!!! Overview
[{$pagename}] ([SHA256withECDSA] [1.2.840.10045.4.3.2]) is an [Asymmetric Key Cryptography] [algorithm] [Elliptic Curve Digital Signature Algorithm] using [P-256] and [SHA-256]


[RFC 7518] defines the use of [ECDSA] with the [P-256] curve and the [SHA-256] [Cryptographic Hash Function], [ECDSA] with the [P-384] curve and the [SHA-384] [Cryptographic Hash Function], and ECDSA with the [P-521] curve and the [SHA-512] [Cryptographic Hash Function].  
The ECDSA P-256 SHA-256 digital signature is generated as follows:
* Generate a [Digital Signature] of the [JSON Web Signature] ([JWS]) Signing Input using [ECDSA] [P-256] [SHA-256] with the desired [Private Key].  The output will be the pair (R, S), where R and S are 256-[bit] unsigned [integers].
* Turn R and S into octet sequences in [Big-Endian] order, with each array being be 32 [Octet] long.  The [octet] sequence representations [MUST NOT] be shortened to omit any leading zero octets contained in the values.
* Concatenate the two octet sequences in the order R and then S. (Note that many ECDSA implementations will directly produce this concatenation as their output.)
* The resulting 64-octet sequence is the [JWS] Signature value.


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