Re: [core] #397 (coap-tcp-tls): CON usage with CoAP over TCP

"weigengyu" <> Tue, 12 April 2016 05:37 UTC

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Date: Tue, 12 Apr 2016 13:37:28 +0800
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Subject: Re: [core] #397 (coap-tcp-tls): CON usage with CoAP over TCP
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The same situation is when a CON message goes through a C2C proxy.
If that C2C proxy has one port with CoAP over UDP and one port with CoAP 
over TCP,
the COM MSG should be converted to NON MSG by the current draft.


Gengyu WEI
Network Technology Center
School of Computer
Beijing University of Posts and Telecommunications
From: core issue tracker
Sent: Tuesday, April 05, 2016 9:46 AM
To: ;
Subject: [core] #397 (coap-tcp-tls): CON usage with CoAP over TCP

#397: CON usage with CoAP over TCP

In Timothy


In section 4 Message Format says:

The ’Message Length’ field is a 16-bit unsigned integer in network byte
order. It provides the length of the subsequent CoAP message (including
the CoAP header but excluding this message length field) in bytes (so its
minimum value is 2). The Message ID and message type are meaningless and
thus elided (what would have been the message type field is always filled
with what would be the code for NON (01)).

What would happen if an Application where to place a CON in the message
type field. Based on my reading of this text I would expect the message
type from the  application to be ignored and the transport to put in a NON
message. Is that correct?

Reporter:                           |      Owner:  draft-ietf-core-coap-          |
     Type:  protocol defect          |     Status:  new
Priority:  major                    |  Milestone:
Component:  coap-tcp-tls             |    Version:
Severity:  Active WG Document       |   Keywords:

Ticket URL: <>
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