Hi dear Marvin and other guys, After testing different initial strings, these results have been obtained (Ubuntu 8.10 on Dell 6000, with Conexant modem): 1. ATQ0 V1 E1 S0=0 &C1 &D2 +MS=V90 : no disconnections but the speed is slow 2.AT&FE0V1S0=0L3&C1&D2+MR=2;+DR=1;+ER=1;W2 (I found this init string from Dell driver .inf file) : no disconnections, the speed become better than 1 but still slow 3. AT&F E1 V1 X1 S10=250 S7=90 : same as 2 4. ATQ0 V1 E1 S0=0 &C1 &D2 +MS=V90,0,,,44000,52000 : first the speed was good but I have disconnections. After changing my ISP and modem type to ISDN and phone number to DT971.... in gnome-ppp the disconnections also have gone :-) Finally, thanks to everyone especially Marvin. Cheers, Habib Seifzadeh ----- Original Message ---- > From: Marvin Stodolsky <marvin.stodolsky@xxxxxxxxx> > To: Habib Seifzadeh <habibseifzadeh@xxxxxxxxx> > Sent: Wednesday, November 26, 2008 6:58:15 AM > Subject: Re: What's the best init string for noisy lines? > > Please write this up clearly as a report to the List, > where it will acquire a URL we can pass to others. > > MarvS > > On Tue, Nov 25, 2008 at 3:49 PM, Habib Seifzadeh > wrote: > > Wow! you're really a great man..... > > Thanks for thinking of me.... > > > > Dear Marvin, > > I finally figured out that the problem is not V92 itself. But the problem is > parameters which we pass to the compression protocol. > > > > This means that even if I use " Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +MS=V92", the > line isn't disconnected, but the speed remains slow. > > Once I pass some parameters to each compression protocol (for example V90), > like "Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +MS=V90,1,28800,33600,28800,56000", the > speed becomes good but disconnections start coming. > > > > The final solution in which not only the speed is good but also the number of > disconnection is reasonable (about every 15 minutes) is > > 1) using "Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +MS=V90,0,,,44000,52000" as initial > string > > 2) set passive, lcp-echo-failure and lcp-echo-interval to zero in > /etc/ppp/options > > 3) change my ISP > > > > But, I definitely check the initial string you send..... > > > > By the way, since I have unsubscribed from linmodems.org mailing list, my > email isn't archived in this useful site. So, If you like, please send the > discussion to the mailing list for other people. > > > > Sincerely, > > Habib Seifzadeh > > > > > > > > ----- Original Message ---- > >> From: Marvin Stodolsky > >> To: Habib Seifzadeh > >> Sent: Tuesday, November 25, 2008 9:49:13 PM > >> Subject: Re: What's the best init string for noisy lines? > >> > >> Just forwarding the message below. I am not sure of the rational of > >> Init2 = AT&F E1 V1 X1 S10=250 S7=90 > >> > >> MarvS > >> > >> On Tue, Nov 25, 2008 at 12:51 PM, Jayant Ogale wrote: > >> > hi, > >> > you can try following string for a noisy line. > >> > AT&FE1V1X1S10=250S7=90 > >> > you can try X4 in place of X1 or delete it all together. > >> > jayant > >> > > >> > On Thu, Nov 20, 2008 at 8:50 PM, Marvin Stodolsky > >> > wrote: > >> >> Habib, > >> >> The V32, V90, V92 specify different compression protocols. > >> >> Evidently your IPs V92 is not fully Linux compatible, > >> >> so you have to fall back to V34 or V90. > >> >> > >> >> These ha ve worked in the past with +MS=34 or +MS=90 > >> >> Thus it is surprizing that you needed the +MS=V34 > >> >> Please recheck. > >> >> > >> >> There is nothing else I'm aware of which could increase speed. > >> >> > >> >> You might read /etc/ppp/options or > >> >> $ man pppd > >> >> about adjusting the MTU (tranfer unit size), but I have no intuition > >> >> whether it will help. > >> >> > >> >> MarvS > >> >> > >> >> On Thu, Nov 20, 2008 at 8:46 AM, Habib Seifzadeh > >> >> wrote: > >> >>> Hello again Marvin, > >> >>> Thanks for your kindness > >> >>> > >> >>> Although the init string which you sent works properly, but the Internet > >> speed has been become slow. Is there any way to bring speed and not > >> >>> disconnecting together? Is there any site which explains how I can tune > >> >>> my connection by AT commands? > >> >>> > >> >>> Sincerely, > >> >>> Habib Seifzadeh > >> >>> > >> >>> > >> >>> ----- Original Message ---- > >> >>>> From: Marvin Stodolsky > >> >>>> To: Habib Seifzadeh > >> >>>> Cc: discuss@xxxxxxxxxxxxx > >> >>>> Sent: Thursday, November 20, 2008 3:08:27 AM > >> >>>> Subject: Re: What's the best init string for noisy