Public Key Authentication - Revision history

Larocqt at 15:20, 11 April 2009

2009-04-11T15:20:31Z

← Older revision		Revision as of 15:20, 11 April 2009
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	==Public Key Algorithms==		==Public Key Algorithms==

-	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication.<sup>[3, 4]</sup> The RSA and Diffie-Hellman algorithms are the most commonly used algorithms in public key authentication.<sup>[4]<sup>	+	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication.<sup>[3, 4]</sup> The RSA and Diffie-Hellman algorithms are the most commonly used algorithms in public key authentication.<sup>[4]</sup>

	* Primes		* Primes

Larocqt at 15:18, 11 April 2009

2009-04-11T15:18:46Z

← Older revision		Revision as of 15:18, 11 April 2009
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	Messages are encrypted using the public key, and may only be decrypted by the corresponding private key. In this way, possession of the private key is required for the message to be read and third parties are prevented from intercepting the message. Similarly, the private key can generate unique signatures that could only have come from that specific private key. Using the matching public key a server can verify the signature provided and therefore the user's identity.		Messages are encrypted using the public key, and may only be decrypted by the corresponding private key. In this way, possession of the private key is required for the message to be read and third parties are prevented from intercepting the message. Similarly, the private key can generate unique signatures that could only have come from that specific private key. Using the matching public key a server can verify the signature provided and therefore the user's identity.
		+
		+	[[Image:key.jpg\|thumb\|500px\|right\|Public Key Authentication]]

	==Background==		==Background==
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-	--[[User:larocqt\|larocqt]] 1:56 AM, 10 April 2009 (EDT)	+	--[[User:larocqt\|larocqt]] 11:18 AM, 11 April 2009 (EDT)

Larocqt at 05:58, 10 April 2009

2009-04-10T05:58:30Z

← Older revision		Revision as of 05:58, 10 April 2009
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	==Public Key Algorithms==		==Public Key Algorithms==

-	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication. <sup>[3, 4]</sup>The RSA and Diffie-Hellman algorithms are the most commonly used algorithms in public key authentication	+	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication.<sup>[3, 4]</sup> The RSA and Diffie-Hellman algorithms are the most commonly used algorithms in public key authentication.<sup>[4]<sup>

	* Primes		* Primes

Larocqt at 05:56, 10 April 2009

2009-04-10T05:56:57Z

← Older revision		Revision as of 05:56, 10 April 2009
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	==Public Key Algorithms==		==Public Key Algorithms==

-	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication.<sup>[3, 4]</sup>	+	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication. <sup>[3, 4]</sup>The RSA and Diffie-Hellman algorithms are the most commonly used algorithms in public key authentication

	* Primes		* Primes
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	** RSA (Rivest-Shamir-Adleman) algorithm		** RSA (Rivest-Shamir-Adleman) algorithm
	* Discrete Logarithms		* Discrete Logarithms
-	** DSA/DSS (Digital Signature Standard) algorithm
	** Diffie-Hellman algorithm		** Diffie-Hellman algorithm
		+	** DSA/DSS (Digital Signature Standard) algorithm
	* Lattices		* Lattices
	* [[Digital Signatures]]		* [[Digital Signatures]]
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-	--[[User:larocqt\|larocqt]] 11:~~53 PM~~, 9 April 2009 (EDT)	+	--[[User:larocqt\|larocqt]] 1:56 AM, 10 April 2009 (EDT)

Larocqt at 05:53, 10 April 2009

2009-04-10T05:53:14Z

← Older revision		Revision as of 05:53, 10 April 2009
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	===Message Encryption/Decryption Process===		===Message Encryption/Decryption Process===

-	[[Image:~~encryption~~.jpg\|thumb\|350px\|right\|Process for encrypting and decrypting message in public key authentication]]	+	[[Image:encrypt.jpg\|thumb\|350px\|right\|Process for encrypting and decrypting message in public key authentication]]
	* Generate a key pair on your computer		* Generate a key pair on your computer
	* Send your public key to the desired user you wish to communicate with		* Send your public key to the desired user you wish to communicate with

Larocqt at 05:52, 10 April 2009

2009-04-10T05:52:42Z

← Older revision		Revision as of 05:52, 10 April 2009
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	===Identity Verification Process===		===Identity Verification Process===

