Please tell me of the accuracy of this statement: You don't run the keys on emails rather you run the keys over data you may send as an attachment. :-)~MIKE~(-: On Mon, Feb 16, 2015 at 8:35 PM, Stephen Partington wrote: > The public key is meant to be available to sign data for that person. you > do this so they can un-encrypt the data but they know it was signed. and > only they can un-encrypt that data. > > On Mon, Feb 16, 2015 at 8:28 PM, Michael Havens wrote: > >> That is where I was befuddled. I didn't realize that the public/private >> keys belonged to the same person. So when we get a message with a key on it >> that is the public key and everyone has access to it and that will >> encrypt/decrypt a message if we know how to use it.. And then originator of >> the key has the private key to do the opposite as was done to the message >> before it was sent. >> >> :-)~MIKE~(-: >> >> On Mon, Feb 16, 2015 at 8:18 PM, Stephen Partington > > wrote: >> >>> Stolen but relevant. >>> >>> The Public and Private key pair comprise of two uniquely related >>> cryptographic keys (basically long random numbers). Below is an example of >>> a Public Key: >>> >>> 3048 0241 00C9 18FA CF8D EB2D EFD5 FD37 89B9 E069 EA97 FC20 5E35 F577 >>> EE31 C4FB C6E4 4811 7D86 BC8F BAFA 362F 922B F01B 2F40 C744 2654 C0DD 2881 >>> D673 CA2B 4003 C266 E2CD CB02 0301 0001 >>> >>> The Public Key is what its name suggests - Public. It is made available >>> to everyone via a publicly accessible repository or directory. On the other >>> hand, the Private Key must remain confidential to its respective owner. >>> >>> Because the key pair is mathematically related, whatever is encrypted >>> with a Public Key may only be decrypted by its corresponding Private Key >>> and vice versa. >>> >>> For example, if Bob wants to send sensitive data to Alice, and wants to >>> be sure that only Alice may be able to read it, he will encrypt the data >>> with Alice's Public Key. Only Alice has access to her corresponding Private >>> Key and as a result is the only person with the capability of decrypting >>> the encrypted data back into its original form. >>> >>> As only Alice has access to her Private Key, it is possible that only >>> Alice can decrypt the encrypted data. Even if someone else gains access to >>> the encrypted data, it will remain confidential as they should not have >>> access to Alice's Private Key. >>> >>> From >>> https://www.comodo.com/resources/small-business/digital-certificates2.php >>> On Feb 16, 2015 7:57 PM, "Michael Havens" wrote: >>> >>>> no.... no..... Joseph says it is like two locks.When you unlock one you >>>> lock the other? hmmmm.... >>>> >>>> :-)~MIKE~(-: >>>> >>>> On Mon, Feb 16, 2015 at 7:49 PM, Michael Havens >>>> wrote: >>>> >>>>> and then the public key everyone can see and the private one only you >>>>> can see? >>>>> >>>>> :-)~MIKE~(-: >>>>> >>>>> On Mon, Feb 16, 2015 at 7:45 PM, Michael Havens >>>>> wrote: >>>>> >>>>>> is a real simplified version that it is like two locks locked >>>>>> together and each key opens one of the locks? >>>>>> >>>>>> :-)~MIKE~(-: >>>>>> >>>>>> On Mon, Feb 9, 2015 at 7:05 PM, Joseph Sinclair < >>>>>> plug-discussion@stcaz.net> wrote: >>>>>> >>>>>>> Lots of confusion here. Let me try to clarify (a small amount). >>>>>>> >>>>>>> Background: >>>>>>> "Public Key" cryptography is also called "Asymmetric Cryptography". >>>>>>> The reason is that there are two different keys, and they only work >>>>>>> together in an "asymmetric" fashion (whatever one key does, the other key >>>>>>> undoes). >>>>>>> The keys are "related" mathematically, but it is (currently) not >>>>>>> possible to figure out one key from the other (so having a public key does >>>>>>> not help you determine the private key). >>>>>>> >>>>>>> 1) There are two keys. >>>>>>> a) There are also two *actions*, encryption (hiding content from >>>>>>> unauthorized viewers) and