Router

Mike S wrote:
On 4/22/2018 2:42 AM, Paul wrote:
Mike S wrote:
On 4/21/2018 7:19 PM, Brian Gregory wrote:
On 18/04/2018 20:45, J. P. Gilliver (John) wrote:
In message , Brian
Gregory writes:
[]
A DSL modem that's switched on during daylight hours will often
have trouble continuing to work after dark. Switching it off and
on will get it going again.

Quite why they seem to be unable to make them so that they can
tell when the error rates are getting alarmingly high and
automatically recover on their own I don't know. But I've never
owned one that wasn't quite happy to just sit there for hours
reporting that it couldn't decode anything because there was too
much line noise for the speed it had initially negotiated when
conditions were better.

Even once a DSL modem has adjusted to the worst conditions
(usually night time) (by being switched off and on late at night)
it's likely it'll occasionally need switching off and on again,
maybe about once a week.

My cheap dynamode one, plugs away, day and night, very rarely
requiring any action on my part, and has for many years.

The ISP can limit the speed of the connection to make it more
reliable, or you can be so close to the exchange that you connect at
the max speed with lots of noise margin every time, or maybe you are
a long way from the exchange so that the troublesome higher
frequencies are virtually unused by the modem.

Exactly right, I worked for an ISP and we 'capped' (limited the
higher frequencies used by the connection) on problematic lines. In
our spare time we'd look for really slow connections (using a google
map that showed the connection speeds with different color markers
for speed ranges) and tried optimizing them for speed and stability.

That's a function of architecture though.

The old system used 18000 feet (or optionally 36000 feet) of
wire, to connect subscribers all the way back to the CO. On large
operations, the operator simply applied a "blanket cap" and didn't
give a crap. They took 8Mbit/sec max ADSL1 and sold a service
advertising 5Mbit/sec, and then capped it at 3Mbit/sec without
ever examining the statistics. They had the option of selling
it as 3Mbit/sec service, but they didn't, and... they got away
with it too.

The new system uses fiber-to-the-corner, the wire length (final hop)
is closer to 500 feet, as the wire runs from the box on the
corner of your street, to your house. And when they sell
you a service at "X", they actually deliver "X". Shurely
a miracle. No more cap, except for the cap of the
advertised service of X. No more laddling SNR margin
randomly and at their discretion, on top.

Some customers here, used to use DMT and file a trouble
ticket with the ISP, to "fix" the first case. And actually
have the link adjusted properly. Some of those people,
hanging out at DSLReport :-)

There are still areas of the country operating the old
way. And the operator in that case, has absolutely no plan
to fix any infrastructure. It'll take a slap from the government
to keep the physical plant functional. There's a guy in the WinXP
group who is getting the old fashioned "service", complete
with "horse, buggy, and excuses".

Paul

We're getting fiber installed (Santa Cruz, CA) in the city center areas
now. I stopped using DSL because where I live, even though I'm less than
.75 mile from the CO and got great DSL speeds, the phone wiring is so
old that when it rained I saw frequent slowdowns, lost conn's, or loss
of service, no problems with cable. The fiber will be a lot faster for
the same cost with much lower latency, something like 2 mS if I
understand it correctly, so that will be great and probably feel more
responsive, click and stuff happens faster. The ISP includes a required
fiber-modem rental service where they can monitor or control the modem.

The typical last-hop on some of this fiber stuff, is "PON".

https://en.wikipedia.org/wiki/Passive_optical_network

At the head end, one laser is split 32 ways, by a fiber splitter.
Two colors of light are used, for TX and RX. And this allows each
subscriber to only need one screw-in optical connector in the
garage. Since the two colors of light are independent, it
operates full duplex.

When they share like that, some protocol has to decide which
unit transmits next.

Using schemes like that is cheaper, for the access device at the
end of the street, but as you'd imagine, there are some fault
scenarios where 32 customers will lose service at the same time.

I had a problem with a scheme like that, at work. A shared media
network, where I hadn't put a lot of thought into the reliability
aspects. Then one day, a client unit goes nuts, and stops following
the access protocol. Which causes the whole network to go down.
That's when it occurred to me, exactly how many silicon
chips were in a single fault group. Doh! :-) I don't think anyone
in the chain of command was surprised by the result, probably
more surprised that the Devils Dice had been thrown to give
them a demo of such :-) Your fiber device is likely to be
*much* more reliable than that :-) (Crosses fingers, etc.)

