19 Jul
2001
19 Jul
'01
12:25 p.m.
Chuck McManis <cmcmanis@mcmanis.com>@classiccmp.org on 07/19/2001 03:21:47
PM
Please respond to classiccmp(a)classiccmp.org
Sent by: owner-classiccmp(a)classiccmp.org
To: classiccmp(a)classiccmp.org
cc:
Subject: Re: OT: DSL Woes (was RE: Plato terminal
At 01:31 PM 7/19/01 -0500, you wrote:
I'm troubled by the desire of companies to provide
mission critical
services
over consumer quality telecommunication and computer
equipment.
And you wonder why they went out of business? DSL can be much more reliable
than Cable Modems but it does have to be installed properly, and you need
to have the correct filter at the junction box to prevent interference with
line noise.
--Chuck
--------------------------------------------------------
Very true. Qwest (Formerly U.S.Worst,er West) in Cedar Rapids Iowa has
fairly decent DSL. They don't futz around with your computer like the @Home
cable modem folks do. I've had 256k DSL for about 9 months now and had
about 37 minutes of down time. (~20 min, and then ~17 min a couple months
later) Of course I live in a bedroom community about 5 blocks from the
TelCo switch. <grin>
My only gripe is that the Cisco 675 DSL router/modem they sold me MUST be
in routing mode, not bridging mode, and it does not have the capability to
do port forwarding. <sigh> So you can't run a server to save your soul.
- M.S.
19 Jul
19 Jul
1:55 p.m.
On Thu, 19 Jul 2001 mjsnodgr(a)rockwellcollins.com wrote:
I've had 256k DSL for about 9 months now
Is 256 kbps common for DSL or cable?
A network admin at the local cable company here (who handles my cable
modem service) told me that their infrastructure can do 10 Mbps to each
modem, but that the software in the modem was configured to limit that to
2 Mbps. I don't know if the software limit story is true, but I can vouch
for the 2 Mbps effective rate. I've had FTP transfers in excess of 200
KBps before.
had about 37 minutes of down time.
I've had more than that. Sometimes it happens several times per week, but
there have also been periods of several months without problems. Only one
outage has lasted over 30 minutes. It's been good enough for me to run
this mail server on it.
Speaking of running servers: my cable company supports it. I've never
came out and asked them directly, but all the evidence is there. There
are explicit provisions in the service agreement against running servers
_for_other_parties_, but no other mention. IPs are assigned via DHCP (I
probably ought to ask if static IPs are available), but you always get the
same IP until you change NICs. Finally, I've been running a mail server
over my link for a while, and my logs show that the cable company has
tested it for open relaying (which I don't do) several times. I have
never gottan a call from them asking me to not have the server up.
--
Jeffrey S. Sharp
jss(a)ou.edu
2:25 p.m.
There's quite a bit of competition, at least rhetorically, between QWEST, our
local phone service provider, and AT&T, which is the local cable company. Both
offer "high-bandwidth" (DSL/Cable) internet service. The party line from
AT&T
is that they offer 256Kb up and down, while QWEST guarantees that you get at
least that. I have DSL from QWEST and they tell me (via their router, which
could easily lie) that I normally have 640Kb down and 272 up. That speed isn't
reflected in my transfer speeds, however.
I seem to remember reading that the former RBOC's are required to provide a 256k
minimal transfer rate in either direction, while the cable service providers
have more latitude. Everyone I know who's got/had the AT&T cable modem service
has had lower slower transfer rates. My understanding is that AT&T is
provisioned such that they can provide the full 256Kb to one block (whatever
that means, but presumably a city-block, since that's how they're physically
structured) and that's what the customers on that block have to share. I find
that a little hard to swallow, but it's possible, since these companies are run
by bean-counters.
Though the statistics my DSL modem software provide suggest I receive lots of
bandwidth, my transfer speeds vary widely. I have made a few cursory tests, and
found on one occasion, that when I used my notebook via dialup on the voice
line, at 56Kb, I got faster transfer (concurrent transfer of the same file from
the same place took WAY less time) than concurrently and through the same ISP
via my DSL connection. Weird!
