Subject: [core] #356: Which IPv6 multicast scopes for the "All CoAP Nodes" address?

From: "core issue tracker" <[email-masked]>
Date: Wed, 27 Nov 2013 13:19:11 -0000

#356: Which  IPv6 multicast scopes for the "All CoAP Nodes" address?

 in coap-18 it mentions for the IPv6 “All CoAP Nodes” address:

 Note that there is a distinct multicast address
       for each scope that interested CoAP nodes should listen to; CoAP
       needs the Link-Local and Site-Local scopes only.

 which could raise some interoperability concerns:
 -       CoAP nodes are not obliged to join any of these addresses; so
 multicast discovery may not work in practice.
 A client may be tempted to instead use the “All Nodes” link-local IPv6
 multicast address to send out a CoAP request, since IPv6 / 6LoWPAN-ND
 requires joining this address.
 -       CoAP nodes only join the link-local and/or site-local scoped
 address, not others (admin-local, or the new “realm-local” defined in
 draft-droms-6man-multicast-scopes-02)
 So a discovering client using e.g. admin-local may not find any CoAP
 nodes.

 My goal was to write some guidelines in groupcomm what IPv6 / IPv4
 multicast addresses a CoAP server should join, and which addresses a
 discovering client should use.
 For now I will base on the information that core-coap provides; adding
 that a server SHOULD join both the link-local and site-local “All CoAP
 nodes” IPv6 multicast addresses.

-- 
-------------------------+-------------------------------------------------
 Reporter:               |      Owner:  draft-ietf-core-
  [email-masked]  |  [email-masked]
     Type:  protocol     |     Status:  new
  defect                 |  Milestone:
 Priority:  major        |    Version:
Component:  groupcomm    |   Keywords:
 Severity:  -            |
-------------------------+-------------------------------------------------

Ticket URL: <http://trac.tools.ietf.org/wg/core/trac/ticket/356>
core <http://tools.ietf.org/core/>

---

From: "core issue tracker" <[email-masked]>
Date: Thu, 28 Nov 2013 11:47:49 -0000

Changes (by [email-masked]):

 * status:  new => closed
 * resolution:   => fixed

Comment:

 In groupcomm [1560]: reference to draft-droms-6man-multicast-scopes
 included; guideline added for CoAP server to join link-local and site-
 local "All CoAP Nodes" address.

-- 
-------------------------+-------------------------------------------------
 Reporter:               |       Owner:  draft-ietf-core-
  [email-masked]  |  [email-masked]
     Type:  protocol     |      Status:  closed
  defect                 |   Milestone:
 Priority:  major        |     Version:
Component:  groupcomm    |  Resolution:  fixed
 Severity:  -            |
 Keywords:               |
-------------------------+-------------------------------------------------

Ticket URL: <http://trac.tools.ietf.org/wg/core/trac/ticket/356#comment:1>
core <http://tools.ietf.org/core/>