Hi Adam, hi Cenk,
Has anyone tested the amount of time it takes for a node (full or reduced
function) to join an RPL routed 6lowpan network?
Not a particular range, but I can confirm that the time varies until a RPL
topology converges in whole, and that it varies for a single node to join.
Regarding the further discussion, I'm not convinced if we should send periodic
DIS messages.
Even if they get lost, DIOs are disseminated repeatedly by all nodes in a DODAG
when trickle fires [1].
Concerning LLNs I don't like to send additional packets periodically at all.
In my opinion it just drains the energy of a node with small to no benefit.
Even if a node is not answered with a DIO directly when sending a DIS,
eventually a DIO will arrive from a neighbor node (assuming one is present).
Resetting the trickle timer from applications sounds like a good opportunity
for debugging and testing things.
Just as Adam I also think such feature should be only available for debugging
and testing.
Resetting the trickle timer in normal operation from an application sounds
for me like interfering with the routing protocol,
or even attacking the topology ;)
...anything like this should be runtime configurable as long as such
configurability doesn't adversely effect battery life, code
complexity/readability, etcetera in a massive way
I think the most impacting problem with such approach is that every convenience
function/structure we provide will produce more bytes used on the ROM and RAM.
RPL is used on nodes with few kB RAM and ROM and it must share this room with a
network stack and further productive applications.
Concerning this, I obviously vote for compile time configuration :)
These are just some thoughts and my personal opinion.
Best regards,
Martin
[1] https://tools.ietf.org/html/rfc6550#section-8.3
Von: devel [devel-boun...@riot-os.org] im Auftrag von Adam Hunt
[voxa...@gmail.com]
Gesendet: Freitag, 22. Mai 2015 07:09
An: RIOT OS kernel developers
Betreff: Re: [riot-devel] Association time in mobile RPL/6lowpan networks
I like the idea of sending periodic DIS messages but I absolutely believe that
it should not only be optional but that it be configurable at runtime.
Honestly, I am a firm believe in the idea that virtually anything like this
should be runtime configurable as long as such configurability doesn't
adversely effect battery life, code complexity/readability, etcetera in a
massive way. This is something that Linus has absolutely right with Linux;
policy don't shouldn't be written in kernel space stone; everyone had different
requirements and altering the way an OS behaves from the (sensible) defaults
shouldn't require altering mainline code and maintaining a private branch if at
all possible. Ideally everything should be runtime configurable, if that's not
possible it should be configurable at boot, if that for some reason isn't
possible it should be compile time configurable.
On Wed, May 20, 2015, 11:53 PM Joakim Gebart
joakim.geb...@eistec.semailto:joakim.geb...@eistec.se wrote:
On May 21, 2015 8:37 AM, Cenk Gündogan
cenk.guendo...@fu-berlin.demailto:cenk.guendo...@fu-berlin.de wrote:
Hey Adam,
I am currently adopting RPL to our new network stack and while doing so,
I also added sane functionalities which were plainly missing in the old
implementation.
This also includes sending a DIS when initializing RPL for the first time.
However, I am just now realizing that such a DIS can get lost in our typical
LLN case - it may make sense to send a DIS periodically until a DIO is
received?
Does anyone has an opinion on this?
Good idea, as long as the periodic interval is large enough to not waste power
or cause interruptions in normal traffic if there is no other rpl node on the
network.
Forcing a DIS from userspace sounds like a good feature. It may help in
testing/debuging the dodag tree interactively.
I also thought about reseting the trickle timer from userspace to enforce
DIOs.
+1 for this. It would be nice to have some shell commands to call these
functions too.
Best regards,
/Joakim
Cheers,
Cenk
On 21.05.2015 04:36, Adam Hunt wrote:
That's great. Is there any way to force a node to send a DIS message from
userspace?
On Wed, May 20, 2015, 5:34 PM Oleg Hahm
oliver.h...@inria.frmailto:oliver.h...@inria.fr wrote:
Hi Adam!
Has anyone tested the amount of time it takes for a node (full or reduced
function) to join an RPL routed 6lowpan network? I realize that it's very
likely to vary quite a bit depending on the network, I'm just curious if
anyone has an approximate range.
As you said: it depends quite a bit on the network and the parameters. Since
nodes on the current RPL implementation won't send proactively DIS messages
and the interval of sending DIOs increases, it will usually take just a
couple
of seconds if you try to join the network right after bootup, but can take
