HLA Evolved: IEEE 1516 HLA Framework and Rules

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HLA Evolved IEEE 1516 HLA Framework and Rules

• Tiger Team Out-Brief
• DG Meeting Sep 05
• Fall SIW - Orlando

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IEEE 1516 HLA Framework RulesComment 9 (Round
1 Carryover)
Comment Description By the current definition,
an object class may be published if an attribute
from a superclass is published. For example,
consider a FOM that contains an object class
"Platform" with attribute "Position" a subclass
of "Platform" called "Aircraft" with attribute
"Velocity" and a subclass of "Aircraft" called
"Sopwith" with attribute "PropSpeed". If a
joined federate publishes the "Position"
attribute of the "Aircraft" class, by the current
definition "Platform" and "Sopwith" are also
published object classes from the perspective of
that joined federate Suggested Resolution from
Commenter Specify that the object class must
also be an argument to the "Publish Object Class
Attributes" call. PDG Round 1 Resolution PDG
Round 1 Resolution Code HR. PDG actions DG
editor to modify the commenters proposed
solution to be correct and revise the rules
accordingly. PDG Round 2 Resolution PDG Round
2 Resolution Code HTT. A Tiger Team was formed
to bring back suggested resolution.
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IEEE 1516 HLA Framework RulesComment 9 (Round
1 Carryover)

• Tiger Team Members Mikael Karlson, Reed Little,
  Doug Wood, and Roger Wuerfel
• Proposes to accept comment 9 with a minor change
  (A2) and accept comment 12 with an alternative
  resolution (A3). 
• The definition for "published" was revised to
  clarify that the class must also be an argument
  in the publish object class attributes service
  invocation. 
• The definition for subscribe does not need to be
  revised because it contains a phrase that
  clarifies it indirectly.
• However, a review of the occurrences of these two
  words in the specification identified an
  ambiguity in the use of the word published and
  another with the use of the word subscribed.
  Both of the clauses uses "published" and
  "subscribed" pertaining to a class and pertaining
  to attributes without connecting the two
  together.
• The resulting ambiguity could lead the reader to
  believe that a class is published/subscribed if
  any of its attributes are published/subscribed at
  any other class where those attributes are also
  available.
• The review also identified a cut-and-paste typo
  where "published" was used instead of
  "subscribed" in the MOM OMT definition table 15
  for the definition of HLArequestSubscriptions.

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IEEE 1516 HLA Framework RulesComment 9 (Round
1 Carryover)
Tiger Team Suggested Resolution  A2 Add the text
"along with the object class" to the definition
and revise clause 5.1.2.i  by using the phrase
"published attributes of that class" to connect
the attribute publication to the object class.
Also correct a cut-and-paste typo where
"published" was used instead of "subscribed" in
the MOM OMT definition table 15 for the
definition of HLArequestSubscriptions. 3.1.66 (a)
Old Pertaining to an object class such that,
from the perspective of a given joined federate,
there is at least one available attribute of the
object class that was an argument to a Publish
Object Class Attributes service invocation that
was not subsequently unpublished via the
Unpublish Object Class Attributes service. 3.1.66
(a) New Pertaining to an object class such
that, from the perspective of a given joined
federate, there is at least one available
attribute of the object class that was an
argument along with the object class to a Publish
Object Class Attributes service invocation that
was not subsequently unpublished via the
Unpublish Object Class Attributes service.
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IEEE 1516 HLA Framework RulesComment 9 (Round
1 Carryover)
5.1.2.i Old From a joined federate's
perspective, an object class shall be published
if and only if at least one attribute of the
object class is published by the joined
federate.   5.1.2.i New From a joined federate's
perspective, an object class shall be published
if and only if the joined federate has published
attributes of that object class.
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IEEE 1516 HLA Framework RulesComment 12
(Round 1 Carryover)
Comment Description This is similar to the
comment about subclasses and superclasses of a
published object class, but for the term
"subscribed" instead. If a joined federate
subscribes to an attribute of a given level of
object class, are that object class' superclasses
(up to the class at which the attribute is
defined) and subclasses also subscribed object
classes? Suggested Resolution from Commenter
Probably specify that the object class must also
be an argument of the call to the function to
subscribe to the attribute. PDG Round 1
Suggested Resolution PDG Round 1 Resolution
Code HR. There is some question about which
definition this comment is against there may be
a content problem as a result of IEEE editor
changes PDG actions the DG editor to inspect the
text in 3.1.93 and 3.1.94 for correctness against
the I/F Spec and develop a proposed solution.
PDG Round 2 Suggested Resolution PDG Round 2
Resolution Code HTT. A Tiger Team was formed to
bring back suggested resolution.
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IEEE 1516 HLA Framework RulesComment 12
(Round 1 Carryover)

• Tiger Team Suggested Resolution A3
• The definition of subscribed in clause 3.1.93
  includes the phrase "subscribed attributes of
  that object class" that is a derivation of the
  phrase "subscribed attributes of an object
  class".
• The later phrase is included in the definitions
  and it associates the class and attributes with
  the same subscribe object class attributes
  service invocation. 
• While the connection to the object class may not
  be directly stated, the ambiguity present in
  definition 3.1.66 does not exist in definition
  3.1.93.  However, the use of "subscribed" in
  clause 5.1.2.h does contain a similar ambiguity
  and it is revised as follows.
• It can be corrected by using the same phrase
  "subscribed attributes of that class." Revise
  the text to connect the attribute subscription to
  the object class.

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IEEE 1516 HLA Framework RulesComment 12
(Round 1 Carryover)
5.1.2.h Old From a joined federates
perspective, an object class shall be subscribed
if and only if the joined federate is subscribed
to at least one available attribute of the object
class.   5.1.2.h New From a joined federates
perspective, an object class shall be subscribed
if and only if the joined federate has subscribed
attributes of that object class.