Talk:Diffie–Hellman key exchange
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DH is not vulnerable to MITM per seEdit
the Diffie–Hellman exchange by itself does not provide authentication of the communicating parties and is thus vulnerable to a man-in-the-middle attack.
Given that Diffie–Hellman key exchange is anonymous, the example of a MITM attack between Alice, Bob and Mallory doesn't make sense, because Alice doesn't know who she is talking to!
More elaborate exampleEdit
This uses the 2048 bit prime suggested in rfc3526 :
a = (secretly chosen by A, should also be 2048 bit, but shorter here)
b = (secretly chosen by B, should also be 2048 bit, but shorter here)
x = 2^a mod p = (calculated and transmitted by A)
y = 2^b mod p = (calculated and transmitted by B)
KeyA = y^a mod p = 2^(b*a) mod p (calculated by A)
KeyB = x^b mod p = 2^(a*b) mod p (calculated by B)
This is brilliant. Many thanks to the person who contributed this. There are many explanations on how Diffie–Hellman works but when it comes to actually implementing something, it is unclear what p, g and q are and where they come from. This examples clarifies that and should be included on the main page.220.127.116.11 (talk) 04:11, 5 July 2017 (UTC)
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Examples in Sections "explanation" and "Secrecy" using different private numbersEdit
The former section uses a=3 and b=4 while the latter one is using a=6 and b=15 as private numbers. I could not guess any reason for that. Do you agree that it is better to change the latter to use the same private numbers (a=3 and b=4)? Alfa80 (talk) 16:09, 5 November 2017 (UTC)
Needs a section for Elliptic-curve Diffie–HellmanEdit
Please, evaluate to correct the name of the page for issues when citing url which includes "en dashes" in the name.Edit
As some more explained here https://productforums.google.com/forum/#!msg/webmasters/oPsAZ5Dc2hg/sa7I8YCOvxwJ citing this page gives some issues as when copying the url and pasting it, depending where one were working on (e.g. an editor or notepad app) it performs the following url link "https://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exchange" (note the "%E2%80%93" extra for coding the "en dash" (U+2013, –, e2 80 93, EN DASH). Perhaps it helped to change the name including a more standard joining sign in the page name. — Preceding unsigned comment added by 18.104.22.168 (talk) 12:42, 7 January 2018 (UTC)