From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [Bluez-devel] Development of a Bluetooth-LAN-Accesspoint From: Marcel Holtmann To: Boris =?ISO-8859-1?Q?W=FCst?= Cc: BlueZ Mailing List In-Reply-To: <00a101c4c029$2c66e730$2301a8c0@boris> References: <00a101c4c029$2c66e730$2301a8c0@boris> Content-Type: text/plain Message-Id: <1099325174.16247.144.camel@pegasus> Mime-Version: 1.0 Sender: bluez-devel-admin@lists.sourceforge.net Errors-To: bluez-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: List-Post: List-Help: List-Subscribe: , List-Archive: Date: Mon, 01 Nov 2004 17:06:14 +0100 Hi Boris, > still i have more a logical than a technical problem. i hope someone > can help: > > we (my projectteam) want to develop an bluetooth-lan-accesspoint based > on the BlueTarget-Controller from SND (perhaps someone knows the > controller) for our university. i have thought about to use the > rfcomm-layer to handle the connections and the low level data > transfer. on top of the rfcomm-connections i want to set up an normal > ppp-connection. speaks something against this concept? have anyone a > better solution? yes, because "LAN access using PPP" is a deprecated profile. Use the PAN profile instead. > now to the problem(s): > > (1) we want to design an accesspoint that connects automatically to > all bt-devices that are located in its range, so that a lan-access > supported immediately and it's guaranteed that the bt-accesspoint is > the master at all communications? how can we implement an automatic > connection establishment on the rfcomm-layer and how we can make sure > that the bt-accesspoint is always master that parks and activates the > devices automatically depended on the data transfer(so that can be > more devices than 7 connected to the lan)? what do we have to consider > with the authentication? can we avoid it or switch it off at both > sides of connection? when the connections established how we can > manage them and the different channels to the connections? The master point does not count, because you can switch the roles at any time. What I don't understand is why the access point should initiate the connection. What kind of clients do you wanna support? > (2) when we use a ppp-connection from bt-devices to the accesspoint, > every device needs an ip and the accesspoint as gateway. how can we > realize the assignment of the ip-adresses an the gateway to the > bt-devices controlled by the accesspoint? the major problem at this > concept is that the BlueTarget-Controller is a pure microcontroller an > provides a own bt-stack. so on it can't be run services how pppd or > pand. but the controller as an lan-interface and must therefor > understand tcp/ip. how we can emulate a ppp-connection with a > bt-stack(bluez) avoiding high expense of development? are there some > documentations and/or program examples about this topic?? have anyone > implemented something compareable?? I don't understand that. Explain what the BlueTarget controller is and what it is doing actually. > (3)the last problem is the connection speed. we have set up an test > environment composed of a PDA and a linuxsystem with the bluez-stack > and a bt-usb-donlge. we have only achieved max. 16KB/s at the best > bt-connection qualtity, only one bt-connection and ACL. why can't we > achieve approximately the max. speed (95KB/s) of the connection? how > does it look with serveral connections? share all connections these > 16KB/s? how we can advance the connection-speed? is one possibility to > use more than one rfcomm-connection (more than one channel) for a > ppp-connection? have anyone a solution? The Bluetooth bandwith is shared within the complete piconet and so more RFCOMM channels won't help. However the 16 KB/s must be a problem of your PDA, because you will get around 60-70 KB/s depending on your payload of the data. > i hope you guys can help me with these problems. perhaps also by > documentations of previous projects or links to the web. when someone > of you have a lot of experience in the development in this direction, > i would be grateful when you lend yourself as permanent contact > person. thanks to everyone who helps ;D Feel free to ask on the mailing list, but lending a developer costs money ;) Regards Marcel ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click _______________________________________________ Bluez-devel mailing list Bluez-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-devel