Online SNIA Dictionary

[Network] 

Acronym for User Datagram Protocol.

Acronym for Upper Layer Protocol.

[SCSI] 

A form of SCSI capable of 40 megatransfers per second.

There is no single ended Ultra2 SCSI specification. Low voltage differential (LVD) Ultra2 SCSI supports bus lengths of up to 12 meters. High voltage differential Ultra2 SCSI supports bus lengths of up to 25 meters. Ultra2 SCSI specifications define both narrow (8 data bits) and wide (16 data bits) buses. A narrow Ultra SCSI interconnect transfers data at a maximum of 40 MBytes per second. A wide Ultra2 SCSI interconnect transfers data at a maximum of 80 MBytes per second.

[Storage System] 

The half-inch, 'square' tape implementation of the LTO format, currently in its 4th generation, LTO-4 Ultrium.

[Data Security] 

The exposure of information to individuals not authorized to receive or access it.

[General] 

A set of standards intended to allow representation of every character in each of the world's languages; usually understood to mean the 16-bit variant.

Sixteen-bit Unicode allows for up to 2¹⁶, or 65,536 characters, each of which may have a unique representation. It accommodates numerous non-English character sets and symbols, and is therefore an aid to development of products with multilingual user interfaces. Sixteen bits are not enough, however, to represent all the several hundred thousand Asian ideograms. Other 32-bit variants are available for these, but the increased inefficiency in representation of Western text inherent in them has been a barrier to widespread adoption.

[Management] 

A visual approach that uses a variety of diagrams such as use case, class, interaction, state, activity and others to specify the objects of a model and their relationships.

Various tools exist for turning UML diagrams into program code.

URL

Compact sequence of characters that identifies an abstract or physical resource, including its location.

See RFC1738.

[Storage System]  [Operating System] 

See trim.

Removal of the virtual addresses from a portion of a file (e.g., POSIX).

An information category indicated in a Fibre Channel frame header.

A protocol used on a Fibre Channel network at or above the FC-4 level.

The Fibre Channel Protocol for SCSI and IP over Fibre Channel are examples of ULPs.

[Storage System] 

Synonym for formatted capacity.

[Storage System] 

The number of consecutive blocks of protected space in a single user data extent that are mapped to consecutive virtual disk block addresses.

In principle, each user data extent that is part of a virtual disk may have a different user data extent stripe depth. User data extent stripe depth may differ from the redundancy group stripe depth of the protected space extent in which it resides.

[Management]  [Data Security] 

A unique number that identifies an individual to a computer system.

UIDs are the result of authentication processes that use account names, passwords and possibly other data to verify that a user is actually who she represents herself to be. UIDs are input to authorization processes that grant or deny access to resources based on the identification of the requesting user.

[General] 

An encoding for multi-byte character schemes such as Unicode, in which ASCII text encodes to itself and POSIX string manipulation routines work largely as expected.

A 16-bit Unicode string that encodes ASCII text will have every other data byte within it set to zero. The UTF-8 encoding of this text will have a zero only at the end.