Basic questions about telecommunications

[Jeff Liebermann]

On Sat, 01 Jan 2011 18:13:15 -0800, David Nebenzahl
<nobody@but.us.chickens> wrote:

OK: Win2K SP 4; computer is (reading from the Windoze "System
Properties" dialog here as I can't remember the exact MB brand): "x86
Family 6 model 8" (Pentium IV???), running at, I believe, 700-something
MHz, 786 MB RAM. Yeah, not enough RAM,

768MB RAM is good enough for W2K. Of course, more would be better.

Family 6 Model 8 is a Pentium III mobile. 700Mhz sounds about right
but is rather slow. Any of the later PIII (non-M) Tualatin series
processors, that fit the socket, should work to give you a cheap speed
boost. Clock speeds to 1.33GHz.
<http://en.wikipedia.org/wiki/List_of_Intel_Pentium_III_microprocessors>

Partial list of processors:
Processor name Processor type
Intel Celeron Intel, x86 Family 6 Model 5
Intel Celeron Intel, x86 Family 6 Model 6
Intel Mobile Pentium III Intel, x86 Family 6 Model 8
Intel Pentium II Intel, x86 Family 6 Model 3
Intel Pentium II Intel, x86 Family 6 Model 5
Intel Pentium II Intel, x86 Family 6 Model 6
Intel Pentium III Intel, x86 Family 6 Model 7
Intel Pentium Pro Intel, x86 Family 6 Model 1
This will work on PIII and older motherboards, but will fail with
Core2Duo and other multicore processors:
<http://www.intel.com/support/processors/tools/frequencyid/sb/CS-007623.htm>

not very fast clock speed by
modren standards, but sheesh, should be able to keep up with a lousy 56K
modem even running full blast, dontcha think?

Sure. It can keep up with the modem, but perhaps not with the tons of
utilities, applications, drivers, and junk that are all running at the
same time. You'll lose a few clock cycles here and there. It won't
have much of an effect on download speed, but it *MIGHT* have an
effect on the consistency of any diagnostics running on top of the
download. If your modem happens to be a "softmodem" where all the
action ocurrs in software, then it will be even more sensitive to
unrelated activity.

Test application is Firefox, which is recent (not that it should matter,
right?): v3.6.8. The latest line-speed display I uploaded was while
downloading a PDF of a few megabytes.

The current version of Firefox is 3.6.13. To the best of my limited
knowledge, it does NOT have a built in download speed feature. You're
probably using a plugin or add-on, which was downloaded and installed.
Look under:
Tools -> Add-ons -> Extensions
for the name of the mystery performance monitoring application.

Anything else you want to know?

Nope. Just the name of the Firefox add-on. You supplied everything
else.

Can't tell you the model mfgr., except
that it's a cheapie I got at the local computer guy's store. Nothing
else fancy; no VPNs, PC-Anywhere, proxies, etc., etc.

Good point. I should have asked if you had any resident applications
that might interfere with the download, such as network shims, spyware
scanners, net proxy servers, Zone Alarm, or download managers.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[David Nebenzahl]

On 1/1/2011 7:25 PM Jeff Liebermann spake thus:

On Sat, 01 Jan 2011 18:13:15 -0800, David Nebenzahl
nobody@but.us.chickens> wrote:

Anything else you want to know?

Nope. Just the name of the Firefox add-on. You supplied everything
else.

What Firefox add-on? Didn't you read through the thread? The speed
reporting is from my firewall, Sygate Personal Firewall.

I just went to find their website and was dismayed to find out they've
been bought out by Norton (ugh): http://us.norton.com/sygate


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

 

[David Nebenzahl]

On 1/1/2011 4:19 PM Jeff Liebermann spake thus:

Incidentally, if you want to do useful performance measuring, with
clues as to what's going on behind the magic curtain, I suggest you
look at IPerf and JPerf.
http://openmaniak.com/iperf.php
http://code.google.com/p/xjperf/

Regarding that: I looked at the first site and am intrigued, but don't
understand something. I see you need a host and client to make this
work, which makes sense, and as you point out you might (or might not)
be able to use someone else's web-based host; but if not, what then? Can
you somehow set up both host and client on your computah and have the
packets make a "round trip"? (Although that would be a problem since I
notice my upload speeds are a lot slower than download.) How would I use
this to test my dial-up connection?

