[ebxml-msg] Comments on the 1.09 about ConversationId

[SHIMAMURA Masayoshi <shima.masa@jp.fujitsu.com>]

The specification of ConversationId element on page 20 has two problems:

1) The value of the ConversationId element is determined by the Party.
   
   ConversationId is very important for guarantee of message order.
   Because message order is guaranteed per each conversation. Thus MSH
   instead of Party should determines and manages the value of the
   ConversationId to prevent invalid ConversationId value. I propose
   following change:
   
   Line 823-825
     ... The Party initiating a conversation determines the value of the
     ConversationId element that SHALL be reflected in all messages
     pertaining to that conversation.
        |
        V
     ... The Party indicates start and end of conversation to MSH. The
     value of the ConversationId element is generated and managed by the
     MSH.

2) Receiving MSH can't know the end of conversation.
   
   Receiving MSH holds received conversation's ConversationId in its
   persistent storage for guarantee of message order. However receiving
   MSH has not any way to know the end of conversation. Thus receiving
   MSH don't know when ConversationId's information can be removed from
   its persistent storage.
   
   To resolve the problem, I propose to add status attribute to
   ConversationId element. The status attribute takes one of following
   three values:
       Start:  First message in messages belong with the conversation.
       Middle: A message except for first and last message in messages
               belong with the conversation.
       End:    Last message in messages belong with the conversation.
       Alone:  First and last message in the conversation which consist
               of only one message. It MUST be specified when the
               conversation have only one message.


Regards, 

--
SHIMAMURA Masayoshi <shima.masa@jp.fujitsu.com>
TEL:+81-45-476-4590(ext.7128-4241)  FAX:+81-45-476-4726(ext.7128-6783)
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