Subject: Re: [core] My endpoint has two addresses

From: Mert Ocak <[email-masked]>
Date: Mon, 30 Oct 2017 13:33:46 +0000

Hi Christian,

The issue Jim raised was not covered with protocol-negotiation draft indeed in the version we discussed in Prague. That version proposed a way to expose alternative transports on a per-server basis. However, in the new version of the draft for Singapore, we are introducing a new link attribute "ol" : other locations, in which the CoAP server can expose the same resource on different locations/transports. The new attribute works as a per resource basis and can be used both on RD or on /.well-known/core. This way enables exposing resources both per-server or per-resource on the same server, something we had several discussions about in Prague. The new attribute also prevents overloading the meaning of "con", since the original idea of "con" was not intended for per-resource.

This approach can be used for exposing the same resource on different raw addresses as in the Jim's issue since we are not restricting the use of "ol" for just different transports. 

Cheers,
Mert

On 21/09/2017, 15.01, "Christian Amsüss" <[email-masked]> wrote:

    Hello Jim,
    Hello Bill and Mert,
    
    On Fri, Sep 08, 2017 at 09:28:41AM +0200, peter van der Stok wrote:
    > For the moment, we made the model such that and extension to multiple
    > contexts is possible, but not yet supported by the RD, given that all these
    > extensions are still under discussion,
    
    More concretely, this is where I hope that
    core-coap-protocol-negotiation will take over. We're deliberately
    keeping multiple-base-addresses out of resource-directory (an earlier
    state already allowed more than one address) so this can be
    comprehensively specified there based on model that contains only the
    extension point for it.
    
    Bill and Mert, Jim the issue Jim raised is not fully covered by the
    protocol-negotiation draft or what we talked about in Prague, but
    involves the choice of an Internet layer when raw addresses are used.
    Will we be able to use the mechanisms introduced there in the absence of
    hostnames for an IPv4 and an IPv6 addresses (or multiple IPv6
    addresses)?
    
    Best regards
    Christian
    
    -- 
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