Dick
----- Original Message -----
From: "Jeffrey S. Sharp" <jss(a)subatomix.com>
To: <classiccmp(a)classiccmp.org>
Sent: Thursday, July 19, 2001 4:55 PM
Subject: Re: OT: DSL Woes
On Thu, 19 Jul 2001 mjsnodgr(a)rockwellcollins.com
wrote:
I've had 256k DSL for about 9 months now
Is 256 kbps common for DSL or cable?
A network admin at the local cable company here (who handles my cable
modem service) told me that their infrastructure can do 10 Mbps to each
modem, but that the software in the modem was configured to limit that to
2 Mbps. I don't know if the software limit story is true, but I can vouch
for the 2 Mbps effective rate. I've had FTP transfers in excess of 200
KBps before.
had about 37 minutes of down time.
I've had more than that. Sometimes it happens several times per week, but
there have also been periods of several months without problems. Only one
outage has lasted over 30 minutes. It's been good enough for me to run
this mail server on it.
Speaking of running servers: my cable company supports it. I've never
came out and asked them directly, but all the evidence is there. There
are explicit provisions in the service agreement against running servers
_for_other_parties_, but no other mention. IPs are assigned via DHCP (I
probably ought to ask if static IPs are available), but you always get the
same IP until you change NICs. Finally, I've been running a mail server
over my link for a while, and my logs show that the cable company has
tested it for open relaying (which I don't do) several times. I have
never gottan a call from them asking me to not have the server up.
--
Jeffrey S. Sharp
jss(a)ou.edu
20 Jul
20 Jul
8:46 a.m.
I seem to remember reading that the former RBOC's
are required to provide a 256k
minimal transfer rate in either direction, while the cable service providers
have more latitude. Everyone I know who's got/had the AT&T cable modem service
has had lower slower transfer rates. My understanding is that AT&T is
provisioned such that they can provide the full 256Kb to one block (whatever
that means, but presumably a city-block, since that's how they're physically
structured) and that's what the customers on that block have to share. I find
that a little hard to swallow, but it's possible, since these companies are run
by bean-counters.
Yep, I generally get about 240 kbps upload from my cable modem. The 4-6 Mbps
typical download makes up for the lost 16 kbps. Biggest problem I have with
my cable modem is latency which can be 100 to 300 ms (round trip) at times. It
can be annoying for shell access. Then again, I still remember getting
30000 ms latency the consoles of overworked unix machines as an undergrad,
so I can cope
Though the statistics my DSL modem software provide
suggest I receive lots of
bandwidth, my transfer speeds vary widely. I have made a few cursory tests, and
found on one occasion, that when I used my notebook via dialup on the voice
line, at 56Kb, I got faster transfer (concurrent transfer of the same file from
the same place took WAY less time) than concurrently and through the same ISP
via my DSL connection. Weird!
Transfer times are dominated by bottlenecks that could be anywhere in between
you and the source. All bandwidth is shared bandwidth. Your 56k modem
connected to another modem on the other side of the DSL bottleneck, meaning
a bunch of DSL users were sharing a small pipe somewhere.
Last time I checked, ISP's were paying about $600/mo/Mbps for
connectivity. That means if they've got 100Mbps to the backbone, they
need to share those costs among 2000 users at $30/mo before they can
even think about making a profit (making the bad assumption no other
costs are involved). In other words, your ISP is betting that
your monthly average transfer rate is substantially less than 50 kbps. Ever
wonder why DSL and cable providers get upset when people paying residential
rates try to set up a server?
It also means that when all 2000 users try to download porn simultaneously
their data rates are going to drop to <50 kbps.
Of course the same is true at both ends of a connection.
Eric
19 Jul
19 Jul
2:28 p.m.
On Thu, 19 Jul 2001, Jeffrey S. Sharp wrote:
When I first had mine installed the downtime was extensive each week.
More recently availability has been good, but the usenet news server has
sucked. Most recently it has been okay too.
On Thu, 19 Jul 2001 mjsnodgr(a)rockwellcollins.com
wrote:
Once you have firgured out your cable modem's IP address from its DHCP
or ARP broadcasts, there is a snmp mib where you can see what you are
limited to. My roadrunner cable modem has 384k upload 2m download
transmission.127.1.1.3.1.3.1 = 384000
transmission.127.1.1.3.1.5.1 = 2000000
Originally the roadrunner folks had their configurations wrong and various
broadcasts were entering the network that weren't supposed to be there
unlike the DHCP or ARP). I was getting broadcasts for Novell get nearest
servers, HP jet direct printservers and other oddities on other people's
networks. For a while I had linux latd misconfigured to be going out my
eth0 by mistake and I am sure that others were getting my LAT service
broadcasts. :-)
I've had 256k DSL for about 9 months now
Is 256 kbps common for DSL or cable?