Also, do I want to test using TCP, UDP or both? Which are used when I
talk to my ISP?


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

 

[Jeff Liebermann]

On Sat, 01 Jan 2011 20:56:14 -0800, David Nebenzahl
<nobody@but.us.chickens> wrote:

On 1/1/2011 4:19 PM Jeff Liebermann spake thus:

Incidentally, if you want to do useful performance measuring, with
clues as to what's going on behind the magic curtain, I suggest you
look at IPerf and JPerf.
http://openmaniak.com/iperf.php
http://code.google.com/p/xjperf/

Regarding that: I looked at the first site and am intrigued, but don't
understand something. I see you need a host and client to make this
work, which makes sense, and as you point out you might (or might not)
be able to use someone else's web-based host; but if not, what then?

If you can't find an iperf server, you're stuck. I did some quick
Googling and couldn't find one that's publicly accessible.

I use IPerf and JPerf mostly for local wireless testing. I setup one
machine to act as a server, and test thruput via wireless under
various conditions. For testing a dialup connection, you would need
an IPerf server located at your ISP or somewhere on the internet. I
could set a temporary server here, at my house, but you would be
limited to my 384Kbit/sec DSL outgoing thruput. Probably good enough
for a dialup modem test. If you want to try that, please let me know.

Can
you somehow set up both host and client on your computah and have the
packets make a "round trip"? (Although that would be a problem since I
notice my upload speeds are a lot slower than download.) How would I use
this to test my dial-up connection?

No. It's not possible to use one computer for both a client and
server. Well, actually, I haven't tried it, but I suspect there will
be problems.

Also, do I want to test using TCP, UDP or both? Which are used when I
talk to my ISP?

Do TCP and forget about UDP for now. UDP testing is tricky and
sometimes results in bizarre results. TCP is reliable.



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Sat, 01 Jan 2011 20:50:40 -0800, David Nebenzahl
<nobody@but.us.chickens> wrote:

On 1/1/2011 7:25 PM Jeff Liebermann spake thus:

On Sat, 01 Jan 2011 18:13:15 -0800, David Nebenzahl
nobody@but.us.chickens> wrote:

Anything else you want to know?

Nope. Just the name of the Firefox add-on. You supplied everything
else.

What Firefox add-on? Didn't you read through the thread? The speed
reporting is from my firewall, Sygate Personal Firewall.

I just re-read all 10 of your messages in this thead and did not see
Sygate mentioned anywhere. Unless there was an article that didn't
appear on Giganews, I don't believe you mentioned that the graph came
from Sygate. You did mention that your "test application" was
Firefox, which is why I guessed that it was an add-on.

I just went to find their website and was dismayed to find out they've
been bought out by Norton (ugh): http://us.norton.com/sygate

The mediocre shall inherit the earth.

I was going to try and duplicate your setup, but with such an old
program, it's not going to happen. Sorry, but I've gone as far as I
can trying to explain why you're seeing those variations in speed.

Try this speed test:
<http://www.ispgeeks.com/wild/modules.php?name=CapacityTest>
It's not a nice neat graph as you were expecting, but it does give
repeatable tests from a well connected server. I'll see if I can find
another server that gives repeated data suitable for graphing.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Sun, 02 Jan 2011 00:03:46 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:

I'll see if I can find
another server that gives repeated data suitable for graphing.

This looks like a likely candidate:
<http://speedtestpro.net>
No clue if it works with W2K.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[David Nebenzahl]

On 1/2/2011 12:03 AM Jeff Liebermann spake thus:

Try this speed test:
http://www.ispgeeks.com/wild/modules.php?name=CapacityTest
It's not a nice neat graph as you were expecting, but it does give
repeatable tests from a well connected server. I'll see if I can find
another server that gives repeated data suitable for graphing.

I did try it. Interesting.

