Subject: [6lo] #14 (routing-dispatch): More optimal compression of 6LoRH

From: "6lo issue tracker" <[email-masked]>
Date: Sat, 23 Jan 2016 12:03:08 -0000

#14: More optimal compression of 6LoRH

 From: [email-masked] [mailto:[email-masked]] On
 Behalf Of Simon Duquennoy
 Sent: mardi 19 janvier 2016 20:32
 To: Pascal Thubert (pthubert) <[email-masked]>
 Cc: Tengfei Chang <[email-masked]>; [email-masked]; Routing Over
 Low power and Lossy networks <[email-masked]>; [email-masked]
 Subject: Re: [6lo] [6tisch] Proposed improvement in RH3-6LoRH

 Hi Pascal,

 I feel we need to make sure any valid RH3 can be compressed with 6LoRH.
 This way, RPL implementations do not need to be aware of 6LoRH.
 For the compression level, we could maybe optionally carry a full value
 inline (or well, it's only 4 bits..).
 As for using the root's address as reference for compression, although the
 idea makes sense, I'm afraid it makes it complicated to compress RH3,
 where the prefix is copied from the IPv6 destination.

 Thanks,
 Simon

 On Tue, Jan 19, 2016 at 8:15 PM, Pascal Thubert (pthubert)
 <[email-masked]> wrote:
 Hello Simon:

 You can get different cmpri and cmpre values, by placing 2 different
 RH3-6LoRH header. Having as many 6LoRH headers allows you to compress that
 even more, like having intermediate cmprx values should you need that.

 But ultimately what we compress is the RH0 format with the rules of RH3,
 knowing that apart from the rules RH3 is just a compression of RH0.

 And then 6LoRH can enable a better compression when coalescing from the
 root’s address.

 I agree that we placed an artificial limit with the power of 2, to avoid
 consuming too much type space. But if the power of 2 does not much the
 real world use cases and needs, now is a good time to change it.

 Do you have an opinion on that?

 Pascal

 From: [email-masked] [mailto:[email-masked]] On
 Behalf Of Simon Duquennoy
 Sent: mardi 19 janvier 2016 18:53
 To: Tengfei Chang <[email-masked]>
 Cc: Pascal Thubert (pthubert) <[email-masked]>; [email-masked];
 Routing Over Low power and Lossy networks <[email-masked]>; [email-masked]
 Subject: Re: [6lo] [6tisch] Proposed improvement in RH3-6LoRH

 Hi Pascal,

 One thing that bugs me is that RH3-6LoRH seems to be an alternative to RH3
 rather than a strict compression of it. For instance, a RH3 using
 different cmpri and cmpre values, or using non power-of-two, can not be
 compressed with 6LoRH. And the discussion on copying the prefix form the
 DAG root is also a departure from RH3.
 Am I missing something?

-- 
-------------------------+-------------------------------------------------
 Reporter:               |      Owner:  draft-ietf-6lo-routing-
  [email-masked]     |  [email-masked]
     Type:  defect       |     Status:  new
 Priority:  major        |  Milestone:
Component:  routing-     |    Version:
  dispatch               |   Keywords:
 Severity:  -            |
-------------------------+-------------------------------------------------

Ticket URL: <https://trac.tools.ietf.org/wg/6lo/trac/ticket/14>
6lo <https://tools.ietf.org/6lo/>

---

From: "6lo issue tracker" <[email-masked]>
Date: Sat, 23 Jan 2016 12:03:38 -0000

Changes (by [email-masked]):

 * owner:  [email-masked] => [email-masked]

-- 
--------------------------------+---------------------------------
 Reporter:  [email-masked]  |       Owner:  [email-masked]
     Type:  defect              |      Status:  new
 Priority:  major               |   Milestone:
Component:  routing-dispatch    |     Version:
 Severity:  -                   |  Resolution:
 Keywords:                      |
--------------------------------+---------------------------------

Ticket URL: <https://trac.tools.ietf.org/wg/6lo/trac/ticket/14#comment:1>
6lo <https://tools.ietf.org/6lo/>