Hi list, When this question came up, I realised how little I know about ISDN data calls (the sort used for ISDN video-conferencing etc), so I thought I would solicit pointers here. I have a requirement for an Asterisk-based system to connect to an ISDN30 line (using Sangoma hardware), and to present ISDN2 sockets, probably using a Xorcom BRI unit in NTE mode. So far so good, I believe I can build that. Assuming I do no transcoding, and disable echo cancelling, will an ISDN data connection survive being passed through asterisk? Both the ISDN30, and ISDN2 use Zaptel drivers, so the passthrough should in theory be fairly painless. Thanks for any feedback. Regards, Steve