They shouldn't be running "private" fiber to each subscriber,
because that would raise the installed per-channel cost. And
make the box at the end of the street, that much bigger. They
might do it that way some day, but individual fibers is
pretty expensive per channel.

And why did they pick 32 ? The optical loss goes up as the
number of channels increases. Notice how in the Specification
table for this device, for each doubling in subscribers, there's
3dB more loss. Eventually, the laser "won't make its way to the
other end" through that thing. The light is split equally from
the head end, into the fibers. There is likely to be more
loss through the splitter, than through any other component
leading to your house. The splitter is inside the box at the
end of your street.

https://www.fs.com/products/11948.html

1X2 1X4 1X8 1X16 1X32 1X64
4.1 7.2 10.4 13.4 16.4 19.9 dB insertion loss

And I have no idea what they're telling you in terms of
"available" or "guaranteed" bandwidth with such solutions.
The incoming fiber is being split 32 ways, so you get 1/32
of whatever rate that fiber runs at (worst case).

As you can tell, I'd be "full of questions" when the
installer shows up :-) I love stuff like this. Especially
when it's cheaply made and so clever.

Customers absolutely hate statistical multiplexing. I'll
never forget the "angry mob" around the Rogers booth at
the Mall, when the first cable system failed to deliver
on speed. And that's because the provider didn't have nearly
enough equipment in the core of the network, for the
number of subscribers. The mob was so angry, Rogers
closed the booth :-) So people wouldn't mill about
like angry bees. That's fixed now, and the cable network
here is every bit as competitive as any other provider.
No more angry mobs need be formed. The lesson to be learned
from this, is if you want to be a "slimeball ISP", *don't*
set up a booth at the Mall :-) Just some friendly advice.

Paul

On 22/04/2018 03:19, Brian Gregory wrote:
snip
The ISP can limit the speed of the connection to make it more reliable,
or you can be so close to the exchange that you connect at the max speed
with lots of noise margin every time, or maybe you are a long way from
the exchange so that the troublesome higher frequencies are virtually
unused by the modem.

What speed do you get?


I should add that it also makes a big difference if your line runs most
of the way back to the exchange underground, or if it's up on when we in
the UK call telegraph poles some of the way. Underground is probably
typically best but proximity to lots of other lines in a multicore
underground cable can also be source of interference.

--

Brian Gregory (in England).

On 4/22/2018 5:07 AM, Paul wrote:
Mike S wrote:
On 4/22/2018 2:42 AM, Paul wrote:
Mike S wrote:
On 4/21/2018 7:19 PM, Brian Gregory wrote:
On 18/04/2018 20:45, J. P. Gilliver (John) wrote:
In message , Brian
Gregory writes:
[]
A DSL modem that's switched on during daylight hours will often
have trouble continuing to work after dark. Switching it off and
on will get it going again.

Quite why they seem to be unable to make them so that they can
tell when the error rates are getting alarmingly high and
automatically recover on their own I don't know. But I've never
owned one that wasn't quite happy to just sit there for hours
reporting that it couldn't decode anything because there was too
much line noise for the speed it had initially negotiated when
conditions were better.

Even once a DSL modem has adjusted to the worst conditions
(usually night time) (by being switched off and on late at night)
it's likely it'll occasionally need switching off and on again,
maybe about once a week.

My cheap dynamode one, plugs away, day and night, very rarely
requiring any action on my part, and has for many years.

The ISP can limit the speed of the connection to make it more
reliable, or you can be so close to the exchange that you connect
at the max speed with lots of noise margin every time, or maybe you
are a long way from the exchange so that the troublesome higher
frequencies are virtually unused by the modem.

Exactly right, I worked for an ISP and we 'capped' (limited the
higher frequencies used by the connection) on problematic lines. In
our spare time we'd look for really slow connections (using a google
map that showed the connection speeds with different color markers
for speed ranges) and tried optimizing them for speed and stability.

That's a function of architecture though.

The old system used 18000 feet (or optionally 36000 feet) of
wire, to connect subscribers all the way back to the CO. On large
operations, the operator simply applied a "blanket cap" and didn't
give a crap. They took 8Mbit/sec max ADSL1 and sold a service
advertising 5Mbit/sec, and then capped it at 3Mbit/sec without
ever examining the statistics. They had the option of selling
it as 3Mbit/sec service, but they didn't, and... they got away
with it too.

