Instruction Manual

Software Identification (SWID) User’s Guide—527243-004
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1 SWID Overview
The Software Identification (SWID) utility aims to uniquely identify and verify the
integrity of NonStop system files. SWID is available as a stand-alone utility.
SWID uniquely identifies all NonStop system files distributed by HP. This unique
identifier is known as the fingerprint of the file and is used to perform software
inventory, version analysis, and delivery.
SWID supersedes the Version Procedure (VPROC) utility (T9617), which was used for
software identification.
What is Fingerprinting?
The phrase “fingerprint of a file” means a context-free and content-dependent attribute
of a file that can be computed by reading the contents of the file such that:
•
Two identical copies of a file must yield the same fingerprint regardless of the
context (for example, file name, location, ownership, creation time, and last-
modified time).
•
Two files with different contents should not yield the same fingerprint.
A fingerprint is displayed as a character string of fixed length (16 hex characters).
Internally, a fingerprint is stored as a 96-bit number of which 32 bits are used for
product version and other reserved information, and the other 64 bits are used to store
the fingerprint string. SWID reports two types of fingerprints: current and original.
The unique fingerprint generated by SWID can form a basis for change management
by other software products.
Available Fingerprints
Current, composite, and original fingerprints are discussed here with a definition and
explanation as to how they are generated.
Current Fingerprint
The normal fingerprint format is known as the current fingerprint and is computed by
reading the current contents of a file. SWID can compute the current fingerprint of any
Enscribe file. The current fingerprint of a file changes if its contents change. Only the
portions of a file that do not change during its lifecycle are used for computing the
fingerprint. For example, the portion of an object file that changes when the file is run
(during Guardian Fixup) is not used for computing the fingerprint of the object file.
Composite Fingerprint
A composite fingerprint is a fingerprint of all files within a given file set. SWID can
compute a composite fingerprint of a single file set or multiple file sets by reading the