lines? > >> >>>> > >> >>>> Habib > >> >>>> > >> >>>> If V90 also works, transmission will be faster, try > >> >>>> Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +MS=V90 > >> >>>> > >> >>>> MarvS > >> >>>> > >> >>>> On Wed, Nov 19, 2008 at 2:07 PM, Habib Seifzadeh > >> >>>> wrote: > >> >>>> > > >> >>>> > > >> >>>> > First of all, thanks so much guys, especially Marvin and John, > >> >>>> > Right now, I'm writing this email from my linux box without any > >> disconnecting > >> >>>> :-) > >> >>>> > > >> >>>> > According to John reply, setting lcp-echo-interval and > lcp-echo-failure > >> didn't > >> >>>> solve the problem..... > >> >>>> > Anyway, thanks again, John. > >> >>>> > > >> >>>> > Regarding Marvin response, it solved my problem, but the line "Init2 > = > >> ATQ0 > >> >>>> V1 E1 S0=0 &C1 &D2 +MS=34" should be changed to "Init2 = ATQ0 V1 E1 S0=0 > >> &C1 &D2 > >> >>>> +MS=V34" for my modem. > >> >>>> > > >> >>>> > Sincerely, > >> >>>> > Habib Seifzadeh > >> >>>> > > >> >>>> > > >> >>>> > ----- Original Message ---- > >> >>>> >> From: Marvin Stodolsky > >> >>>> >> To: Habib Seifzadeh > >> >>>> >> Cc: discuss@xxxxxxxxxxxxx > >> >>>> >> Sent: Wednesday, November 19, 2008 2:48:05 AM > >> >>>> >> Subject: Re: What's the best init string for noisy lines? > >> >>>> >> > >> >>>> >> Habib, > >> >>>> >> > >> >>>> >> At http://linmodems.technion.ac.il, there is a Post Install Howto > >> >>>> >> which may be useful. One potential fix is to reduce the default V92 > >> >>>> >> compression (+MS=92) which is poorly implemented at some IPs. Try > >> >>>> >> first V34 compression with: > >> >>>> >> Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +MS=34 > >> >>>> >> > >> >>>> >> If that allows your staying on line longer, try V90 with > >> >>>> >> Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +MS=90 > >> >>>> >> > >> >>>> >> MarvS > >> >>>> >> > >> >>>> >> On Tue, Nov 18, 2008 at 9:32 AM, Habib Seifzadeh > >> >>>> >> wrote: > >> >>>> >> > > >> >>>> >> > > >> >>>> >> > Hi all, > >> >>>> >> > > >> >>>> >> > Discussing the problem, I have three modems in my home; two of them > >> are > >> >>>> based > >> >>>> >> on Conexant chipset which work properly by linuxant driver and the > other > >> one > >> >>>> is > >> >>>> >> > Smartlink which works with sl-modem-daemon. So, I don't have any > >> >>>> >> > problem with installing the drivers. All of them connect to ISP and > >> >>>> >> > transmit info. Also, the OS is Ubuntu 8.10 > >> >>>> >> > > >> >>>> >> > The problem is that > >> >>>> >> > all of them disconnect from ISP frequently (About every 2 or 3 > >> minutes) > >> >>>> >> > when I'm in linux but none of them have such problem in Windows XP! > I > >> think > >> >>>> >> the reason is my noisy phone line but Windows XP knows how to recover > >> from > >> >>>> >> noises. > >> >>>> >> > > >> >>>> >> > I > >> >>>> >> > changed some settings like lcp-echo-failure and lcp-echo-interval > from > >> >>>> >> > /etc/ppp/options file. By increasing value of them, modem doesn't > >> >>>> >> > disconnect but no information is transferred 2 or 3 minutes after > >> >>>> >> > connecting and therefore I'm forced to disconnect manually. So, > they > >> >>>> >> > can't solve the main problem.... > >> >>>> >> > > >> >>>> >> > I > >> >>>> >> > guess the issue is solved by changing initial strings in dialing > >> >>>> >> > program configuaration files (e.g. /etc/wvdial.conf). After surfing > >> the > >> >>>> >> > net, I figured out that thare are some AT Commands in modems for > >> >>>> >> > recovering from noise. I think that Windows XP uses these commands > so > >> >>>> >> > that the modem doesn't disconnect at all. There are some pages > which > >> >>>> >> > describe AT Commanands but I couldn't find any one which solve the > >> >>>> >> > problem cleanly. Does anyone have any information about these AT > >> >>>> >> > Commands? > >> >>>> >> > > >> >>>> >> > By the way, I browsed the .inf file of one of my > >> >>>> >> > conexant modem's driver. I found this line: > >> >>>> >> > AT&FE0V1S0=0L3&C1&D2+MR=2;+DR=1;+ER=1;W2. When I use this > >> >>>> >> > command in wvdial.conf, the modem responds "Ok" but the problem > still > >> >>>> >> > remains... :-( > >> >>>> >> > > >> >>>> >> > Any help would be appreciated. > >> >>>> >> > Habib Seifzadeh > >> >>>> >> > > >> >>>> >> > > >> >>>> >> > > >> >>>> >> > > >> >>>> >> > > >> >>>> > > >> >>>> > > >> >>>> > > >> >>>> > > >> >>>> > > >> >>> > >> >>> > >> >>> > >> >>> > >> >>> > >> >> > >> > > > > > > > > > > >
