Re: PPP/modem connection dies when uploading

william.newman_at_airmail.net
Date: 07/15/05 

Date: 15 Jul 2005 08:12:10 -0700

I seem to have fixed my problem. My ISP (Internet America) wants PPP
clients to be hand-configured with "mru 552" and "mtu 552". These
settings are given in their web page
<http://support.airmail.net/connect/analog/cfgunixppp.php>; I don't
think that web page existed years ago when I initially set up my
connection, but I was able to surf to it from the boilerplate in the
"we have opened a trouble ticket" automated form letter that I was
sent when I sent email to their support department asking about the
problem. After switching to these recommended settings the
unreliability of my connection was reduced from unspeakably pathetic
(failing reliably after 100k bytes or so) to merely sad (20% infant
mortality, then mean time to failure 2M bytes or so). My big CVS
commit is done now, so my immediate needs were met despite sadness. In
the longer term, probably I want to find a less flaky ISP and perhaps
also switch to DSL and wireless, dropping my old phone modem in the
rubbish with the floppy disks and serial connections and whatnot.

The cfgunixppp.php page doesn't give any explanation of why the
settings are
needed, and I have no clue why the system doesn't seem to try to
negotiate them in the LCP setup logged in my original message. The
closest thing to a specific explanation I have is the "My PPP users
cannot upload to an FTP site; download works fine" entry in
"Compatible Systems - CSU/DSU and Modem Issues: Frequently Asked
Questions" at
<http://www.cisco.com/en/US/products/hw/routers/ps4081/products_qanda_item09186a0080094734.shtml>.
That's not much of an explanation, though; perhaps the general
explanation is just that key actors along the ISP and router-maker
foodchain choose to be more conservative than in what they accept than
the standard allows, and more liberal in what they send than the
standard allows.:-(

Relevant Pages

  • Re: Dialup connection and XP?
    ... Are you using the same settings as you did with Windows 98? ... you can contact your ISP and ask them the ... >it gets really aggrevating when I have to reconnect to get my connection ...
    (microsoft.public.windowsxp.help_and_support)
  • Re: PPP/modem connection dies when uploading
    ... My ISP wants PPP ... > connection, but I was able to surf to it from the boilerplate in the ... After switching to these recommended settings the ... > closest thing to a specific explanation I have is the "My PPP users ...
    (comp.os.linux.networking)
  • Re: PPP/modem connection dies when uploading
    ... My ISP wants PPP ... > connection, but I was able to surf to it from the boilerplate in the ... After switching to these recommended settings the ... > closest thing to a specific explanation I have is the "My PPP users ...
    (comp.os.linux.networking)
  • Re: MediaNet service with data card?
    ... ISP via dial-up. ... your PC software settings are correct, but your phone settings aren't, ... Communications Manager automatically set up the connection, ...
    (alt.cellular.cingular)
  • Re: Wi-Fi (Hotspot) Internet Connection on Pocket PC
    ... ISP, but the wi-fi connection at a cybercafe? ... > Work settings means connecting to your work network and seeing the ...
    (microsoft.public.pocketpc.wireless)