verification (proving a message is authentic and >>>>>>> from a known entity). >>>>>>> 2) *Either* key can be used to encrypt, but the *other* key is >>>>>>> needed to decrypt. >>>>>>> a) that means public(encrypt) ==> private(decrypt) *or* >>>>>>> private(encrypt) ==> public(decrypt). >>>>>>> b) a single key cannot both encrypt and decrypt the same message >>>>>>> (That's why it's called "asymmetric encryption", the keys are *not* >>>>>>> interchangeable). >>>>>>> 3) The "Public" key is meant to be published far and wide. It is >>>>>>> used to encrypt a message intended for the key "owner", and it is also used >>>>>>> (by decrypting a hash) to "verify" that a message was sent by the real >>>>>>> owner (signature). >>>>>>> 4) The "Private" key is meant to be kept strictly secret. It can >>>>>>> decrypt any message encrypted by the public key. It can also encrypt a >>>>>>> message that only the "Public" key can decrypt (see signature below). >>>>>>> >>>>>>> Encryption is the function most people understand (it's also very >>>>>>> rarely used**). You encrypt a message using the "Public" key as the >>>>>>> encryption key. >>>>>>> Once encrypted the data is essentially static to anyone who does not >>>>>>> possess the "Private" key. >>>>>>> There are a ton of details involved, so it's rarely explained >>>>>>> further than that without reading an entire textbook (or 3). >>>>>>> >>>>>>> There is a *related* function called "verification" or "Digital >>>>>>> Signature". This is used to prove (without ever exposing a secret) that a >>>>>>> particular entity possesses the secret "Private" key. >>>>>>> This is how you know your HTTPS connection is connected to the >>>>>>> correct endpoint rather than some imposter (it's also how ssh passwordless >>>>>>> login works). >>>>>>> This involves (very simplified) using the "Private" key to encrypt >>>>>>> the hash of a message (to sign the message) or a "nonce" value (to verify >>>>>>> endpoint identity, e.g. SSL). >>>>>>> Once the value (hash or nonce) is encrypted by the "Private" key, >>>>>>> only the matching "Public" key will decrypt it. >>>>>>> So if someone sent you a message and it's encrypted hash, then you >>>>>>> decrypt the hash with the "Public" key, and if it decrypts correctly you >>>>>>> know it is valid. >>>>>>> Of course, you would also hash the message (there are standard >>>>>>> algorithms for generating these "hash" values) and see if your results >>>>>>> match what you decrypted (if they don't, then the message isn't what the >>>>>>> sender meant to send). >>>>>>> >>>>>>> There are several ways of implementing assymetric cryptography, the >>>>>>> most commonly used is with the RSA family of algorithms. >>>>>>> The "elliptic curve" (or "EC") family of algorithms have grown in >>>>>>> popularity in recent years, but are still only occasionally used. >>>>>>> The two are mostly different in the mathematics behind how and why >>>>>>> they work. >>>>>>> The basic concepts (two keys, two operations, what one key does the >>>>>>> other undoes) are the same. >>>>>>> >>>>>>> Hopefully that helps a bit. >>>>>>> >>>>>>> Public Key Cryptography (and Asymmetric Cryptography in general) is >>>>>>> a huge and complex topic, so I second Todd's suggestion that if you want to >>>>>>> really understand this, you will want to read a few good textbooks on the >>>>>>> subject. >>>>>>> >>>>>>> ==Joseph++ >>>>>>> >>>>>>> ** Some will say that SSL uses public key encryption. This is true, >>>>>>> but misleading, because the public key encryption is only used during the >>>>>>> "handshake" where the SSL connection is setup to encrypt the exchange of >>>>>>> symmetric keys. This "key exchange" is what Diffie and Helman invented >>>>>>> that makes modern PKI possible. >>>>>>> The encryption that does all the heavy lifting of keeping the SSL >>>>>>> tunnel secure is always a "block" (symmetric) algorithm, most