[B.A.T.M.A.N.] Hiding Local Topology – TTL

[B.A.T.M.A.N.] Hiding Local Topology – TTL

[P. Mazart]

Hello BM friends and developers,

Concerning „B.A.T.M.A.N Status Report“ from June 28, 2007:
•„2.1.7 Hiding Local Topology Information Beyond the Neighborhood“

How do I exactly set the TTL-Value for one or more of the specified 
interfaces?

Thank You,
Best Regards
Peter

Re: [B.A.T.M.A.N.] Hiding Local Topology – TTL

[P. Mazart]

Hello again,

Am Dienstag, 3. März 2009 schrieb P. Mazart:
> How do I exactly set the TTL-Value for one or more of the specified
> interfaces?

How about the vis-server? Does it need  a route back to the Source? 
(i.e. an „invisible“ back-bone-node)
How often does BM send its status to the vis server?

Best Regards
P.M.

Re: [B.A.T.M.A.N.] Hiding Local Topology – TTL

[Marek Lindner]

On Thursday 05 March 2009 18:55:16 P. Mazart wrote:
> > How do I exactly set the TTL-Value for one or more of the specified
> > interfaces?

This paper just mentions the possibilities - not all flavors implement that 
feature. As far as I know bmx (batman-experimental) supports it though.


> How about the vis-server? Does it need  a route back to the Source?
> (i.e. an „invisible“ back-bone-node)

A route back to the source? The packets sent to the vis server are UDP packets 
which require no ACK.


> How often does BM send its status to the vis server?

The interval depends on the implementation - tcpdump can help you to check 
your daemon.  :-)

Regards,
Marek

Re: [B.A.T.M.A.N.] Hiding Local Topology – TTL

[P. Mazart]

Hello & Thank's for your reply,

Am Donnerstag, 5. März 2009 schrieb Marek Lindner:
> This paper just mentions the possibilities - not all flavors
> implement that feature. As far as I know bmx (batman-experimental)
> supports it though.

Now I'm completely stuck with BM's brands. :-)

Can you say something about overhead and performance of BM in 
kernelspace compared to the udp-userspace deamon?
And devel-status of each of them?


> […] The packets sent to the vis server are UDP packets […]

Ahh. Great. Thank's for the information.

Greetings,
P.M.

Re: [B.A.T.M.A.N.] Hiding Local Topology – TTL

[P. Mazart]

Arrgh,

Am Donnerstag, 5. März 2009 schrieb P. Mazart:
> Hello & Thank's for your reply, […]
> Ahh. Great. Thank's for the information.

„Thank's“ – Shouldn't have done this…

Re: [B.A.T.M.A.N.] Hiding Local Topology ??? TTL

[Sven Eckelmann]

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On Thu, Mar 05, 2009 at 02:22:15PM +0100, P. Mazart wrote:
> Am Donnerstag, 5. März 2009 schrieb Marek Lindner:
> > This paper just mentions the possibilities - not all flavors
> > implement that feature. As far as I know bmx (batman-experimental)
> > supports it though.
> 
> Now I'm completely stuck with BM's brands. :-)
Please read http://open-mesh.net/wiki/BranchesExplained to understand basic
differences between the "brands". B.A.T.M.A.N.-adv has completely different
ideas about what to route. It is not meant as drop-in replacement and not
for any performance reasons. 

> Can you say something about overhead and performance of BM in 
> kernelspace compared to the udp-userspace deamon?
> And devel-status of each of them?
You can only compare batman-adv-kernelland and batman-adv-userspace
performance wise. Userspace has some performance problems and was meant to
test the concept of routing ethernet frames instead of creating routing
tables for ip routing.
B.A.T.M.A.N. (aka batmand) has no kernel space implementation, but a
supporting kernel module for it's gateway functionality. It should help
the gateway node to reduce the performance bottle neck by not copying all
data from kernelland to userspace.

If you would really compare batman-adv-kernelland and batmand then please
ask again - I don't have any good numbers here, but maybe somebody else
has.

If you really want to test batman-adv-kernelland then please use the
last stable release from 
 http://downloads.open-mesh.net/batman/stable/sources/batman-adv-kernelland/
and not the current version from svn. New experimental features were added
there recently and it is not in a stabilising phase at the moment.

> > […] The packets sent to the vis server are UDP packets […]
> 
> Ahh. Great. Thank's for the information.
If you want to check the amount of time between two vis packets:
 http://open-mesh.net/browser/trunk/batman/batman.c?annotate=blame&rev=1235#L1232
It is around 10000ms at the moment in batmand, but as Marek said it depends
on the implementation.

Best regards,
	Sven

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Re: [B.A.T.M.A.N.] Hiding Local Topology ??? TTL

[P. Mazart]

Hello again,

Am Donnerstag, 5. März 2009 schrieb Sven Eckelmann:
> Please read http://open-mesh.net/wiki/BranchesExplained to understand
> basic differences between the "brands".

Ok did it.
Obviously "batman" stands for an algorithm on one hand and 
implementation on the other hand… 
Can you say why there are different userspace-implementations and what 
their difference is? („Experimental is not Debian“ is what I know, yet.)

> If you would really compare batman-adv-kernelland and batmand then
> please ask again - I don't have any good numbers here, but maybe
> somebody else has.

Yes, I thought there might be differences due to the translation (e.g.) 
to sockets inside the kernel when using batmand or something.

But as far as got to know now the originatorpacketsize of batmand 
(≈60bytes) is small compared to the sizes of olsr's anyway. (≈500bytes 
with 300 nodes(?))

Thanks for your help
P.M.

Re: [B.A.T.M.A.N.] Hiding Local Topology ??? TTL

[Sven Eckelmann]

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On Wednesday 11 March 2009 14:20:49 P. Mazart wrote:
> Hello again,
>
> Am Donnerstag, 5. März 2009 schrieb Sven Eckelmann:
> > Please read http://open-mesh.net/wiki/BranchesExplained to understand
> > basic differences between the "brands".
>
> Ok did it.
> Obviously "batman" stands for an algorithm on one hand and
> implementation on the other hand…
Correct

> Can you say why there are different userspace-implementations
bmx is more or less an fork of batmand where Axel Neumann does some of his 
work and tried his ideas.

> and what
> their difference is? („Experimental is not Debian“ is what I know, yet.)
There is a document written by Axel to describe what he tries to do or did. I 
don't if it is up to date, but it is currently the best hint I can give you:
 http://downloads.open-mesh.net/batman/misc/bmx.pdf

Best regards,
	Sven

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Re: [B.A.T.M.A.N.] Hiding Local Topology ??? TTL

[P. Mazart]

Am Mittwoch, 11. März 2009 schrieb Sven Eckelmann:
> There is a document written by Axel to describe what he tries to do
> or did. I don't if it is up to date, but it is currently the best
> hint I can give you:
> http://downloads.open-mesh.net/batman/misc/bmx.pdf

Very Cool,
I'll read soon.
Thanks
P.M.