Subject: [6lowpan] #84: Unicast RA clarification

From: "6lowpan issue tracker" <[email-masked]>
Date: Thu, 08 Jul 2010 13:50:40 -0000

#84: Unicast RA clarification
--------------------------------+-------------------------------------------
 Reporter:  zach@…              |       Owner:     
     Type:  enhancement         |      Status:  new
 Priority:  trivial             |   Milestone:     
Component:  nd                  |     Version:     
 Severity:  -                   |    Keywords:     
--------------------------------+-------------------------------------------
 Issue from ZigBee IP testing:

 RA unicast/broadcast: regarding including SLLAO to ‘enable’
 multicast. It does not specify in 4861 that you should unicast It’s
 just a MAY and in fact suggests it probably wouldn’t be done
 (section 6.2.6). Should RS have SLLAO in Src LL64 Dst All routers
 multicast, SLLAO. Or should RA be MAC level broadcast? (IPv6
 multicast?)

 Proposed solution:

 it is correct that 4861 discourages unicast RA, so perhaps we should add
 some text making it clear that lowpan-nd ignores such discouragement.
 Something like this in section 6.3:

 FROM:

   A router processes Router Solicitation messages as specified in
   [RFC4861].  The differences relate to the inclusion of Authoritative
   Border Router options in the Router Advertisement (RA) messages.

 TO:

   A router processes Router Solicitation messages as specified in
   [RFC4861].  The differences relate to the inclusion of Authoritative
   Border Router options in the Router Advertisement (RA) messages, and
   the exclusive use of unicast Router Advertisements.

 and then add a paragraph later in 6.3 saying:

   Unlike RFC4861 which suggests multicast Router Advertisements, this
 specification optimizes the exchange by always unicasting RAs in response
 to RSs. This is possible since the RS always includes a SLLA option, which
 is used by the router to unicast the RA.

-- 
Ticket URL: <http://wiki.tools.ietf.org/wg/6lowpan/trac/ticket/84>
6lowpan <http://tools.ietf.org/6lowpan/>

---

From: "6lowpan issue tracker" <[email-masked]>
Date: Mon, 12 Jul 2010 20:05:34 -0000

#84: Unicast RA clarification
--------------------------------+-------------------------------------------
 Reporter:  zach@…              |        Owner:        
     Type:  enhancement         |       Status:  closed
 Priority:  trivial             |    Milestone:        
Component:  nd                  |      Version:        
 Severity:  -                   |   Resolution:  fixed 
 Keywords:                      |  
--------------------------------+-------------------------------------------
Changes (by zach@…):

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

Comment:

 - Done in nd-11

-- 
Ticket URL: <http://trac.tools.ietf.org/wg/6lowpan/trac/ticket/84#comment:1>
6lowpan <http://tools.ietf.org/6lowpan/>