The new system uses fiber-to-the-corner, the wire length (final hop)
is closer to 500 feet, as the wire runs from the box on the
corner of your street, to your house. And when they sell
you a service at "X", they actually deliver "X". Shurely
a miracle. No more cap, except for the cap of the
advertised service of X. No more laddling SNR margin
randomly and at their discretion, on top.

Some customers here, used to use DMT and file a trouble
ticket with the ISP, to "fix" the first case. And actually
have the link adjusted properly. Some of those people,
hanging out at DSLReport :-)

There are still areas of the country operating the old
way. And the operator in that case, has absolutely no plan
to fix any infrastructure. It'll take a slap from the government
to keep the physical plant functional. There's a guy in the WinXP
group who is getting the old fashioned "service", complete
with "horse, buggy, and excuses".

Â*Â*Â* Paul

We're getting fiber installed (Santa Cruz, CA) in the city center
areas now. I stopped using DSL because where I live, even though I'm
less than .75 mile from the CO and got great DSL speeds, the phone
wiring is so old that when it rained I saw frequent slowdowns, lost
conn's, or loss of service, no problems with cable. The fiber will be
a lot faster for the same cost with much lower latency, something like
2 mS if I understand it correctly, so that will be great and probably
feel more responsive, click and stuff happens faster. The ISP includes
a required fiber-modem rental service where they can monitor or
control the modem.

The typical last-hop on some of this fiber stuff, is "PON".

https://en.wikipedia.org/wiki/Passive_optical_network

At the head end, one laser is split 32 ways, by a fiber splitter.
Two colors of light are used, for TX and RX. And this allows each
subscriber to only need one screw-in optical connector in the
garage. Since the two colors of light are independent, it
operates full duplex.

When they share like that, some protocol has to decide which
unit transmits next.

Using schemes like that is cheaper, for the access device at the
end of the street, but as you'd imagine, there are some fault
scenarios where 32 customers will lose service at the same time.

I had a problem with a scheme like that, at work. A shared media
network, where I hadn't put a lot of thought into the reliability
aspects. Then one day, a client unit goes nuts, and stops following
the access protocol. Which causes the whole network to go down.
That's when it occurred to me, exactly how many silicon
chips were in a single fault group. Doh! :-) I don't think anyone
in the chain of command was surprised by the result, probably
more surprised that the Devils Dice had been thrown to give
them a demo of such :-) Your fiber device is likely to be
*much* more reliable than that :-) (Crosses fingers, etc.)

They shouldn't be running "private" fiber to each subscriber,
because that would raise the installed per-channel cost. And
make the box at the end of the street, that much bigger. They
might do it that way some day, but individual fibers is
pretty expensive per channel.

And why did they pick 32 ? The optical loss goes up as the
number of channels increases. Notice how in the Specification
table for this device, for each doubling in subscribers, there's
3dB more loss. Eventually, the laser "won't make its way to the
other end" through that thing. The light is split equally from
the head end, into the fibers. There is likely to be more
loss through the splitter, than through any other component
leading to your house. The splitter is inside the box at the
end of your street.

https://www.fs.com/products/11948.html

Â*Â* 1X2Â*Â* 1X4Â*Â* 1X8Â*Â*Â* 1X16Â*Â* 1X32Â*Â* 1X64
Â*Â* 4.1Â*Â* 7.2Â*Â* 10.4Â*Â* 13.4Â*Â* 16.4Â*Â* 19.9Â*Â* dB insertion loss

And I have no idea what they're telling you in terms of
"available" or "guaranteed" bandwidth with such solutions.
The incoming fiber is being split 32 ways, so you get 1/32
of whatever rate that fiber runs at (worst case).

As you can tell, I'd be "full of questions" when the
installer shows up :-) I love stuff like this. Especially
when it's cheaply made and so clever.

Customers absolutely hate statistical multiplexing. I'll
never forget the "angry mob" around the Rogers booth at
the Mall, when the first cable system failed to deliver
on speed. And that's because the provider didn't have nearly
enough equipment in the core of the network, for the
number of subscribers. The mob was so angry, Rogers
closed the booth :-) So people wouldn't mill about
like angry bees. That's fixed now, and the cable network
here is every bit as competitive as any other provider.
No more angry mobs need be formed. The lesson to be learned
from this, is if you want to be a "slimeball ISP", *don't*
set up a booth at the Mall :-) Just some friendly advice.

