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    Types: TextFile
    Names: »a-build-3.tex«

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TextFile

% -*- LaTeX -*-		(really SLiTeX)

\f

\begin{bwslide}
\ctitle	{DYNAMIC FACILITIES}\bf

\begin{nrtc}
\item	RUN-TIME ENVIRONMENT

\item	INITIATORS TEMPLATE

\item	RESPONDERS TEMPLATE

\item	DEFINING A NEW SERVICE
\end{nrtc}
\end{bwslide}


%\f

\begin{note}\em
%this part of the presentation corresponds to part~iv along with section~3.1
%of The Applications Cookbook
%\end{note}


\f

\begin{bwslide}
\ctitle	{DYNAMIC FACILITIES\\ OVERVIEW}

\vskip.15in
\diagram[p]{figureA-49}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{RUN-TIME ENVIRONMENT}

\begin{nrtc}
\item	RUN-TIME ENVIRONMENT RESPONSIBLE FOR ``CIVILIZING'' REMOTE OPERATIONS
	SERVICE

\item	IMPORTANT TRADE-OFF:
    \begin{nrtc}
    \item	FLEXIBILITY FOR SIMPLICITY
    \end{nrtc}

%\item	IN \emph{THE COOKBOOK}, \verb"ROSYLIB" IMPLEMENTS THE RUN-TIME
%	ENVIRONMENT
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{DATA STRUCTURES}

\begin{nrtc}
\item	STUB GENERATOR PRODUCES OPERATION TABLES AS WELL

\item	FOR EACH OPERATION, A TABLE IS DEFINED CONTAINING:
    \begin{nrtc}
    \item	NAME AND NUMBER OF OPERATION

    \item	ARGUMENT ENCODE/DECODE ROUTINES

    \item	RESULT ENCODE/DECODE/FREE ROUTINES

    \item	ERROR TABLE
    \end{nrtc}
\end{nrtc}\small

\begin{verbatim}
    ...

                                        /* OPERATION m-ConfirmedEventReport */
    "m-ConfirmedEventReport", operation_CMIP_m__ConfirmedEventReport,
        encode_CMIP_m__ConfirmedEventReport_argument,
        decode_CMIP_m__ConfirmedEventReport_argument,
        1, encode_CMIP_m__ConfirmedEventReport_result,
           decode_CMIP_m__ConfirmedEventReport_result,
           free_CMIP_m__ConfirmedEventReport_result,
        errors_CMIP_m__ConfirmedEventReport,

    ...
\end{verbatim}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{DATA STRUCTURES (cont.)}

\begin{nrtc}
\item	FOR EACH ERROR, A TABLE IS DEFINED CONTAINING:
    \begin{nrtc}
    \item	NAME AND NUMBER OF ERROR

    \item	PARAMETER ENCODE/DECODE/FREE ROUTINES
    \end{nrtc}
\end{nrtc}\small

\begin{verbatim}
    ...

                                        /* ERROR noSuchObject */
    "noSuchObject", error_CMIP_noSuchObject,
        encode_CMIP_noSuchObject_parameter,
        decode_CMIP_noSuchObject_parameter,
        free_CMIP_noSuchObject_parameter,

    ...
\end{verbatim}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{A TABLE-DRIVEN APPROACH}

\begin{nrtc}
\item	RUN-TIME ENVIRONMENT SHOULD BE GENERALIZED TO WORK WITH THE LARGEST
	POSSIBLE SET OF APPLICATIONS USING REMOTE OPERATIONS

\item	A TABLE-DRIVEN APPROACH PERMITS US TO DECOUPLE OPERATION-SPECIFIC
	INFORMATION
    \begin{nrtc}
    \item	WHAT ARGUMENTS REPRESENTED, HOW THEY ARE ENCODED, etc.
    \end{nrtc}
	FROM OPERATION-GENERIC INFORMATION
    \begin{nrtc}
    \item	THE OPERATION TAKES ARGUMENTS WHICH MUST BE ENCODED, etc.
    \end{nrtc}
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{STUBS REVISITED}

\begin{nrtc}
%\item	STUBS DEFINED BY ROSY CALL EITHER THE \verb"RyOperation" OR THE
%	\verb"RyStub" ROUTINE
%
\item	GENERALLY YOUR STUB ROUTINES WILL USE ``POLICY'' ROUTINES, MAINTAING:
	\begin{nrtc}
	\item	INVOCATION IDENTIFIERS
	\item	LINKED--INVOCATION IDs
	\end{nrtc}
%\item	THE \verb"RyStub" ROUTINE IMPLEMENTS A LESS RESTRICTIVE POLICY:
%    \begin{nrtc}
%    \item	USER SELECTS OPERATION CLASS AND INVOCATION IDENTIFIER
%    \end{nrtc}
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{ASYNCHRONOUS STUBS}

\begin{nrtc}
\item	RECALL
{\small
\begin{verbatim}
#define stub_CMIP_m__ConfirmedEventReport(sd,id,in,rfx,efx,class,roi) \
RyStub ((sd), table_CMIP_Operations, \
        operation_CMIP_m__ConfirmedEventReport, (id), \
        (caddr_t) (in), (rfx), (efx), (class), (roi))
\end{verbatim}}

