Comment 7 for bug 269329

Revision history for this message
Jamie Lokier (jamie-shareable) wrote :

I'm under the impression that 3G broadband over Bluetooth can be done over:

    - PAN Bluetooth protocol
    - DUN Bluetooth protocol
    - RFCOMM Bluetooth protocol

PAN does not use PPP. Rather, you activate the PAN link, and that gives you a packet network, like ethernet. Then you can use DHCP etc. and it generally works to give you an internet connection, although sometimes a reduced MTU is required - not always reported correctly over DHCP.

Some phones support more than one of these. I didn't see any options in NetworkManager's Edit Connections window to choose which of the Bluetooth protocols to use.

When I did fill in some dialup settings (for the 3 network in the UK), they looked fine, but I didn't find anywhere to activate the connection having added it! The GUI looked to me like right-clicking on a connection ought to enable/disable it or something, but no such behaviour. The connection did not appear in the main NM list - only my wireless APs, and (bizarrely) "ifupdown (tap0)" (+tap1, tap2) under wired.

It's only on reading this bug report that (doh!) I realise "mobile broadband" doesn't mean mobile broadband the way I've been used to it - it means only via a built-in or USB 3G modem, doesn't it?

RFCOMM should be really easy to support. It's simply dialup with PPP, except you use /dev/rfcomm0 as the serial port. It's possible that it can take up a channel of the phone's mobile link, preventing web browsing and other data access on the phone itself. PAN seems better in this respect.

On Hardy, I tested Bluetooth RFCOMM and USB ACM for broadband, and found Bluetooth slightly slower but it seemed to use less power than USB, so I've used Bluetooth on Hardy ever since.
When I got a new phone, I switched to Bluetooth PAN.

On Hardy I had to kill NM to use 3g broadband. On Intrepid, I was excited to see the "mobile broadband" under Edit Connections, and disappointed to find this doesn't mean via Bluetooth, which surely is the most common way of doing it with a mobile phone? I'm hoping I'll be able to use PAN the same way as I did in Hardy, but haven't had success yet.