Browse Prior Art Database

Parsing Querying Specification for Architected Encodings

IP.com Disclosure Number: IPCOM000109501D
Original Publication Date: 1992-Sep-01
Included in the Prior Art Database: 2005-Mar-24
Document File: 3 page(s) / 149K

Publishing Venue

IBM

Related People

Fitzgerald, AK: AUTHOR [+2]

Abstract

A language element is disclosed that enables users to specify queries against data structures which conform to containment rules. This language element or syntax can be applied to any data encoding which conforms to these rules, which include many of the Systems Network Architecture (SNA) formats.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Parsing Querying Specification for Architected Encodings

       A language element is disclosed that enables users to
specify queries against data structures which conform to containment
rules.  This language element or syntax can be applied to any data
encoding which conforms to these rules, which include many of the
Systems Network Architecture (SNA) formats.

      The importance of this method of specification is its
application to many kinds of commonly implemented data structures.  A
few examples are SNA Alerts, Link Events, and Statistics.  The
language element described here is not sensitive to what the specific
data structure is or whether its architecture is later enhanced, as
long as it obeys containment rules.

      An encoding conforms to the containment rules and is supported
by this syntax if it is a "nesting" of structures which start with a
length/key pair, and contains "data" only at the lowest levels.  In
SNA, 2-byte (LLLLKKKK) structures are called GDS-variables or major-
vectors, and 1-byte (LLKK) structures are called subvectors or
subfields.

      A simplified example of a conforming encoding is shown in the
figure (each 2 characters represents one byte).  The particular keys
(or IDs) and data are not important.

      In the figure, 1212 is the highest-level key.  It contains two
1326s, which are defined to contain 1-byte length/key structures.
Each 1326 contains one 01 and two 02s.  Data is contained in the
lowest level structures (01 and 02).

      An implementation of this language element has been done in
NetView* V2R2, in its automation table (AT) language, and is
described below.  NetView permits users to create an automation
specification by combining statements of the following form in a
file:
      IF F L D THEN A;     where:
           F is a function name (including various parameters),
           L is the logical operator "=" or "^=",
           D is a data description,
             is an action set which is executed if "F L D" evaluates
"true".

      The language element fits in as a "function name" as described
above.  Since the kinds of SNA encodings that may be automated by
NetView are called Management Service Units (MSUs) and the idea is to
query a segment of an MSU, the function-name associated with this
implementation is MSUSEG. Syntax follows:
      If MSUSEG (loc byte bit) L D, where
           loc (location, which is required) = ID(o).ID(o)....
           ID = 2 or 4 character representation of 1 or 2 byte ID (or
key).  The first is required.  The second thru nth levels are
optional.
           .  = contains (i.e., the ID on the left contains the ID on
the right).
           o  = occurrence number, counting from 1.  "*" is a special
occurrence number which means "any".  Optional at every level,
default = 1.
         byte = the by...