\item	THE MEANING OF THE PARAMETERS:
    \begin{nrtc}
    \item	\verb"sd": ASSOCIATION-DESCRIPTOR

    \item	\verb"id": INVOCATION IDENTIFIER

    \item	\verb"in": ARGUMENT FOR OPERATION

    \item	\verb"rfx": DISPATCH ROUTINE FOR RESULT

    \item	\verb"efx": DISPATCH ROUTINE FOR ERRORS OR REJECTIONS

    \item	\verb"class": (A)SYNCHRONOUS

    \item	\verb"roi": LOCAL SERVICE INTERFACE INFORMATION
    \end{nrtc}
\end{nrtc}
\end{bwslide}


%\f

\begin{bwslide}
%\ctitle	{INSIDE RYSTUB}
%
%\begin{nrtc}
%\item	RUDIMENTARY PARAMETER CHECK
%
%\item	BUILD PRESENTATION ELEMENT FOR ARGUMENT
%
%\item	BUILD \emph{ACTIVATION BLOCK}
%
%\item	ISSUE RO-INVOKE.REQUEST
%
%\item	IF ASYNCHRONOUS, RETURN
%
%\item	LOOP, WAITING FOR ANY RESPONSE:
%    \begin{nrtc}
%    \item	RO-INVOKE.INDICATION:
%	\begin{nrtc}
%	\item	 PUSH ACTIVATION BLOCK FOR DISPATCHING OPERATION
%	\end{nrtc}
%
%    \item	RO-RESULT, ERROR, OR REJECTION.INDICATION:
%	\begin{nrtc}
%	\item	PARSE OPERATION RESULT OR ERROR PARAMETER AND CALL DISPATCH
%		ROUTINE
%\begin{verbatim}
%result = (*fnx) (sd, id, reason, value, roi);
%\end{verbatim}
%
%	\item	IF RESPONSE WAS FOR US, RETURN
%	\end{nrtc}
%    \end{nrtc}
%\end{nrtc}
%\end{bwslide}


\f

\begin{bwslide}
\ctitle	{SYNCHRONOUS STUBS}

\begin{nrtc}
\item	RECALL
\begin{verbatim}
#define op_CMIP_m__ConfirmedEventReport(sd,in,out,rsp,roi) \
RyOperation ((sd), table_CMIP_Operations, \
        operation_CMIP_m__ConfirmedEventReport, \
        (caddr_t) (in), (out), (rsp), (roi))
\end{verbatim}

\item	THE MEANING OF THE PARAMETERS:
    \begin{nrtc}
    \item	\verb"sd": ASSOCIATION-DESCRIPTOR

    \item	\verb"in": ARGUMENT FOR OPERATION

    \item	\verb"out": RESULT FOR OPERATION OR PARAMETER FOR ERROR

    \item	\verb"rsp": TELLS HOW TO INTERPRET \verb"out"

    \item	\verb"roi": REJECTION INFORMATION FOR OPERATION
    \end{nrtc}
\end{nrtc}
\end{bwslide}


%\f

\begin{bwslide}
%\ctitle	{INSIDE RYOPERATION}
%
%\begin{nrtc}
%\item	RUDIMENTARY PARAMETER CHECK
%
%\item	BUILD PRESENTATION ELEMENT FOR ARGUMENT
%
%\item	BUILD \emph{ACTIVATION BLOCK}
%
%\item	ISSUE RO-INVOKE.REQUEST
%
%\item	LOOP, WAITING FOR SOME RESPONSE:
%    \begin{nrtc}
%    \item	RO-INVOKE.INDICATION:
%	\begin{nrtc}
%	\item	 PUSH ACTIVATION BLOCK FOR DISPATCHING OPERATION
%	\end{nrtc}
%
%    \item	RO-RESULT, ERROR, OR REJECTION.INDICATION:
%	\begin{nrtc}
%	\item	IF FOR US: PARSE OPERATION RESULT OR ERROR PARAMETER AND RETURN
%
%	\item	IF NOT FOR US: STUFF INFORMATION INTO CORRESPONDING ACTIVATION
%		BLOCK
%	\end{nrtc}
%    \end{nrtc}
%\end{nrtc}
%\end{bwslide}


