Subject: [core] I-D Action: draft-ietf-core-resource-directory-07.txt

From: [email-masked]
Date: Mon, 21 Mar 2016 16:34:47 -0700

A New Internet-Draft is available from the on-line Internet-Drafts directories.
This draft is a work item of the Constrained RESTful Environments of the IETF.

        Title           : CoRE Resource Directory
        Authors         : Zach Shelby
                          Michael Koster
                          Carsten Bormann
                          Peter van der Stok
	Filename        : draft-ietf-core-resource-directory-07.txt
	Pages           : 55
	Date            : 2016-03-21

Abstract:
   In many M2M applications, direct discovery of resources is not
   practical due to sleeping nodes, disperse networks, or networks where
   multicast traffic is inefficient.  These problems can be solved by
   employing an entity called a Resource Directory (RD), which hosts
   descriptions of resources held on other servers, allowing lookups to
   be performed for those resources.  This document specifies the web
   interfaces that a Resource Directory supports in order for web
   servers to discover the RD and to register, maintain, lookup and
   remove resources descriptions.  Furthermore, new link attributes
   useful in conjunction with an RD are defined.

The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-ietf-core-resource-directory/

There's also a htmlized version available at:
https://tools.ietf.org/html/draft-ietf-core-resource-directory-07

A diff from the previous version is available at:
https://www.ietf.org/rfcdiff?url2=draft-ietf-core-resource-directory-07

Please note that it may take a couple of minutes from the time of submission
until the htmlized version and diff are available at tools.ietf.org.

Internet-Drafts are also available by anonymous FTP at:
ftp://ftp.ietf.org/internet-drafts/

---

From: "weigengyu" <[email-masked]>
Date: Tue, 22 Mar 2016 14:55:53 +0800

Hi,

I have a question.
Only 5.1 Discory is with " HTTP support :  NO" and all from 5.2 to 5.6 are 
with "HTTP support :  YES" in 5.  Resource Directory Function Set,
Why?

"
5.1.  Discovery

Interaction:  EP -> RD

   Method:  GET

   URI Template:  /.well-known/core{?rt}

   URI Template Variables:

      rt :=  Resource Type (optional).  MAY contain one or more of the
         values "core.rd", "core.rd-lookup", "core.rd-group" or
         "core.rd*"

   Content-Format:  application/link-format (if any)

   Content-Format:  application/link-format+json (if any)

   Content-Format:  application/link-format+cbor (if any)

   The following response codes are defined for this interface:

   Success:  2.05 "Content" with an application/link-format,
      application/link-format+json, or application/link-format+cbor
      payload containing one or more matching entries for the RD
      resource.

   Failure:  4.04 "Not Found" is returned in case no matching entry is
      found for a unicast request.

   Failure:  4.00 "Bad Request" is returned in case of a malformed
      request for a unicast request.

   Failure:  No error response to a multicast request.

   HTTP support :  NO
"

Regards,

Gengyu WEI
Network Technology Center
School of Computer
Beijing University of Posts and Telecommunications
-----原始邮件----- 
From: [email-masked]
Sent: Tuesday, March 22, 2016 7:34 AM
To: [email-masked]
Cc: [email-masked]
Subject: [core] I-D Action: draft-ietf-core-resource-directory-07.txt

A New Internet-Draft is available from the on-line Internet-Drafts 
directories.
This draft is a work item of the Constrained RESTful Environments of the 
IETF.

Abstract:

_______________________________________________
core mailing list
[email-masked]
https://www.ietf.org/mailman/listinfo/core

---

From: Carsten Bormann <[email-masked]>
Date: Tue, 22 Mar 2016 08:02:46 +0100

weigengyu wrote:
> Only 5.1 Discory is with " HTTP support :  NO" and all from 5.2 to 5.6
> are with "HTTP support :  YES" in 5.  Resource Directory Function Set,
> Why?

Section 5.1 says:

"
   HTTP does not support multicast and consequently only unicast
   discovery can be supported using HTTP.  Links to Resource Directories
   MAY be registered in other Resource Directories, and well-known entry
   points SHOULD be provided to enable the bootstrapping of unicast
   discovery.
"

Does that answer your question?

Grüße, Carsten

---

From: "weigengyu" <[email-masked]>
Date: Tue, 22 Mar 2016 15:28:43 +0800

Hi Carsten,

Thank you for your reply.

The following decriptions in Section 5.1  are clear,
"
   Discovery is performed by sending either a multicast or unicast GET
   request to "/.well-known/core" and including a Resource Type (rt)
   parameter [RFC6690] with the value "core.rd" in the query string.

As HTTP unicast discovery is not fobidden,
the descriptions of discovery request interface seems inconsistent to above 
statements.

"
The discovery request interface is specified as follows:

   Interaction:  EP -> RD

   Method:  GET

   URI Template Variables:

   HTTP support :  NO

regards,

Gengyu WEI
-----原始邮件----- 
From: Carsten Bormann
Sent: Tuesday, March 22, 2016 3:02 PM
To: weigengyu
Cc: [email-masked]
Subject: Re: [core] I-D Action: draft-ietf-core-resource-directory-07.txt

Section 5.1 says:

"

Grüße, Carsten