Re: [core] Fwd: New Version Notification for draft-silverajan-core-coap-protocol-negotiation-04.txt

[Christian Amsüss <[e-mail]>]

Hi Bill,

thanks for your response.

On Tue, Nov 15, 2016 at 06:26:54PM +0200, Bill Silverajan wrote:
> I think this is a very interesting point when it comes to using CoAP over
> reliable transports such as TCP and WebSockets with the RD. While UDP
> sockets allow reuse and peer-to-peer communication, the same cannot be said
> for the others. i.e. if you're registering with a reliable transport
> protocol, I assume you must use "con", since the endpoint would use a
> different location (or a system generated client random port number in
> userspace) than the CoAP server endpoint.

You are right about the port number, I didn't think of that. I'll go
through the RD and TCP drafts again to check whether this needs further
notes.

> One thing: The CoAP URI for (secure) WebSockets as defined in core-tcp-tls
> does not specify a path component for the Websocket endpoint. It was too
> tricky to do location/identification by separating the path components for
> the websoocket endpoint away from the CoAP resource. However, this problem
> is addressed in this draft.

Indeed; then the example in 4.2 needs updating to drop the /ws/, doesn't
it? (I suppose that it is neither to mean that clients should connect
their web-sockets to ws://.../ws/ instead of .well-known/core, nor that
they should prefix /sensors/temp into /ws/sensors/temp when sending a
request to the WS).

> So technically all four lookup types (including d and gp)

I'm looking forward to seeing the gp applications you mentioned in the
presentations.

> "tt" can be used to look up a specific transport type (or * for all). I'm
> not sure if it needs a default value?

The default value would describe what protocol-negotiation-unaware
clients would receive, I think this does deserve mention.

Best regards
Christian

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