\f

\begin{bwslide}
\ctitle	{RESPONDERS}

\begin{nrtc}
\item	REGISTER A DISPATCH ROUTINE FOR EACH OPERATION USING \verb"RyDispatch"
\begin{verbatim}
RyDispatch (sd, ryo, op, fnx, roi)
\end{verbatim}

\item	THE MEANING OF THE PARAMETERS:
    \begin{nrtc}
    \item	\verb"sd": ASSOCIATION-DESCRIPTOR

    \item	\verb"ryo": OPERATION TABLE

    \item	\verb"op": OPERATION NUMBER

    \item	\verb"fnx": DISPATCH ROUTINE

    \item	\verb"roi": FAILURE INDICATOR
    \end{nrtc}
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{OPERATION DISPATCH}

\begin{nrtc}
\item	WHILE WAITING FOR ``SOMETHING TO HAPPEN'', A RO-INVOKE.INDICATION
	CAUSES,

\item	THE PRESENTATION ELEMENT FOR THE OPERATIONS ARGUMENT IS PARSED INTO A STRUCTURE
	AND THE DISPATCH ROUTINE IS CALLED:
%\begin{verbatim}
%result = (*fnx) (sd, ryo, rox, in, roi)    
%\end{verbatim}

\item	DISPATCH ROUTINE HAS THREE OPTIONS
    \begin{nrtc}
    \item	TO RETURN A RESULT

    \item	TO RETURN AN ERROR

    \item	TO REJECT AN OPERATION
    \end{nrtc}
\end{nrtc}
\end{bwslide}


%\f

\begin{bwslide}
%\ctitle	{CLEAN-UP}
%
%\begin{nrtc}
%\item	WHEN AN ASSOCIATION IS ABORTED (e.g., DUE TO NETWORK FAILURE),
%	SOMETHING MUST BE DONE WITH ACTIVATION BLOCKS
%
%\item	IDEALLY, WOULD LIKE TO:
%    \begin{nrtc}
%    \item	RETAIN THIS STATE,
%
%    \item	RE-ESTABLISH THE ASSOCIATION, AND
%
%    \item	CONTINUE WHERE WE LEFT OFF
%    \end{nrtc}
%
%\item	NO SUCH LUCK, ACTIVATION BLOCKS ARE FLUSHED!
%    \begin{nrtc}
%    \item	A LOT OF HARD ISSUES NEED TO BE RESOLVED IN ORDER TO DO THE
%		``RIGHT THING''
%
%    \item	ACTUALLY, FOR ASYNCHRONOUS INVOCATIONS, A REJECTION IS
%		PASSED UP
%    \end{nrtc}
%\end{nrtc}
%\end{bwslide}


\f

\begin{bwslide}
\ctitle	{INSIDE AN INITIATOR}\bf

\begin{nrtc}
\item	ALMOST OF THIS IS ``BOILERPLATE''
\item	WE'LL CONSIDER ONLY THE HIGHLIGHT:
		INVOKING AN OPERATION
\end{nrtc}
\end{bwslide}


%\f

\begin{bwslide}
%\ctitle	{INVOKING AN OPERATION}
%
%\begin{nrtc}
%\item	ALTHOUGH \emph{THE COOKBOOK} TRIED TO MAKE THINGS SIMPLE,
%	CALLING A STUB IS NOT EASY
%\end{nrtc}
%\end{bwslide}


%\f

\begin{bwslide}
%\ctitle	{ASYNCHRONOUS INVOCATION}\small
%
%\hrule\vskip.15in
%\begin{tgrind}
%\let\linebox=\relax
%\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
%\input figureA-54\relax
%\end{tgrind}
%\end{bwslide}
%
%
%\f

\begin{bwslide}
%\ctitle	{ASYNCHRONOUS INVOCATION (cont.)}\small
%
%\hrule\vskip.15in
%\begin{tgrind}
%\let\linebox=\relax
%\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
%\input figureA-55\relax
%\end{tgrind}
%\end{bwslide}
%
%
%\f

\begin{bwslide}
%\ctitle	{ASYNCHRONOUS INVOCATION (cont.)}\small
%
%\hrule\vskip.15in
%\begin{tgrind}
%\let\linebox=\relax
%\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
%\input figureA-56\relax
%\end{tgrind}
%\end{bwslide}
%
%
%\f

\begin{bwslide}
%\ctitle	{ASYNCHRONOUS INVOCATION (cont.)}\small
%
%\hrule\vskip.15in
%\begin{tgrind}
%\let\linebox=\relax
%\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
%\input figureA-57\relax
%\end{tgrind}
%\end{bwslide}