Â*Â* Paul

Very interesting Paul, I had no idea how the network worked and I had
wondered about how they'd set it up, thanks. I no longer work for the
ISP so here's hoping, lol.

In message , Brian
Gregory writes:
On 18/04/2018 20:45, J. P. Gilliver (John) wrote:
In message , Brian
Gregory writes:
[]
A DSL modem that's switched on during daylight hours will often have
trouble continuing to work after dark. Switching it off and on will
get it going again.

Quite why they seem to be unable to make them so that they can tell
when the error rates are getting alarmingly high and automatically
recover on their own I don't know. But I've never owned one that
wasn't quite happy to just sit there for hours reporting that it
couldn't decode anything because there was too much line noise for
the speed it had initially negotiated when conditions were better.

Even once a DSL modem has adjusted to the worst conditions (usually
night time) (by being switched off and on late at night) it's likely
it'll occasionally need switching off and on again, maybe about once


My cheap dynamode one, plugs away, day and night, very rarely
requiring any action on my part, and has for many years.

The ISP can limit the speed of the connection to make it more reliable,
or you can be so close to the exchange that you connect at the max
speed with lots of noise margin every time, or maybe you are a long way
from the exchange so that the troublesome higher frequencies are
virtually unused by the modem.

About 1.2 miles https://goo.gl/maps/go9J6ZJXyjF2, I _think_ with no
cabinets in between. (I've just googlewalked it, though they could be
hidden under/behind something.)

What speed do you get?

Around 11 down, 1 up, according to
https://www.broadbandspeedchecker.co.uk/?&again. More than adequate for
my needs: YouTube and other videos, even HD, download faster than I can
view them, and there's only me in this household, so I can't think of
other things I might want that needs more. (OK, _huge_ downloads - i. e.
in the several G - would take a long time, but I very rarely do those.
And could leave them running while I do something else.)
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

Wisdom is the ability to cope. - the late (AB of C) Michael Ramsey,
quoted by Stephen Fry (RT 24-30 August 2013)

J. P. Gilliver (John) wrote:
In message , Brian
Gregory writes:
On 18/04/2018 20:45, J. P. Gilliver (John) wrote:
In message , Brian
Gregory writes:
[]
A DSL modem that's switched on during daylight hours will often have
trouble continuing to work after dark. Switching it off and on will
get it going again.

Quite why they seem to be unable to make them so that they can tell
when the error rates are getting alarmingly high and automatically
recover on their own I don't know. But I've never owned one that
wasn't quite happy to just sit there for hours reporting that it
couldn't decode anything because there was too much line noise for
the speed it had initially negotiated when conditions were better.

Even once a DSL modem has adjusted to the worst conditions (usually
night time) (by being switched off and on late at night) it's likely
it'll occasionally need switching off and on again, maybe about once

My cheap dynamode one, plugs away, day and night, very rarely
requiring any action on my part, and has for many years.

The ISP can limit the speed of the connection to make it more
reliable, or you can be so close to the exchange that you connect at
the max speed with lots of noise margin every time, or maybe you are a
long way from the exchange so that the troublesome higher frequencies
are virtually unused by the modem.

About 1.2 miles https://goo.gl/maps/go9J6ZJXyjF2, I _think_ with no
cabinets in between. (I've just googlewalked it, though they could be
hidden under/behind something.)

What speed do you get?

Around 11 down, 1 up, according to
https://www.broadbandspeedchecker.co.uk/?&again. More than adequate for
my needs: YouTube and other videos, even HD, download faster than I can
view them, and there's only me in this household, so I can't think of
other things I might want that needs more. (OK, _huge_ downloads - i. e.
in the several G - would take a long time, but I very rarely do those.
And could leave them running while I do something else.)

And what "plan" did they sell you ?

Is it a plan for 11 that delivers 11 ?

