Subject: Basic Conversation and OSI TP

From: "John E. Fetvedt (919-254-4366)" <[email-masked]>
Date: Wed, 9 Mar 94 08:55:51 EST

Peter,

     The answer is that the implementation sends the contents of the
user buffer using as many UD-TRANSFER-requests as it needs. To the lower
layers the LLs are just part of the user's data and no special
significance can be assigned to them. However, being as this whole
process is not seen by the CPI-C user, I'm not sure that any change is
needed to the CPI-C document.

     Cheers.

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Date: Tue, 8 Mar 94 12:21:49  +0100
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Basic Conversation and OSI TP

We detected an unclear intem in the CPI-C 2.0 document
concering Basic Conversation and OSI TP.

If a program uses basic conversation a buffer sended by Send_Data
may typically have the following structure:

  +--+------------+--+-----------------+
  !LL! Text       !LL! Text            !
  +--+------------+--+-----------------+

A program sends this buffer using Send_Data (..., buffer, send_length, ...)
where
	buffer          is the address of the buffer
	send_length     is the lenght of the buffer

If we want to implement basic conversation with OSI TP there are
2 possibilities:

1  The CRM sends this buffer using one UD-TRANSFER-request.
   The LL fields are carried as part of the octet string.

2  The CRM sends this buffer using two UD-TRANSFER-requests.
   The LL fields are mapped to the length parameter of the
   UD-TRANSFER-request.

The CPI-C 2.0 document has to describe which implementation is the
true one. Otherwise it may happen, that CPI-C programs using Libraries
from different companies cannot work together.

Regards
Peter Binninger

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Peter Binninger                         Voice: (+49) 7531-87-4758
Computer Gesellschaft Konstanz mbH      Fax:   (+49) 7531-87-4888
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