O

OFB

See Output Feedback.

OID

Object identifier (ASN.1) for abstract objects specified by ASN.1.

The object identifier is a sequence of integers that identifies objects such as algorithms or attribute types.

See also Abstract Syntax Notation 1.

opaque BLOB

A sequence of bytes used to store session keys. Opaque BLOBs contain the base key material and all current state information. This includes information such as the salt value, the initialization vector, and the key table. The format of opaque BLOBs is unpublished. Each CSP vendor determines its own BLOB format which should include encrypting the opaque BLOBs with some sort of symmetric key.

outer content

The enhancements for some encapsulated data. This term is used primarily when discussing enhanced data (the inner content) in PKCS #7 messages.

Output Feedback

(OFB) A block cipher mode that uses feedback similar to the Cipher Feedback (CFB) mode. The only difference between the two modes is how the shift register is filled.

See also Cipher Feedback.