%\f

\begin{bwslide}
%\ctitle	{ASYNCHRONOUS INVOCATION (cont.)}\small
%
%\hrule\vskip.15in
%\begin{tgrind}
%\let\linebox=\relax
%\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
%\input figureA-58\relax
%\end{tgrind}
%\end{bwslide}


%\f

\begin{bwslide}
%\ctitle	{SIMPLIFIED ASYNCHRONOUS INVOCATION}\small
%
%\hrule\vskip.15in
%\begin{tgrind}
%\let\linebox=\relax
%\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
%\input figureA-59\relax
%\end{tgrind}
%\end{bwslide}


\f

\begin{bwslide}
\ctitle	{SYNCHRONOUS INVOCATION}\small

\hrule\vskip.15in
\begin{tgrind}
\let\linebox=\relax
\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
\input figureA-60\relax
\end{tgrind}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{SYNCHRONOUS INVOCATION (cont.)}\small

\hrule\vskip.15in
\begin{tgrind}
\let\linebox=\relax
\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
\input figureA-61\relax
\end{tgrind}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{SYNCHRONOUS INVOCATION (cont.)}\small

\hrule\vskip.15in
\begin{tgrind}
\let\linebox=\relax
\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
\input figureA-62\relax
\end{tgrind}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{INSIDE A RESPONDER}\bf

\begin{nrtc}
\item	AGAIN, A LOT OF THIS WILL BE ``BOILERPLATE''
\item	WE WILL ONLY LOOK AT RESPONDING TO AN OPERATION INVOKATION
\end{nrtc}
\end{bwslide}


%\f

\begin{bwslide}
%\ctitle	{RESPONDING TO AN OPERATION}
%
%\begin{nrtc}
%\item	WHEN AN ACTIVATION BLOCK IS PUSHED,
%	THE DISPATCH ROUTINE IS CALLED
%\end{nrtc}
%\end{bwslide}


\f

\begin{bwslide}
\ctitle	{RESPONDING TO AN OPERATION (cont.)}\small

\hrule\vskip.15in
\begin{tgrind}
\let\linebox=\relax
\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
\input figureA-63\relax
\end{tgrind}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{RESPONDING TO AN OPERATION (cont.)}\small

\hrule\vskip.15in
\begin{tgrind}
\let\linebox=\relax
\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
\input figureA-64\relax
\end{tgrind}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{RESPONDING TO AN OPERATION (cont.)}\small

\hrule\vskip.15in
\begin{tgrind}
\let\linebox=\relax
\def\_{\ifstring{\char'137}\else\underline{\ }\fi}
\input figureA-65\relax
\end{tgrind}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{DEFINING A NEW SERVICE}\bf

\begin{nrtc}
\item	FINALLY, NEED TO IDENTIFY THE APPLICATION TO THE NETWORK

\item	THINGS TO BE DEFINED:
    \begin{nrtc}
    \item	ABSTRACT SYNTAX

    \item	APPLICATION CONTEXT NAME

    \item	APPLICATION ENTITY TITLE

    \item	PRESENTATION ADDRESS

    \item	LOCAL PROGRAM
    \end{nrtc}
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{ABSTRACT SYNTAX}

\begin{nrtc}
\item	DESCRIBES THE DATA STRUCTURES BEING EXCHANGED BY THE SERVICE

\item	\begin{verbatim} "ips-osi-mips cmip pci"    1.0.9596.2.1.1 \end{verbatim}
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{APPLICATION CONTEXT NAME}

\begin{nrtc}
\item	DESCRIBES THE ELEMENTS AND PROTOCOL BEING USED BY THE SERVICE

\item	\begin{verbatim} "iso cmip"    1.0.9596.2.2.1 \end{verbatim}
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle {APPLICATION ENTITY TITLE}

\begin{nrtc}
\item	UNIQUELY NAMES AN ENTITY IN THE NETWORK
\item	VALUE IS A DISTINGUISHED NAME, e.g.,
\begin{quote}\small\begin{verbatim}
	c=US@o=TWG@ou=Software Engineering@cn=boomer@cn=filestore
	\end{verbatim}\end{quote}
	(THIS IS A STRING REPRESENTATION OF A COMPLEX ASN.1 TYPE!)
\item	SIMPLER APPROACH IS TO USE LOCAL ALIASING (``boomer-filestore'') PRIOR TO
	RESOLUTION:
	\begin{nrtc}
	\item	LHS (QUALIFIER) MAPS TO INITIAL PART OF DISTINGUISHED NAME
	\item	RHS (DESIGNATOR) MAPS TO SUFFIX
	\end{nrtc}
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle {APPLICATION ENTITY TITLE}

