!!! Overview
The [{$pagename}] method of [Key-Exchange] consists of three messages.  

%%warning
STATIC [{$pagename}] is [Deprecated] in [TLS 1.3] 
%%

First the [ServerKeyExchange] where the server sends to the client an [RSA] [Public Key], K_T, to which the server holds the [Private Key]. This may be a transient key generated solely for this connection, or it may be re-used for several connections.

Second [ClientKeyExchange] where the client generates a string of random bytes, K, encrypts it using K_T, and sends the result back to the server, which decrypts it.  

Then both the client and server each hash K, K_T, and the various [Key-Exchange]  parameters to generate the exchange hash, H, which is used to generate the [encryption] keys for the session, and the server signs H with its host key and sends the [Digital Signature] to the client.

Then the client then verifies the host key.

!! [Authentication] with [{$pagename}]
With static [{$pagename}]s, the connection is authenticated by encrypting the [premaster Secret] with the server [certificate]’s [Public Key]. Only the server in possession of the [Private Key] can decrypt, correctly derive the [Master Secret], and send an encrypted Finished message with the right [MAC].

The simplicity of static [{$pagename}] has a serious drawback: it does not offer [Perfect Forward Secrecy]. If a [observer] adversary records all traffic to a server then every recorded [TLS] session can be broken later by obtaining the [certificate]’s [Private Key].

!! More Information
There might be more information for this subject on one of the following:
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