Fw: [mqtt-comment] MQTT protocol

Hi Georges, 

Thanks for your question on MQTT as
part of the v3.1.1 Committee Specification Draft public review.

Andrew Banks - one of the Technical Committee's editors - has taken a look
into this and provided the response below.

Best regards

Richard

Richard Coppen CEng
FBCS
 IBM United Kingdom

Software Engineer
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WebSphere MQ
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blog:
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Georges, 

Many thanks for your feedback on the CSD. 

I've been looking into this, I think the relevant section in the specification
is: 

1.1        Handling protocol violations

If the Client or Server encounters a transient error while processing an
inbound Control Packet it MUST close the Network Connection on which it
received that packet [MQTT-4.8.0-1]. If a Server detects a transient error
it SHOULD NOT disconnect or have any other affect on its interactions with
any other Client. 

So we are saying that only the client
causing the problem must be disconnected, all other clients will remain
connected, the server continues to listen on its port. A future version
of the protocol could extend this so that negative outcomes are sent back
to the client. 

I hope this addresses your concern. If
you have any other questions please add a comment to the mailing list 

Andrew Banks

Telephone (44) 1962 816123 

----- Forwarded by Andrew
Banks/UK/IBM on 05/02/2014 16:35 ----- 

From:        Luel
Georges <> 

To:        ""
<>, 

Date:        03/02/2014
09:33 

Subject:        [mqtt-comment]
MQTT protocol 

Sent by:        <>

Hi, 

  

I am a project manager and SCADA architect for the STIB in Belgium.

  

It is the company who manage all the people transportation for Brussels.

  

That means 1500 vehicles and more than 7000 people.

  

I have a comment about the new MQTT protocol. 

  

I think it is not a good idea to close the port in case of transmission
errors. 

  

I think that the protocol must be robust and throw wrong message.

  

Best regards 

  

  

  

 

  

  
Georges
Luel 

Project Manager 

InfoTech - Projects IT P - SIC P 

Information Systems 

Transport Systems 

STIB-MIVB - rue Royale 76 Koningsstraat - Bruxelles 1000 Brussel

Tel: +32 2 563 80 58 - GSM: +32 499 866 549 

E-mail: 
- Web: www.stib.be
– www.mivb.be

  

  

 

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