SDL-News: Servicing Multi-state rpcs

Subject: SDL-News: Servicing Multi-state rpcs
From: Piyush Gupta (
Date: Sat May 15 1999 - 14:26:45 GMT

The originator of this message is responsible for its content.
-----From Piyush Gupta <> to sdlnews -----

The following question is about how remote procedures with
multiple states are serviced according to SDL92 semantics :

If a remote procedure is not occuring in save or as input in
some transition from a state in process transition diagram,
then there exists an implicit transition for it for this state
(as in Z.100).

Does this hold true for all the states i.e. not only for the
states defined in the process graph but also for the states of
all the local/exported procedures ?

Consider the following example :-

In a process-state s, I receive a remote procedure call for rpc1.
rpc1 is now executed while the current state remains s.
Suppose rpc1 waits for signal sig1 in some state rs1, then
remote procedure call for rpc2 arrives in the input queue.

There are 2 alternatives :
1. rpc2 is serviced while remaining in state rs1
2. rpc2 is serviced after rpc1 completes its execution.

It is not clear from the standard that which of the two
alternatives is correct ?


Piyush Gupta

-----End text from Piyush Gupta <> to sdlnews -----
Join for extra SDL Forum Society benefits
For help, email "" with the body of your email as:
or (iff this does not answer your question) email:

This archive was generated by hypermail 2a23 : Sun Jun 16 2013 - 10:41:40 GMT