+4. To generate an EC key
+
+An EC key can be used both for key agreement (ECDH) and signing (ECDSA).
+
+Generating a key for ECC is similar to generating a DSA key. These are
+two-step processes. First, you have to get the EC parameters from which
+the key will be generated:
+
+ openssl ecparam -name prime256v1 -out prime256v1.pem
+
+The prime256v1, or NIST P-256, which stands for 'X9.62/SECG curve over
+a 256-bit prime field', is the name of an elliptic curve which generates the
+parameters. You can use the following command to list all supported curves:
+
+ openssl ecparam -list_curves
+
+When that is done, you can generate a key using the created parameters (several
+keys can be produced from the same parameters):
+
+ openssl genpkey -des3 -paramfile prime256v1.pem -out private.key
+
+With this variant, you will be prompted for a password to protect your key.
+If you don't want your key to be protected by a password, remove the flag
+'-des3' from the command line above.
+
+You can also directly generate the key in one step:
+
+ openssl ecparam -genkey -name prime256v1 -out private.key
+
+or
+
+ openssl genpkey -algorithm EC -pkeyopt ec_paramgen_curve:P-256
+
+
+5. NOTE
+
+If you intend to use the key together with a server certificate,
+it may be reasonable to avoid protecting it with a password, since
+otherwise someone would have to type in the password every time the
+server needs to access the key.
+
+For X25519 and X448, it's treated as a distinct algorithm but not as one of
+the curves listed with 'ecparam -list_curves' option. You can use
+the following command to generate an X25519 key:
+
+ openssl genpkey -algorithm X25519 -out xkey.pem