Why do you need 2 channels? Why not use one host as a 'master', running NAT and PPP out its modem, and the other host as a 'slave' connected to the 'master' host through their ethernet ports?
Harry ----- Original Message ----- From: "Chris McKenzie" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, September 20, 2002 2:32 PM Subject: [vox-tech] Modem question . . . I think it is possible > I know the post is a few days old but I was intrigued with the idea. > modems capable of the v.34 standard have something called an auxiliary > channel by which it can exchange information on such things as line > quality. It can code using nonlinear, precoding, and 16-trellis along > with most modern being able to do 32 and 64 state trellis depending of > course on what type of bit (dibit etc) you want to transmit at. Here is > the trick: Because of the ability to use such things as assymetrical > transmission and the use of trellis coding, and echo cancellation, each > modem will have an idea of sender and reciever. For the first modem, the > other modem will be a sender and the other end of the ppp will be a > sender. This essentially sets what could be a master slave model in order > to do correct splitting, with hopefully little interference (via the > trellis encoding). Here is how it would work: > > Computer 1 is master > Computer 2 is slave > > ppp ISP is ISP > > Initiate the connection with the master to ISP and send a request for > 16-state trellis encoding at 14400 bps. Ask for 16-state send and > 16-state receive. Put the master on 32-state trellis recieve > without confirmation via the auxiliary making each other > baud recieved as null or noise. > > Place slave in 16-state trellis before connecting. Because of the > trellis, it will interpret the data being sent as noise and adjust phase > correctly to the nulls. > > When it sends out a request, the ISP with 16 state trellis which is synced > with the master will interpret it as noise and ignore it. However, the > master will take the signals in as extra data. As long as the master can > split every other bit and maintain parity and whatever, it has now set up > two channels, one 16 bit with the other laptop and one 16 bit with the > ISP. Each other end will take the 'excess' data as noise and ignore it > because it is not in sync. You now have two linked connections over one > line. > > Truly, the slave still goes to the master which in turns goes to the ISP, > however, this would be a sane operation of 14400 bps and a technical modem > split. Implementing it however, is another thing . . . shouldn't be that > difficult but also shouldn't be that worthwhile. Anyway, that is all for > now. > > > Sincerely, > Christopher J. McKenzie > > [EMAIL PROTECTED] > [EMAIL PROTECTED] > H: +1 818.9917724 > C: +1 818.4293772 > 1815 Mesa Ridge Ave > Westlake Village, CA 91362 > > _______________________________________________ > vox-tech mailing list > [EMAIL PROTECTED] > http://lists.lugod.org/mailman/listinfo/vox-tech _______________________________________________ vox-tech mailing list [EMAIL PROTECTED] http://lists.lugod.org/mailman/listinfo/vox-tech