commonly AES >>>>>>> (for modern systems where security is properly implemented) or 3DES >>>>>>> (slightly older but still pretty secure) or RC4 (completely insecure and >>>>>>> used by extremely badly managed sites running ancient and horribly flawed >>>>>>> web server software, unfortunately there are still far too many very large >>>>>>> businesses that do this). >>>>>>> >>>>>>> >>>>>>> On 02/09/2015 06:01 PM, Michael Havens wrote: >>>>>>> > helps some but you state: >>>>>>> > >>>>>>> > you want others to be able to check that you actually >>>>>>> > sent the message (by using your public key) >>>>>>> > >>>>>>> > Where do they get your public key? >>>>>>> > How does your public key and private key decrypt when it seems the >>>>>>> public >>>>>>> > key changes. >>>>>>> > >>>>>>> > :-)~MIKE~(-: >>>>>>> > >>>>>>> > On Mon, Feb 9, 2015 at 5:48 PM, someone wrote: >>>>>>> > >>>>>>> >> So if I'm right calling it a 'key' is a misnomer. I am a very >>>>>>> literal >>>>>>> >> person. if they call it a key it unlocks things, not creates them. >>>>>>> >> That is where my confusion is from. Am I correct? >>>>>>> >> >>>>>>> >> Not quite correct... >>>>>>> >> >>>>>>> >> Both the public and private keys ARE keys... they're just used a >>>>>>> >> little differently. >>>>>>> >> >>>>>>> >> You keep your private key secure, and use it to digitally sign a >>>>>>> >> message when you want others to be able to check that you actually >>>>>>> >> sent the message (by using your public key). Others can send an >>>>>>> >> encrypted message that only you can decode, by encrypting the >>>>>>> message >>>>>>> >> using your public key. When you get the message, you can use your >>>>>>> >> private key to undo the encryption that was done using your public >>>>>>> >> key. >>>>>>> >> >>>>>>> >> So, in a way, the public and private keys can be thought of as two >>>>>>> >> pieces of a single, combined key. The software that does the >>>>>>> signing >>>>>>> >> or encryption (using the keys), such as gnupg, pgp, etc., is more >>>>>>> like >>>>>>> >> the lock that the keys fit. >>>>>>> >> >>>>>>> >> I hope that helps. >>>>>>> >> -- >>>>>>> >> Kevin O'Connor >>>>>>> >> >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> > --------------------------------------------------- >>>>>>> > PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >>>>>>> > To subscribe, unsubscribe, or to change your mail settings: >>>>>>> > http://lists.phxlinux.org/mailman/listinfo/plug-discuss >>>>>>> > >>>>>>> >>>>>>> >>>>>>> --------------------------------------------------- >>>>>>> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >>>>>>> To subscribe, unsubscribe, or to change your mail settings: >>>>>>> http://lists.phxlinux.org/mailman/listinfo/plug-discuss >>>>>>> >>>>>> >>>>>> >>>>> >>>> >>>> --------------------------------------------------- >>>> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >>>> To subscribe, unsubscribe, or to change your mail settings: >>>> http://lists.phxlinux.org/mailman/listinfo/plug-discuss >>>> >>> >>> --------------------------------------------------- >>> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >>> To subscribe, unsubscribe, or to change your mail settings: >>> http://lists.phxlinux.org/mailman/listinfo/plug-discuss >>> >> >> >> --------------------------------------------------- >> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >> To subscribe, unsubscribe, or to change your mail settings: >> http://lists.phxlinux.org/mailman/listinfo/plug-discuss >> > > > > -- > A mouse trap, placed on top of your alarm clock, will prevent you from > rolling over and going back to sleep after you hit the snooze button. > > Stephen > > > --------------------------------------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org > To subscribe, unsubscribe, or to change your mail settings: > http://lists.phxlinux.org/mailman/listinfo/plug-discuss >