There's a curve on this page, that shows what a typical
result should be. 1930 meters is "18000Kbps down" on ADSL2+.
That's if there were no other constraints in place. Since
that is a line rate, the "Goodput" is the rate that results
when the PPPOE overhead is removed.

https://www.internode.on.net/residen...d/performance/

https://www.internode.on.net/media/i...sl2-dist07.jpg

Paul

In message , Paul
writes:
J. P. Gilliver (John) wrote:
In message , Brian
Gregory writes:
On 18/04/2018 20:45, J. P. Gilliver (John) wrote:
In message , Brian
Gregory writes:
[]
A DSL modem that's switched on during daylight hours will often
have trouble continuing to work after dark. Switching it off and
on will get it going again.

Quite why they seem to be unable to make them so that they can
tell when the error rates are getting alarmingly high and
automatically recover on their own I don't know. But I've never
owned one that wasn't quite happy to just sit there for hours
reporting that it couldn't decode anything because there was too
much line noise for the speed it had initially negotiated when conditions were better.

Even once a DSL modem has adjusted to the worst conditions
(usually night time) (by being switched off and on late at night)
it's likely it'll occasionally need switching off and on again,
maybe about once

My cheap dynamode one, plugs away, day and night, very rarely
requiring any action on my part, and has for many years.

The ISP can limit the speed of the connection to make it more
reliable, or you can be so close to the exchange that you connect at
the max speed with lots of noise margin every time, or maybe you are
a long way from the exchange so that the troublesome higher
frequencies are virtually unused by the modem.
About 1.2 miles https://goo.gl/maps/go9J6ZJXyjF2, I _think_ with no
cabinets in between. (I've just googlewalked it, though they could be
hidden under/behind something.)

What speed do you get?

Around 11 down, 1 up, according to
https://www.broadbandspeedchecker.co.uk/?&again. More than adequate
for my needs: YouTube and other videos, even HD, download faster than
I can view them, and there's only me in this household, so I can't
think of other things I might want that needs more. (OK, _huge_
downloads - i. e. in the several G - would take a long time, but I
very rarely do those. And could leave them running while I do something else.)

And what "plan" did they sell you ?

Is it a plan for 11 that delivers 11 ?

I think it was "up to 8" when I first took it; when I first measured it,
it was 5-6, which was good then. I don't know when it went up - possibly
when they went from ADSL to ADSL+ (or is it ADSL2+). I don't remember
being conscious of them specifically saying they'd raised it, but since
even 5 was enough for me, I probably wouldn't have noticed. I was
slightly surprised when I measured it sometime in the last week or so (a
regular correspondent asked me) and found it had gone up to 11.
[]
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

Beauty is in the eye of the beer holder...

J. P. Gilliver (John) wrote:


I think it was "up to 8" when I first took it; when I first measured it,
it was 5-6, which was good then. I don't know when it went up - possibly
when they went from ADSL to ADSL+ (or is it ADSL2+). I don't remember
being conscious of them specifically saying they'd raised it, but since
even 5 was enough for me, I probably wouldn't have noticed. I was
slightly surprised when I measured it sometime in the last week or so (a
regular correspondent asked me) and found it had gone up to 11.

Whatever you do, don't phone up and ask :-)

Or they'll turn it down again.

Paul

In message , Paul
writes:
J. P. Gilliver (John) wrote:

I think it was "up to 8" when I first took it; when I first measured
it, it was 5-6, which was good then. I don't know when it went up -
possibly when they went from ADSL to ADSL+ (or is it ADSL2+). I don't
remember being conscious of them specifically saying they'd raised
it, but since even 5 was enough for me, I probably wouldn't have
noticed. I was slightly surprised when I measured it sometime in the
last week or so (a regular correspondent asked me) and found it had
gone up to 11.

Whatever you do, don't phone up and ask :-)

Or they'll turn it down again.

Paul

(-:

I've just had connection fail two or three times in a row, so I've
switched from my trusty dynamode MoDem/router/wifi to the (second-hand)
Netgear one I acquired recently (a 3300, I think). Checking with that,
the speed is the same, ~11 down 1 up (wifi or cable-connected, made no
difference). I _suspect_ there's nothing wrong with the dynamode, since
I had a similar failure the other day - I think it's the line or
exchange. I'll stay on the Netgear for a few days.
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

Never. For me, there has to be a meaning. There's not much meaning in eating
bugs. - Darcey Bussell (on whether she'd appear on /I'm a Celebrity/), in RT
2015/11/28-12/4