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Modems are crap - Mac Networking

Being used to DSL at home, I am reminded again as I travel how pathetic modems are. I don't mean bandwidth, although compared to my 1.5 Mb line at home a piddling 56K is real hard to adjust to. I mean the way they throw in the towel every time the phone line gets a little rough. Why is it that when I dial up my ISP's local port I can download my mail, surf the www, and use the usenet as one should be able to. But within 10 minute all comes to a grinding halt, as each app ...

  1. #1

    Default Modems are crap

    Being used to DSL at home, I am reminded again as I travel how pathetic
    modems are.

    I don't mean bandwidth, although compared to my 1.5 Mb line at home a
    piddling 56K is real hard to adjust to. I mean the way they throw in the
    towel every time the phone line gets a little rough.

    Why is it that when I dial up my ISP's local port I can download my mail,
    surf the www, and use the usenet as one should be able to. But within 10
    minute all comes to a grinding halt, as each app informs me that the "server
    can't be found", or other excuse.

    What has changed between my first few minutes of dial-up access and the last
    few? I doubt that each and every time this drama is played out during my
    travel day that the phone line improves and degrades with regularity.

    Can someone explain why the quality of the phone line -- marginal as it may
    be -- is just fine with the ISP's modem and mine when I first connect, but
    minutes later, all of a sudden it's not worthy of carrying a single bit?
    --
    DaveC
    net
    This is an invalid return address
    Please reply in the news group

    DaveC Guest

  2. #2

    Default Re: Modems are crap

    Don't know, it's probably aproblem on the server.. Some congestion or so..



     

    Peter Guest

  3. #3

    Default Re: Modems are crap

    DaveC <net> wrote:
     

    I wonder whether this has anything to do with the quality of the phone
    line. I found something very similar happening to me when I was using a
    dial-up connection. Often the first few minutes were OK, but after that
    things would start to go wrong and the connection would be lost.
    Dialling up again would establish a good connection, but that one again
    would go within a few minutes.

    Having noticed that this situation seemed usually to arise at the
    busiest times of the day, it made me wonder whether it might possibly be
    the result of deliberate actions by the ISP.

    I have heard people complaining about frequently getting engaged tones
    with some ISPs at busy times, and having to re-dial again and again
    before getting through. In my case, though, I *never* got the engaged
    tone - it always connected the first time. But there is a way that an
    ISP would be able to ensure that no-one ever got an engaged tone, even
    if there were not enough modems deployed to handle the load at busy
    times.

    What they could do is to continually monitor the modem usage, and if it
    began to approach 100% of the modems being busy, they could make random
    disconnections so as to bring the figure down. In this way they could
    quite truthfully claim "you will never get an engaged tone!".

    I'm sure it would be a simple matter to have all this carried out
    automatically, but am I being too cynical here? Or might they really be
    doing this?

    --
    Alec McKenzie
    com
    Alec Guest

  4. #4

    Default Re: Modems are crap

    In article <aaisp.net.uk>,
    Alec McKenzie <com> wrote:
     
    >
    > I wonder whether this has anything to do with the quality of the phone
    > line. I found something very similar happening to me when I was using a
    > dial-up connection. Often the first few minutes were OK, but after that
    > things would start to go wrong and the connection would be lost.
    > Dialling up again would establish a good connection, but that one again
    > would go within a few minutes.
    >
    > Having noticed that this situation seemed usually to arise at the
    > busiest times of the day, it made me wonder whether it might possibly be
    > the result of deliberate actions by the ISP.[/ref]

    Why blame the ISP instead of the carrier? The ISP has nothing to gain
    by dropping the connection, but I can't say the same for the phone
    company. 

    --
    There are 10 kinds of people in the world:
    those who understand binary, and those who don't.

    Tom Stiller

    PGP fingerprint = 5108 DDB2 9761 EDE5 E7E3
    7BDA 71ED 6496 99C0 C7CF
    Tom Guest

  5. #5

    Default Re: Modems are crap

    On Thu, 17 Jun 2004 16:42:42 -0500, Alec McKenzie wrote
    (in article <aaisp.net.uk>):
     
    >
    > I wonder whether this has anything to do with the quality of the phone
    > line. I found something very similar happening to me when I was using a
    > dial-up connection. Often the first few minutes were OK, but after that
    > things would start to go wrong and the connection would be lost.
    > Dialling up again would establish a good connection, but that one again
    > would go within a few minutes.
    >[/ref]

    Okay, since you used "dial-up" in the rooten old days, you
    remember that (if you're computer-old [grin] enough that
    since before high-speed (300 baud) modems were used, the INIT
    string has been the holy grail of the religious Modemers.

    How many INIT strings did you try?

    I can remember going through well over a hundred strings before I
    hit on the "right" one.

