!!! Overview 
[{$pagename}] ([DER]) is an [ASN.1] subset of [Basic Encoding Rules], and give exactly one way to represent any [ASN.1] value as an [Octet String]. 

[{$pagename}] is intended for applications in which a unique octet string [encoding] is needed, as is the case when a digital signature is computed on an ASN.1 value. DER is defined in Section 8.7 of X.509.

[{$pagename}]  adds the following restrictions to the rules given in [Basic Encoding Rules|Basic Encoding Rules]:
* When the length is between 0 and 127, the short form of length must be used
* When the length is 128 or greater, the long form of length must be used, and the length must be encoded in the minimum number of octets.
* For simple string types and implicitly tagged types derived from simple string types, the primitive, definite-length method must be employed.
* For structured types, implicitly tagged types derived from structured types, and explicitly tagged types derived from anything, the constructed, definite-length method must be employed.
* Other restrictions are defined for particular types (such as BIT STRING, SEQUENCE, SET, and SET OF) as defined within the [ASN.1] specifications.!! [{$pagename}] [Certificate Format]
DER is a [Binary] form of [ASCII] [PEM] [Certificate Format]. All types of [Certificates] & [Private Keys] can be encoded in [DER] format.

[{$pagename}] [Certificate Format] Characteristics:

* This format supports storage of single certificate (does __NOT__ include [Private Key] for the [Certificate Chain]) 
* They are [Binary] format files
* [File System] extensions are usually: .cer and .der
* DER is typically used in Java platform

!! More Information
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[{ReferringPagesPlugin before='*' after='\n' }]