		+	[[Image:signature.jpg\|thumb\|350px\|right\|Process for verifying identity in public key authentication]]
	* Generate a key pair on your computer		* Generate a key pair on your computer
	* Copy your public key to the server		* Copy your public key to the server
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	===Message Encryption/Decryption Process===		===Message Encryption/Decryption Process===

		+	[[Image:encryption.jpg\|thumb\|350px\|right\|Process for encrypting and decrypting message in public key authentication]]
	* Generate a key pair on your computer		* Generate a key pair on your computer
	* Send your public key to the desired user you wish to communicate with		* Send your public key to the desired user you wish to communicate with

Larocqt at 03:53, 10 April 2009

2009-04-10T03:53:47Z

← Older revision		Revision as of 03:53, 10 April 2009
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	The process of message delivery in networking resembles the postal system of the physical world. Encryption of the messages themselves is like locking the parcel with a padlock. Using a symmetric key would involve a single padlock with each user possessing an identical copy of the key used to open that padlock.		The process of message delivery in networking resembles the postal system of the physical world. Encryption of the messages themselves is like locking the parcel with a padlock. Using a symmetric key would involve a single padlock with each user possessing an identical copy of the key used to open that padlock.

-	Alternatively, the use of a public (asymmetric) key system is equivalent to each user purchasing their own key/padlock set and sending the padlock to the user with whom they wish to communicate. This second user would then use this received padlock to lock up any messages they wish to send. The first user then unlocks the padlock with the matching key that they remained in possession of the entire time.	+	Alternatively, the use of a public (asymmetric) key system is equivalent to each user purchasing their own key/padlock set and sending the padlock to the user with whom they wish to communicate. This second user would then use this received padlock to lock up any messages they wish to send. The first user then unlocks the padlock with the matching key that they remained in possession of the entire time.<sup>[1]</sup>

	==History==		==History==

-	Although the first asymmetric key algorithm was published in 1976 by Whitfield Diffie and Martin Hellman, a similar such cryptography had already been invented independently by James H. Ellis, Clifford Cocks, and Malcolm Williamson in the early 1970s due to the fact that Ellis, Cocks, and Williamson work was done for Britain's Government Communications Headquarters and was kept confidential until 1997.	+	Although the first asymmetric key algorithm was published in 1976 by Whitfield Diffie and Martin Hellman, a similar such cryptography had already been invented independently by James H. Ellis, Clifford Cocks, and Malcolm Williamson in the early 1970s due to the fact that Ellis, Cocks, and Williamson work was done for Britain's Government Communications Headquarters and was kept confidential until 1997.<sup>[1]</sup>

-	These were soon followed by the invention of the RSA algorithm by Ron Rivest, Adi Shamir, and Leonard Adleman in 1977 as well many more schemes over the previous three decades.	+	These were soon followed by the invention of the RSA algorithm by Ron Rivest, Adi Shamir, and Leonard Adleman in 1977 as well many more schemes over the previous three decades.<sup>[1]</sup>

	==Benefits==		==Benefits==
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	===Hacked Server===		===Hacked Server===

-	One advantage the public key authentication possesses over those that are password-based is when the server has been hacked or spoofed. In systems that use symmetric keys for authentication, the attacker can learn your password and proceed to pose as you in the future. Alternatively, if a server using public key authentication is hacked the signature sent to the server would mean nothing to the attacker. Without the private key, the attacker cannot impersonate you.	+	One advantage the public key authentication possesses over those that are password-based is when the server has been hacked or spoofed. In systems that use symmetric keys for authentication, the attacker can learn your password and proceed to pose as you in the future. Alternatively, if a server using public key authentication is hacked the signature sent to the server would mean nothing to the attacker. Without the private key, the attacker cannot impersonate you.<sup>[2]</sup>

	===Brute Force Attacks===		===Brute Force Attacks===
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	==Public Key Algorithms==		==Public Key Algorithms==

-	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication.	+	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication.<sup>[3, 4]</sup>

	* Primes		* Primes
-
	* Factoring		* Factoring
	** RSA (Rivest-Shamir-Adleman) algorithm		** RSA (Rivest-Shamir-Adleman) algorithm
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	==References==		==References==

