Re: SequenceNumber [was:minutes 21-Dec-2000 tr&p con-call]

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

Mr. David Burdett, 

I think guarantee of message order is *one of QoS*. If so, it should be
specified clearly in the ReliableMessagingInfo element. So I suggested
alternative 1. In functional viewpoint, there is not difference between
alternative 1 and 2. But I believe that the alternative 1 is clearer and
better specification.

On Thu, 04 Jan 2001 23:47:03 -0800
"Burdett, David" <david.burdett@commerceone.com> wrote:
> Shimamura
> 
> I think that our thoughts are beginning to converge. I agree that making
> sequence number unique within conversation id makes sense.
> 
> I have also read your paper, and think that we have two alternatives:
> 1. Your alternative where we have a separate messageOrderSemantics that
> indicates that the sequence of arrival of messages within the conversation
> MUST be preserved by a recipient.
> 2. Use the existence of the sequence number to imply that sequence must be
> preserved. This would mean that the first message in a conversation would
> have to have a sequence number and the omission of a sequence number later
> would be an error. Similarly the presence of a sequence number when there
> wasn't one on the first would also be an error.
> 
> I do think though that if we do have messageOrderSemantics.
> 
> I am also wondering if we need to worry about overflow if sequence number is
> going to be unique with Conversation Id. For example, if sequence has a
> maximum value of 99,999,999 then effectively a conversation with a 100
> million messages would, I think, in practice never occur.
> 
> Thoughts?
> 
> David

Regards, 

--
SHIMAMURA Masayoshi <shima.masa@jp.fujitsu.com>
TEL:+81-45-476-4590(ext.7128-4241)  FAX:+81-45-476-4726(ext.7128-6783)
Planning Dep., Strategic Planning Div., Software Group, FUJITSU LIMITED