Canonical Encoding Rules
<protocol, standard> (CER) A restricted variant of BER
for producing unequivocal transfer syntax
for data structures described by ASN.1
gives choices as to how data values may be encoded, CER and DER
select just one encoding from those allowed by the basic encoding rules, eliminating all of the options.
They are useful when the encodings must be preserved, e.g. in security exchanges.
CER and DER
differ in the set of restrictions that they place on the encoder.
The basic difference between CER and DER
is that DER
uses definitive length form and CER uses indefinite length form.
See also PER