     

    It could surely be that the ISP doesn't have enough MODEMs but,
    if you're pretty generally actually getting through, the feed
    line could also be too limited in bandwidth.

    I would suspect that the ISP - if it offers both dial-up and
    cable/DSL - would not - for any reason - /ever/ do anything to
    purposely degrade the carrier as someone going from dial-up to
    cable/dsl would be likely to go with another ISP.

    And if they only offer dial-up, they would be, of course,
    slitting their corporate throat.
     

    I'd say you're /way/ too cynical.

    For the simple reason that it would be bad business.


    Gray Shockley
    -------------------------------------------
    For every complex problem there is an answer
    that is clear, simple, and wrong. - H. L. Mencken



    Gray Guest

  6. #6

    Default Re: Modems are crap

    DaveC <net> wrote:
     

    There is no reason to believe that "Modems are crap" on the basis of
    what you describe. I have found that modem connections can be extremely
    reliable. Whether using a dialup modem or DSL you can have the problems
    described ... almost always caused either by physical line problems or
    (most often) poor network performance of the ISP.

    --
    Adrian
    Adrian Guest

  7. #7

    Default Re: Modems are crap

    Gray Shockley wrote:
     

    I would have thought quite the opposite. If you want to push people onto
    ADSL, making the dialup service even crappier would be a good way of going
    about it.
     

    I'd agree.

    Pete
    Peter Guest

  8. #8

    Default Re: Modems are crap

    DaveC <net> wrote:
     

    Probably because the modems were too aggressive in negotiating
    connection speed or in increasing that speed when the phone line had
    little noise. Especially with earlier V.90 modems (a USR Courier and the
    internal modem in an older G4), I found it better to limit the speed in
    order to get a stable connection without constant speed renegotiations
    and retrains.

    Neill Guest

  9. #9

    Default Re: Modems are crap

    In article <1gfjtbv.bpn9pc1qd5w5cN%com>,
    com (Adrian W) wrote:
     
    >
    > There is no reason to believe that "Modems are crap" on the basis of
    > what you describe. I have found that modem connections can be extremely
    > reliable. Whether using a dialup modem or DSL you can have the problems
    > described ... almost always caused either by physical line problems or
    > (most often) poor network performance of the ISP.[/ref]

    Some modems do contribute to the problem by negotiating an initial
    connection speed that is too high to be sustained. When things settle
    out a bit, the modem should retrain to a lower speed. Retraining can
    take some time and cause things to grind to a halt for a time.

    Being solely on dial up, I do find that line conditions do change
    throughout the day. The best solution is to find the optimum speed that
    can normally be maintained and set your modem to connect at a rate no
    faster than that. If you travel to various cities, you might find a
    blanket rate of 36K to 40K might work well. It is relatively easy to
    edit the modem string to limit the connection speed.

    --
    Matt Broughton
    Only relatives are absolute.
    Matt Guest

  10. #10

    Default Re: Modems are crap

    Tom Stiller <net> wrote:
     
    >
    > Why blame the ISP instead of the carrier? The ISP has nothing to gain
    > by dropping the connection, but I can't say the same for the phone
    > company.[/ref]

    I would think the opposite.

    In the case I described (which was in the UK), the phone company gets
    revenue for each minute you are connected, and has nothing to gain by
    interrupting the connection. The ISP, on the other hand, is able to
    proclaim that you will never get an engaged tone from them.

    --
    Alec McKenzie
    com
    Alec Guest

  11. #11

    Default Re: Modems are crap

    DaveC <net> wrote: 

    I saw a problem with similar symptoms with regularity when I had
    a dial-up IP account with UUNET. I never learned out what the
    exact problem was, but the workaround I found was to lift the
    handset of my phone and scream into it. The noise would make the
    modems retrain and the bits would start flowing again.

    Kyle Guest

  12. #12

    Default Re: Modems are crap

    Peter Verdon wrote: 
    >
    >
    > I would have thought quite the opposite. If you want to push people onto
    > ADSL, making the dialup service even crappier would be a good way of going
    > about it.
    >

    >
    >
    > I'd agree.
    >[/ref]

    In a thread which mentions UK carriers, my experiences there say that
    you cannot be cynical enough.

    Paul Guest

  13. #13

    Default Re: Modems are crap

    DaveC <net> wrote:
     
     
     

    That is quite simple.

    Most dial-up modems are, for want of a better word, . They often
    lack good line filters, and want to re-train their connection whenever
    there is the slightest bit of interference. Internal modems (both the
    horrid Lucent winmodems and the silly things Apple put inside their
    Macs) are incredibly fussy, sensitive beasts.

    What happens is this.

