From mboxrd@z Thu Jan 1 00:00:00 1970 From: Axel Neumann Subject: Re: [B.A.T.M.A.N.] dynamic gateway / hna / services Date: Sat, 4 Aug 2007 11:43:36 +0200 References: <20070803113132.f7ij8uf21xwsog8o@webmail.ddmesh.de> In-Reply-To: <20070803113132.f7ij8uf21xwsog8o@webmail.ddmesh.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200708041143.37165.axel@open-mesh.net> Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: The list for a Better Approach To Mobile Ad-hoc Networking Hello! On Freitag 03 August 2007, Freifunk Dresden wrote: > Hello, > I didn't get the email for this request, so the mailling list thread > my be brocken. strange, anybody else experienced problems? [...] > > > I'm currently checking how the HNA is working, but until now I can not [...] > I have checked out the rv491 and it seems working. In my test environment I > use a laptop (i386) and two wrt54gl. The wrt shows at "-d3" that the > announced HNA is added/deleted every 1-5 seconds. The wrt that has a > greater distance (5meter 2 walls between) adds and deletes the HNA in a > highe frequency than the > wrt that is about 50cm away. > I think that HNA should not be deleted to fast because someone that is > using this "bad" connection will get often error messages during > surfing that the rout e is not found. It would be better if just the > connection slow because of transmistion errors. that should not be the case! You say even with the stable connection to your near-by WRT that the HNA is added/deleted every 1 - 5 SECONDS ! And even more often at the distant WRT (so added/deleted every SECOND ?). Can you describe the setup and parametrization in more detail? > > [...] > > > > > Another Idea of the "-m" is to differenciate this parameter to -M > > > <"message"> and -m . by calling batmand -c -m send-script, > > > batmand can setup stdin/stdou as binary file handle and fill a user-OGM > > > with binary data that is then send. > > > > Even if such message-flooding ist not implemented I just thought of > > whether there exist some standardized formats to announce such > > services (maybe the community network markup language CNML idea) ? > > ciao, axel > > I have looked through the code and have seen that the HNA is simply > appended to > the end of a message. if we want to send other information a TLV structure > is needed (Tag-length-value). Batmand can ignore unknown Tags and is > still working in the network. At moment the whole network needs an > update at same time, because old batmand will interpret any data as HNA. > I hope I'm not wrong :) Do you really think of a human-readable ascii string that you want to flood with an arbitrary length over the mesh with content like: "Hello take a cool beer and see my fancy cool movie torrent-server at 105.10.bla.bub". Iam not against such communication but... default OGM size: 10 bytes OGM + HNA size: 15 bytes OGM + example-TLV-ascii message: 95 bytes ... I am a bit scared about the amount of data which would be flooded over the mesh (at every originator interval) with no means for stopping the sources. Therefore i asked if anybody knows a decent forman for describing such services (preferably in a short and machine readable notation). Perhaps another approach is to just have a kind of key-to-service list (similar to /etc/services with a 16bit key) just roughly indicating the type of offered service together with another port/ip where further information (of arbitrary length) about the indicated service can be retrieved. This would also allow to outsource part of the service-discovery to another daemon. greetings, axel