The test ran fine, but I was surprised to see the Java speed indicator
zoom up to ~700 kbps. I figured there was something perhaps bogus about
the speed test, but then I noticed that my Sygate monitor window also
showed speeds I'd never gotten before; the incoming (download) speed
went up to something like 120 K. Remember, my speeds usually bounce
between ~4 and ~6 K here.

So now I'm really confused. Are these transfer rates real? Remember, I'm
on a 56K modem.

Here's what they reported:

Your download capacity of 627 kbps is very low compared to most
broadband connections.*

Your upload capacity of 493 kbps is acceptable.

Your Quality of Service was measured at 30%, which shows that your
connection is unable to produce a constant stream of data.


* Except, of course, that I don't *have* a broadband connection!

Regarding your generous offer to perhaps set up a host for me to use to
check speeds, thanks, but remember this is just idle curiosity on my part.

If I ever have a real problem, maybe I'll take up your offer, and then
I'll really owe you one.


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

 

[Geoffrey S. Mendelson]

David Nebenzahl wrote:

The test ran fine, but I was surprised to see the Java speed indicator
zoom up to ~700 kbps. I figured there was something perhaps bogus about
the speed test, but then I noticed that my Sygate monitor window also
showed speeds I'd never gotten before; the incoming (download) speed
went up to something like 120 K. Remember, my speeds usually bounce
between ~4 and ~6 K here.

It's accurate. As someone else mentioned the modems break the data into packets
as it is sending the data down the line. The data in each packet is compressed
before being sent.

If the speed test were to send truely (or close to it) random packets of 1024
random 8 bit patterns, they would travel at less than rated speed down the line
because there is overhead in packetizing the data, adding checksums, etc.

If the speed test sends a simple pattern, constantly repeated, then the modems
will compress it to a very small string and send that string down the line,
recreating at the far end.

So by analyzing packet timestamps, you could see that a 1k packet of data
comes down the phone line to the modem at some enourmous rate of speed, say
100 times what the line actually handles, and by the time the next packet
arrives, there is a long delay.

So it would show up as a very fast line with lots of instability in performance,
which in this case it is.

In a case with a more random spread of data, it would perform more to your
expectations.

If you wish to have a real test of how well your line performs, find a site
that lets you download video files and time downloading one from start to
finish. As far as modem compression algorythms, video data is almost
100% random and that will remove that variable.

I also would check carefully what you are paying for the combination of
telephone usage ISP charges. I understand the US is a telecom company's
regulatory paradise, but in many places in the world, a cheap broadband
connection has been cheaper than a dial up for many years.

Geoff.

--
Geoffrey S. Mendelson N3OWJ/4X1GM
Those who cannot remember the past are condemned to misquote it.

 

[Dave Platt]

In article <4d2049a8$0$2417$822641b3@news.adtechcomputers.com>,
David Nebenzahl <nobody@but.us.chickens> wrote:

I did try it. Interesting.

The test ran fine, but I was surprised to see the Java speed indicator
zoom up to ~700 kbps. I figured there was something perhaps bogus about
the speed test, but then I noticed that my Sygate monitor window also
showed speeds I'd never gotten before; the incoming (download) speed
went up to something like 120 K. Remember, my speeds usually bounce
between ~4 and ~6 K here.

So now I'm really confused. Are these transfer rates real? Remember, I'm
on a 56K modem.

It may very well depend on what data they're sending in their test.

Most modem connections incorporate V.42bis data compression. The
sending modem compresses the data before transmitting it, and the
receiving modem decompresses after validating the CRCs in the data
frames.

The effectiveness of the data compression will depend on the data
being sent. HTML, other ASCII text, etc. will usually compress fairly
well (2:1 isn't uncommon), test data consisting of just a single byte
(e.g. zeros) repeated over and over will compress *extremely* well,
and pre-compressed binary data (e.g. .zip archives, .png and .jpeg and
..mpg files) usually won't compress at all.

If the upload and download speed test consists of TCP streams full of
zeros or some other constant data, you could be getting extremely high
compression ratios, and thus an artifically-high link throughput number.

--
Dave Platt <dplatt@radagast.org> AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
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