    When your modem and the ISP's modem-bank start a connection, they have a
    little test to see how fast they can make the connection. Once they
    agree on a fast speed, they connect. Where the fun begins is when the
    customer's modem detects an increase in requests to have packets
    re-transmitted. To the modem, in its default state, this means that the
    line quality has dropped and it attempts to re-train the connection with
    the ISP's modem-bank. More often than not, though, this re-train process
    takes longer than what your OS expects, it doesn't detect the 'net on
    the other end (because the modem is busy re-training) so it assumes the
    connection has failed.

    Sometimes the modem does not correctly show that it has lost the link,
    forcing the user to manually disconnect and re-connect.

    To over-come this, it is possible to tell the modem to not retrain as
    often, and to also connect at a slower rate (the slower the maximum
    rate, the higher the chance of a sustained connection). It is also
    advisable to use the V92 protocol, as this has more resilience (better
    error detecting methods) to line-noise at higher speeds.

    The problem is exacerbated if the end-user's phone line is part of
    what's called a pair-gain -- two phone lines are multiplexed together
    (muxed) and send from the exchange down one copper pair, where they are
    split into two near the customer's home with a small demux circuit.
    Pair-gained lines have a maximum sustainable throughput of only 28k8.

    I myself live in an area where the line quality of the pairs is quite
    poor (and to be frank, most of Australia's copper network is in terrible
    condition). Until we went to DSL, there were three different computer /
    modems here that would hook to the net, an eMac, a PC with a Swann
    serial external and my old 9600 with a Hayes Accura 56 serial external.
    The eMac, even using V92, could *never* maintain a connection over 41k,
    but once I forced it to have 40k as a maximum try rate, it would hold a
    connection. The Swann external (which uses an old Conexant chipset)
    would reliably hold a 48k connection, using V90. The Hayes modem would
    happily sit on 52k for hours on end, and even hold the connection
    through someone inadvertently picking up the handset!

    In my many many years of cruising the net through modems, I've always
    found that the better the modem's line filtering circuitry, the better
    the connection. Internal modems have a simple R-C bridge and a line
    transformer the size of a pinky-nail, the Hayes has a whopping
    4cm-diameter transformer and an active bandpass filter circuit. Most
    ISPs that support dial-up will have in their resources a list of modem
    INIT strings that can force a users' modem to only connect at slower
    speeds, thus keeping the up-time higher. It is rare that a quality
    external modem will *ever* need to be slowed down, but the
    common-as-muck internal ones sold by all and sundry these days
    (including Apple) often require a slow-down string for something even
    *resembling* reliable operation.


    Geoffrey

    (remove EXCESS BAGGAGE to reply via mail)
    --
    WARNING: mail to this address will be auto-bounced if:
    (a) more than 10% original content appears before first quoted matter,
    (b) quoted material exceeds 75% of total message content, and/or
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    Geoffrey Guest

  14. #14

    Default Re: Modems are crap

    Interesting subject, a sore one with me!
    I would get disconecected from my dialup after a few seconds, or after a
    few minutes, even later on. I tried a clean instal of OS8, then an
    upgrade to OS9.1, then even a clean install of 9.1, same problems. My
    ISP says it's on my end. THEN, I got rid of the SupreExpress 56k modem
    and got a U.S.Robotics and things got better. I still get disconnects,
    but not as much. Sometimes its imediately after I get connected and
    start to get email. Sometimes is many minutes later while activley
    browsing. A few months ago I got a desktop G3/266. Well, I put that
    crappy old SupraExpress on the G3 just to have something.
    Well that darn thing is rock solid there.!!!. Seems to me it's a
    hardware issue between my ppc7500/100 and the G3/266.
    Any suggestions about that? My next step is a router so I can go high
    speed. I allreaday have an ethernet hup for my four macs.
    'glad tiddings' DaveC [/ref]
    Dave Guest

  15. #15

    Default Re: Modems are crap

    In article <supernews.com>,
    com (Kyle Jones) wrote: 

    LOL!!! That's priceless! I do tech support for an ISP. I wonder what
    reaction I'd get from a customer for suggesting this to them?

    Although I'm not doubting that it worked. :)

    --
    -=Elden=-
    http://www.w7ldn.com
    Elden Guest

  16. #16

    Default Re: Modems are crap

    -----BEGIN PGP SIGNED MESSAGE-----
    Hash: SHA1

    At 2004-06-18T00:56:46Z, Matt Broughton <com> writes:
     

    A quick-and-dirty workaround is to add three commas after the phone number
    you're dialing ("5551212,,,"). This causes the modem to wait for three
    seconds after the remote end answers before attempting to train up the
    connection. By this time, the window for establishing a fast-but-flaky
    connection has passed, so the modems can only handshake a slower-but-stable
    protocol. This will reduce your theoretical maximum speed, but the net
    result will be much faster since the connection won't be retraining the
    whole time.

    Let us know if that works for you.
    - --
    Kirk Strauser
    The Strauser Group
    Open. Solutions. Simple.
    http://www.strausergroup.com/
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