Problem with ISDN client/server 128K Bundling

RouterOS General
1

Hi,

I’m trying to connect two machines with PPP over ISDN and I’m facing a problem I can’t solve. I have one ISDN PCI card installed on each end (one Fritz and one Openvox with an HFC chip).
I’ve made an ISDN client interface on one end and an ISDN server interface on the other. They connect and transfer data very well when I’m using only one of the ISDN channels. But if I enable the “bundle 128k” option, they connect for a couple of seconds with both channels and then the interface drops and tries to reconnect.

I’ve tried everything I could think of: switched the client and server roles for the cards, tried to connect with an old Zyxel prestige 201 (which is basically a PPP client) and also tried to connect from a windows machine with an external ISDN modem. In all cases I get the same behavior from the ISDN server side. I can connect with 128k to Internet providers with no issues, from both ISDN cards and the test modem.

Also, I can connect with two seperate 64K interfaces at the same time with no problem. I just need a way to bundle these connections and get the total bandwidth for a small videoconferencing application.

Maybe someone can help with this?

Thanks in advance.

2

Hello again,

I finally found a workaround for this problem, using two different ISDN channels and NTH mangle rules to split traffic in two. It’s not an optimal solution, but I think it will work well. But I would like to hear if anyone has an answer to the disconnection problem when using 128K bundle, since this would work better and allow me to use other equipment as well. I’m almost convinced this is an ISDN server side problem, since I can connect to dialup providers with 128K.

Thanks

3

If this is helpful, I would like to add that when an ISDN client connects to the server at 128K, the server status reports 64000 in the “connect speed” field, even though there are two ISDN channels connected and the client reports a connection of 128000. I really hope someone has a solution or an idea to offer.

Thanks.