Subject: [6lowpan] agenda items for next meeting

From: Geoff Mulligan <[email-masked]>
Date: Wed, 09 Mar 2011 17:33:59 -0700

I think that we now have two presentations: 
  - 6lowpan proxy for ND
  - ipv6 over bluetooth low-energy

Other topics:
  - ND issues
  - Carstens general packet compression
  - new work/rechartering

Any others topics for the agenda?

        geoff

---

From: Zhen Cao <[email-masked]>
Date: Thu, 10 Mar 2011 20:19:37 +0800

Hi, Chairs,

If we still have room, I'd like to request a short slot to present the
6lowpan gateway consideration draft
http://www.ietf.org/internet-drafts/draft-cao-lwig-gateway-00.txt

Thank you for your consideration.

On Thu, Mar 10, 2011 at 8:33 AM, Geoff Mulligan <[email-masked]> wrote:
> _______________________________________________
> 6lowpan mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/6lowpan
>

-- 
Best regards,
Zhen

---

From: "Carles Gomez Montenegro" <[email-masked]>
Date: Thu, 10 Mar 2011 18:02:50 +0100 (CET)

Dear folks,

I have been very pleased to see that there is a new 6LoWPAN work item
which deals about transmission of IPv6 packets over Bluetooth Low Energy
(BT-LE). I would like to contribute to this topic.

I will next give some comments on draft-patil-6lowpan-v6over-btle-00:

- The introduction mentions some typical performance values of BT-LE. It
might be interesting to add more detail in a new (informative) section,
which might include text about the following:

   o The maximum rate of L2CAP payload per time unit is roughly 271 kbps
under ideal conditions. This performance parameter decreases strongly
with BER (and depends also on BT-LE parameters).

   o Data transfer can happen from once every 7.5 ms up to once every 32
seconds, depending on BT-LE parameter settings.

   o Data delivery latency once a BT-LE Link Layer connection is created
is roughly equal to 1 ms.

- BT-LE defines two Link Layer roles: the master and the slave. A device
in the master role is assumed to be less constrained than a device in the
slave role. The master can manage multiple simultaneous connections with a
number of slaves, whereas a slave is connected to a single master. Hence,
a BT-LE network (i.e. a BT-LE piconet) follows a star topology.

- Master and slave can correlate with 6LBR and 6LN (host). A BT-LE piconet
running IP would be a single-hop IP network.

- A significant difference between IEEE 802.15.4 and BT-LE is that the
former supports the mesh topology (and requires a routing protocol),
whereas BT-LE (per se) does not currently support the formation of mesh
networks.

- Section 3 states the 6LoWPAN specs that have to be supported by a BT-LE
node. It may be interesting to see which mechanisms of the current 6LoWPAN
specs are not necessary for BT-LE (e.g. the mesh under header of RFC 4944
will not be used since BT-LE does not support mesh topologies).

- The BT-LE L2CAP MTU (i.e. maximum L2CAP payload size) has to be
considered, as this is one of the most challenging elements. This MTU is
equal to 23 bytes. This means that a compressed IPv6 header containing
global addresses (which according to section 3.2 is 26 bytes) does not fit
into a single BT-LE packet (!!). In addition, the header overhead of BNEP
has to be taken into consideration.

- A mechanism for stateless address autoconfiguration based on BT-LE
identifiers is needed.

- The security considerations section may benefit from discussing the
following:
   o  BT-LE Link Layer supports encryption and authentication by using the
CCM mechanism and a 128-bit AES block cipher. CCM does not consume
bytes from the 23-byte L2CAP MTU (since these bytes have their own
field in the link layer data unit).
   o  Whereas key management is out of scope of IEEE 802.15.4 specs, BT-LE
provides SMP, a protocol for key management.

Some minor details:

- Section 2. I am not sure about whether the term 'BT-LE Physical Layer'
that appears at the bottom of the protocol stack includes also 'BT-LE Link
Layer'. Maybe this layer could be explicitly included in the figure.

- Section 3.1. "A BT-LE needs" -> "A BT-LE node needs"

All the best,

Carles

---

From: <[email-masked]>
Date: Thu, 10 Mar 2011 17:19:52 +0000

Carles,

Rev 1 of the I-D is just a skeleton that I needed to submit to meet the Rev 0 deadline.
Please wait for Rev 1 of the I-D by end of tomorrow for a better structure to the document.

Rgds,
-Raj

-----Original Message-----
From: ext Carles Gomez Montenegro [mailto:[email-masked]] 
Sent: Thursday, March 10, 2011 11:03 AM
To: 6lowpan
Cc: Patil Basavaraj (Nokia-MS/Dallas); Savolainen Teemu (Nokia-MS/Tampere); Nieminen Johanna.1 (Nokia-NRC/Helsinki); Isomaki Markus (Nokia-CIC/Espoo); [email-masked]
Subject: IPv6 over BT-LE

Dear folks,

Some minor details:

All the best,

Carles

---

From: "Carles Gomez Montenegro" <[email-masked]>
Date: Thu, 10 Mar 2011 21:30:40 +0100 (CET)

Hi Raj,

First of all, thanks for starting work in IPv6 over Bluetooth Low Energy.
I believe this will be an important item in order to expand even more the
Internet of Things. Bluetooth Low Energy is indeed expected to be present
in many daily life scenarios.

> structure to the document.

Sure! :)

All the best,

Carles