\begin{nrtc}
\item	FOR INITIATORS, THE DIRECTORY IS ASKED TO RETURN THE ``PRESENTATION ADDRESS''
	ATTRIBUTE OF THIS OBJECT
\item	CONCEPTUALLY, RESPONDERS STORE THIS INFORMATION IN THE DIRECTORY
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle {DYNAMIC CHARACTERISTICS: \\ PRESENTATION ADDRESS}

\begin{nrtc}
\item	UNIQUELY IDENTIFIES THE LOCATION OF AN ENTITY
\item	VALUE IS
	\begin{nrtc}
	\item	PRESENTATION SELECTOR (0+ OCTETS)
	\item	SESSION SELECTOR (0+ OCTETS)
	\item	TRANSPORT SELECTOR (0+ OCTETS)
	\item	NETWORK ADDRESSES (AT LEAST 1)
	\end{nrtc}
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle {LOCAL ENVIRONMENT: \\ CURRENT METHOD}

\begin{nrtc}
\item	TRANSPORT LISTENER RESIDES ON EACH END-SYSTEM
\item	FOR EACH SERVICE LISTED IN LOCAL DATABASE
	\begin{nrtc}
	\item	LISTEN ON ASSOCIATED TRANSPORT ADDRESS
	\item	UPON RECEIVING AN INCOMING CONNECTION, TSAPD
		INVOKES ASSOCIATED PROGRAM
	\end{nrtc}
\item	PROGRAM IS CALLED A DYNAMIC RESPONDER
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle {LOCAL ENVIRONMENT: \\ CURRENT METHOD (cont.)}

\begin{nrtc}
\item	SOME RESPONDERS MAY WISH TO SERVICE MULTIPLE INITIATORS
\item	DIFFERENT APPROACH:
	\begin{nrtc}
	\item	SERVICE NOT LISTED IN LOCAL DATABASE
	\item	PROGRAM LISTENS ON OWN TRANSPORT ADDRESS
	\end{nrtc}
\item	PROGRAM IS CALLED A STATIC RESPONDER
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle {LOCAL ENVIRONMENT: \\ FUTURE METHOD}

\begin{nrtc}
\item	LOCAL DATABASE CONTAINS
	\begin{nrtc}
	\item	SERVICE NAME
	\item	LOCAL PROGRAM
	\end{nrtc}
	\begin{verbatim} "tsap/cmip"    #519    /usr/etc/ros.cmip args...  \end{verbatim}
	BUT NOT TRANSPORT ADDRESS
\item	FOR EACH SERVICE
	\begin{nrtc}
	\item	TRANSPORT LISTENER LISTENS ON RANDOM TRANSPORT ADDRESS
	\item	LISTENER REGISTERS SERVICE \& TRANSPORT ADDRESS WITH THE DIRECTORY
	\end{nrtc}
\item	SIMILAR APPROACH IS USED BY STATIC RESPONDERS
\end{nrtc}
\end{bwslide}


\f

\begin{bwslide}
\ctitle	{DYNAMIC FACILITIES:\\ REVIEW}

\vskip.15in
\diagram[p]{figureA-49}
\end{bwslide}


\f

\begin{bwslide}
\ctitle {CLOSING COMMENTS\\UPPER--LAYER ADDRESSING}

\begin{nrtc}
\item	TOO MUCH FREEDOM
\item	DYNAMIC RESPONDER PREFER TO ``DISPATCH'' ON TRANSPORT SELECTOR
\item	STATIC RESPONDERS MAY REQUIRE A UNIQUE NETWORK ADDRESS
\end{nrtc}
\end{bwslide}


\begin{bwslide}
\ctitle {UPPER--LAYER ADDRESSING}

\begin{nrtc}
\item	U.S. GOSIP CALLS FOR DISPATCHING ON PRESENTATION SELECTOR
\item	OKAY FOR DYNAMIC RESPONDERS
\item	STATIC RESPONDERS MAY STILL REQUIRE A UNIQUE NETWORK ADDRESS
	\begin{nrtc}
	\item	WITH REAL OSI NETWORK SERVICE, STATIC RESPONDERS CAN DISPATCH
		ON TRANSPORT SELECTOR
	\end{nrtc}
\end{nrtc}
\end{bwslide}