		+	# "[http://en.wikipedia.org/wiki/Public-key_cryptography Public Key Cryptography]" 2009-04-05.
	# "[http://the.earth.li/~sgtatham/putty/0.55/htmldoc/Chapter8.html#S8.2.8 Using Public Keys for SSH Authentication]". Retrieved 2009-04-05.		# "[http://the.earth.li/~sgtatham/putty/0.55/htmldoc/Chapter8.html#S8.2.8 Using Public Keys for SSH Authentication]". Retrieved 2009-04-05.
	# [http://www.infosecwriters.com/text_resources/pdf/Public_Key_Cryptography_AMS.pdf Public Key Cryptography: Applications Algorithms and Mathematical Explanations], Anoop MS (2007).		# [http://www.infosecwriters.com/text_resources/pdf/Public_Key_Cryptography_AMS.pdf Public Key Cryptography: Applications Algorithms and Mathematical Explanations], Anoop MS (2007).
-	~~# "[http://en.wikipedia.org/wiki/Public-key_cryptography Public Key Cryptography]" 2009-04-05.~~
	# "[http://www.ssh.com/support/cryptography/algorithms/asymmetric.html Public Key Cryptosystems: Asymmetric Ciphers]". Retrieved 2009-04-05.		# "[http://www.ssh.com/support/cryptography/algorithms/asymmetric.html Public Key Cryptosystems: Asymmetric Ciphers]". Retrieved 2009-04-05.

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-	--[[User:larocqt\|larocqt]] 11:~~02 AM~~, 5 April 2009 (EDT)	+	--[[User:larocqt\|larocqt]] 11:53 PM, 9 April 2009 (EDT)

Larocqt at 03:44, 10 April 2009

2009-04-10T03:44:04Z

← Older revision		Revision as of 03:44, 10 April 2009
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	==Background==		==Background==

-	*briefly explain password-based/symmetric key authentication	+	The idea behind the use public keys is to create a secure system of authentication which prevents third parties from hacking into one of the participants' systems and gaining access to any sensitive information that is transferred. The use of complex schemes to separately generate the private and public keys go a long way in preventing this from happening. Even though the public key is freely distributed, the key pair is generated in such a way that the private key cannot be derived should the public key fall into the wrong hands. Since the private key does all of the important work regarding sensitive material (decrypting messages, generating signatures to confirm identity) the public key is useless to those seeking to use it for malicious purposes.
-	*go in ~~more detail on public key authentication~~	+
		+	This is not the case with password-based authentication, also known as symmetric key authentication in which only the one password is used for all encryption. Should an attacker obtain this password, there is no telling the damage they can do.

	===Identity Verification Process===		===Identity Verification Process===
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	* Recipient uses their private key to decrypt the message		* Recipient uses their private key to decrypt the message

-	===Physical World ~~Equivalent~~===	+	===Physical World Equivalents===

	The process of message delivery in networking resembles the postal system of the physical world. Encryption of the messages themselves is like locking the parcel with a padlock. Using a symmetric key would involve a single padlock with each user possessing an identical copy of the key used to open that padlock.		The process of message delivery in networking resembles the postal system of the physical world. Encryption of the messages themselves is like locking the parcel with a padlock. Using a symmetric key would involve a single padlock with each user possessing an identical copy of the key used to open that padlock.

	Alternatively, the use of a public (asymmetric) key system is equivalent to each user purchasing their own key/padlock set and sending the padlock to the user with whom they wish to communicate. This second user would then use this received padlock to lock up any messages they wish to send. The first user then unlocks the padlock with the matching key that they remained in possession of the entire time.		Alternatively, the use of a public (asymmetric) key system is equivalent to each user purchasing their own key/padlock set and sending the padlock to the user with whom they wish to communicate. This second user would then use this received padlock to lock up any messages they wish to send. The first user then unlocks the padlock with the matching key that they remained in possession of the entire time.
		+
		+	==History==
		+
		+	Although the first asymmetric key algorithm was published in 1976 by Whitfield Diffie and Martin Hellman, a similar such cryptography had already been invented independently by James H. Ellis, Clifford Cocks, and Malcolm Williamson in the early 1970s due to the fact that Ellis, Cocks, and Williamson work was done for Britain's Government Communications Headquarters and was kept confidential until 1997.
		+
		+	These were soon followed by the invention of the RSA algorithm by Ron Rivest, Adi Shamir, and Leonard Adleman in 1977 as well many more schemes over the previous three decades.

