[What] is this part of DH Key Exchange

[romeoromeo]

Originally Posted by Zeroxelli

Because, the common point isn't the key itself, it's just the beginning point. And it's by code. Yellow is just a representation, it has no color.

that is where the confusing ..... its known by code ..... so both already have the ( BEGAINING) P and G .... why i send it if they already know it
and .... do you mean that common point the secret key ( result of all that exchange process ? )

[pro4never]

The P/G are used to generate keys. They can either be

A: Transmitted as part of the exchange or
B: Hard coded inside the client and server

Once the Client and server have the same P/G the secret key can be transmitted by generating a shared key which takes into account the P/G and secret key. Reversing the math used to generate the shared key allows the second computer to have the same secret key as the sender.

[romeoromeo]

Originally Posted by pro4never

The P/G are used to generate keys. They can either be

A: Transmitted as part of the exchange or
B: Hard coded inside the client and server

Once the Client and server have the same P/G the secret key can be transmitted by generating a shared key which takes into account the P/G and secret key. Reversing the math used to generate the shared key allows the second computer to have the same secret key as the sender.

ok in the case A ... transmitted as part of the exchange ...
the key exchange is used to set the encryption .
how will the reciver decryp it ???? they are not have the same encryption yet ?

by the way .... i read the thread you linked here .... and i asked you there a question also

[pro4never]

They are using the same encryption as the keys are not applied until after the key exchange... that's what the key exchange is FOR... to establish the keys used for encryption.