A network admin at the local cable company here (who handles my cable
modem service) told me that their infrastructure can do 10 Mbps to each
modem, but that the software in the modem was configured to limit that to
2 Mbps. I don't know if the software limit story is true, but I can vouch
for the 2 Mbps effective rate. I've had FTP transfers in excess of 200
KBps before. had about 37 minutes of down time.
I've had more than that. Sometimes it happens several times per week, but
there have also been periods of several months without problems. Only one
outage has lasted over 30 minutes. It's been good enough for me to run
this mail server on it.
Speaking of running servers: my cable company supports
it. I've never
came out and asked them directly, but all the evidence is there. There
are explicit provisions in the service agreement against running servers
_for_other_parties_, but no other mention. IPs are assigned via DHCP (I
probably ought to ask if static IPs are available), but you always get the
same IP until you change NICs. Finally, I've been running a mail server
over my link for a while, and my logs show that the cable company has
tested it for open relaying (which I don't do) several times. I have
never gottan a call from them asking me to not have the server up.
I have had similar experiences. I use /etc/hosts.allow /etc/hosts.deny on
my Linux box to limit accessibility for everything but ssh to my work
domain. I see on the local homepage that various folks run servers for
various things from gaming to backyard video cameras.
The local phone company has the DSL infrastructure in place for itself (I
have been in the frame relay switchroom where the DSL stuff hooks to their
FR network and all the parts are there ready to go) but won't deploy it
due to internal political reasons. There are one or more alternate
providers in the area, at least one of which was affected by the large DSL
company which went out of business several months ago.
--
Jeffrey S. Sharp
jss(a)ou.edu
--
2:17 p.m.
On Thu, 19 Jul 2001 mjsnodgr(a)rockwellcollins.com
wrote:
When the source can do it, I get 168k bytes per second with Roadrunner
cable modem (thats about 1.5 Mbps).
The real catch with DSL is that garden variety the downlink speed is very
good, and uplink may be only 7k bytyes per second, which isn't shiningly
better than 56k modems.
I've had 256k DSL for about 9 months now
Is 256 kbps common for DSL or cable?
A network admin at the local cable company here (who handles my cable
modem service) told me that their infrastructure can do 10 Mbps to each
modem, but that the software in the modem was configured to limit that to
2 Mbps. I don't know if the software limit story is true, but I can vouch
for the 2 Mbps effective rate. I've had FTP transfers in excess of 200
KBps before. 
19 Jul
19 Jul
8:35 p.m.
On Thu, 19 Jul 2001 mjsnodgr(a)rockwellcollins.com wrote:
My only gripe is that the Cisco 675 DSL router/modem
they sold me MUST be
in routing mode, not bridging mode, and it does not have the capability to
do port forwarding. <sigh> So you can't run a server to save your soul.
You just need new firmware for your modem :) Go to:
http://www.users.qwest.net/~rlutton/ADSL
I'm running 2.3.5.012 and it has NAT and everything! I supply
FTP to a limited number of people for pickups and dropoffs, and
regularly telnet in from work to read email... I haven't yet
set up a web server, but once I get the CGI to read the cameras
I'll have un-real time access to internal and external security
cameras.... (and the idiot who lets his dog IBM in my yard will
get a visit from animal control)...
Clint
9:20 p.m.
regularly telnet in from work to read email... I
haven't yet
set up a web server, but once I get the CGI to read the cameras
I'll have un-real time access to internal and external security
cameras.... (and the idiot who lets his dog IBM in my yard will
get a visit from animal control)...
Why not save a frame of video to the hard drive every few seconds, then
watch the file at night?
8405
days inactive
8406
days old
8 comments
7 participants
participants (7)
-
edick＠idcomm.com -
jss＠subatomix.com -
korpela＠ellie.ssl.berkeley.edu -
mikeford＠socal.rr.com -
mjsnodgr＠rockwellcollins.com -
thompson＠mail.athenet.net -
vaxman＠qwest.net