	==Benefits==		==Benefits==
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	==Public Key Algorithms==		==Public Key Algorithms==

-	There are many different algorithms used to generate the private and public keys in asymmetric key authentication.	+	There are many different algorithms that can be used to generate the private and public keys in asymmetric key authentication.

	* Primes		* Primes
		+
	* Factoring		* Factoring
	** RSA (Rivest-Shamir-Adleman) algorithm		** RSA (Rivest-Shamir-Adleman) algorithm
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	==References==		==References==

-	# "[http://the.earth.li/~sgtatham/putty/0.55/htmldoc/Chapter8.html#S8.2.8 Using Public Keys for SSH Authentication]". Retrieved ...	+	# "[http://the.earth.li/~sgtatham/putty/0.55/htmldoc/Chapter8.html#S8.2.8 Using Public Keys for SSH Authentication]". Retrieved 2009-04-05.
-	# [http://www.infosecwriters.com/text_resources/pdf/Public_Key_Cryptography_AMS.pdf Public Key Cryptography: Applications Algorithms and Mathematical Explanations], Anoop MS.	+	# [http://www.infosecwriters.com/text_resources/pdf/Public_Key_Cryptography_AMS.pdf Public Key Cryptography: Applications Algorithms and Mathematical Explanations], Anoop MS (2007).
-	# "[http://en.wikipedia.org/wiki/Public-key_cryptography Public Key Cryptography]" ...	+	# "[http://en.wikipedia.org/wiki/Public-key_cryptography Public Key Cryptography]" 2009-04-05.
-	# "[http://www.ssh.com/support/cryptography/algorithms/asymmetric.html Public Key Cryptosystems: Asymmetric Ciphers]". Retrieved ...	+	# "[http://www.ssh.com/support/cryptography/algorithms/asymmetric.html Public Key Cryptosystems: Asymmetric Ciphers]". Retrieved 2009-04-05.
-		+

	==See Also==		==See Also==

-	[[Digital Signatures]]	+	* [[Digital Signatures]]

	==External Links==		==External Links==

Larocqt at 02:18, 10 April 2009

2009-04-10T02:18:45Z

← Older revision		Revision as of 02:18, 10 April 2009
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	==References==		==References==

-	*[http://the.earth.li/~sgtatham/putty/0.55/htmldoc/Chapter8.html#S8.2.8~~] -~~ Using Public ~~Key~~ Authentication	+	# "[http://the.earth.li/~sgtatham/putty/0.55/htmldoc/Chapter8.html#S8.2.8 Using Public Keys for SSH Authentication]". Retrieved ...
-	*[http://www.infosecwriters.com/text_resources/pdf/Public_Key_Cryptography_AMS.pdf~~] -~~ Public Key Cryptography	+	# [http://www.infosecwriters.com/text_resources/pdf/Public_Key_Cryptography_AMS.pdf Public Key Cryptography: Applications Algorithms and Mathematical Explanations], Anoop MS.
-	*[http://en.wikipedia.org/wiki/Public-key_cryptography~~] -~~ Public Key Cryptography	+	# "[http://en.wikipedia.org/wiki/Public-key_cryptography Public Key Cryptography]" ...
-	*[http://www.ssh.com/support/cryptography/algorithms/asymmetric.html~~] -~~ Asymmetric Ciphers	+	# "[http://www.ssh.com/support/cryptography/algorithms/asymmetric.html Public Key Cryptosystems: Asymmetric Ciphers]". Retrieved ...


	==See Also==		==See Also==
		+
		+	[[Digital Signatures]]

	==External Links==		==External Links==

Larocqt at 15:05, 5 April 2009

2009-04-05T15:05:29Z

← Older revision		Revision as of 15:05, 5 April 2009
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	** Diffie-Hellman algorithm		** Diffie-Hellman algorithm
	* Lattices		* Lattices
-	* [[Digital ~~signatures~~]]	+	* [[Digital Signatures]]

	==References==		==References==