tony sayer wrote:
In article , chris French
scribeth thus
In message
,
D.M. Procida writes
chris French wrote:

It'd be worth installing CAT6 cable and Gigabit switches, for a bit of
future proofing.

Gigabit ethernet runs happily over Cat 5e.

True, but if installing fixed cables in such locations, it'd be worth
considering Cat6, be setup for 10Gigbit as well :-)

Does anybody really -need- that?..

I said the same of 10M ethernet. Fixed wiring will be in place a long
time.


NT

wrote:
tony sayer wrote:
In article , chris French
scribeth thus
In message
,
D.M. Procida writes
chris French wrote:

It'd be worth installing CAT6 cable and Gigabit switches, for a bit of
future proofing.
Gigabit ethernet runs happily over Cat 5e.

True, but if installing fixed cables in such locations, it'd be worth
considering Cat6, be setup for 10Gigbit as well :-)
Does anybody really -need- that?..

I said the same of 10M ethernet. Fixed wiring will be in place a long
time.



Yup. File transfer between my machine are seriously better at 100Mbps
than 10Mbps. It is after all only 12.5MBytes/sec...think in terms of a
500 megabyte file...not huge by todays standaed if graphical.

gong to 1Gbps is 4 seconds rather than 40 seconds.

A SATA disk is around 3Gbps So even a gigabit network is three times
slower than raw file access..



NT

In article
s.com, scribeth thus
tony sayer wrote:
In article , chris French
scribeth thus
In message
,
D.M. Procida writes
chris French wrote:

It'd be worth installing CAT6 cable and Gigabit switches, for a bit of
future proofing.

Gigabit ethernet runs happily over Cat 5e.

True, but if installing fixed cables in such locations, it'd be worth
considering Cat6, be setup for 10Gigbit as well :-)

Does anybody really -need- that?..

I said the same of 10M ethernet. Fixed wiring will be in place a long
time.


NT

Yep but then again I use a 800 MHz pentium for a lot of work...
--
Tony Sayer

The message
from "TheScullster" contains these words:



Also worth considering running telephone and co-ax from central
location (if
you still use land line).
I followed suggestions on this group and took A+B pair up to a face plate
splitter in the loft and then ran land lines to each room from there.
This avoids the need for local phone filters and provides "cleaner"
broadband. Install your modem/router here also and connect to your gigabit
switch and you have wired network internet access.

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

On Mon, 26 Jan 2009 15:44:10 +0000 (GMT), "Dave Liquorice"
wrote:

On Mon, 26 Jan 2009 15:03:50 +0000, tony sayer wrote:

True, but if installing fixed cables in such locations, it'd be worth
considering Cat6, be setup for 10Gigbit as well :-)

Does anybody really -need- that?..

Maybe not now but what does the future hold?

Darkness, no lighting, intense cold, starvation, war, no telly, no
Internet, no broadband, no telephone.

Certainly nothing requiring structured wiring in a 3 bed semi unless
this 3 bed semi becomes the seat of the new government.


--

On Mon, 26 Jan 2009 21:18:07 GMT, Appin wrote:

The message
from "TheScullster" contains these words:



Also worth considering running telephone and co-ax from central
location (if
you still use land line).
I followed suggestions on this group and took A+B pair up to a face plate
splitter in the loft and then ran land lines to each room from there.
This avoids the need for local phone filters and provides "cleaner"
broadband. Install your modem/router here also and connect to your gigabit
switch and you have wired network internet access.

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

Because after a lifetime of dialling 9 for an outside line some of us
just want to pick up a phone and dial a number.

But then some of us (like me!) can't really see the point of flooding
a house with structured wiring when three or four well chosen cable
runs of cat 5 and a decent wireless router fulfill most requirements.

Fit one wired phone in a suitable place near the NTE and a one or two
handset VoIP capable cordless plugging directly into the broadband
router and it's sufficient to cover the entire house and other
locations such as a home office at the bottom of the garden, or the
garage or workshop.


--

On 25 Jan, 23:29, (D.M.
Procida) wrote:
Richard Head wrote:
I have an opportunity to get some Cat 5 cable run while we have
building/rewiring work going on.
Unless you are streaming high bandwidth video, forget cabling. Go for a
wireless router. Desktops can be retrofitted with a wireless connection for
£20 and laptops come ready fitted. Alternatively go for Ethernet over mains
adaptors.

I already have and use wireless.

Ethernet over mains can be useful where real ethernet isn't possible
(for example, if you're in a listed building). But otherwise, it's very
expensive and bears all the disadvantages of any proprietary system.

Daniele

Homeplug is an alliance not a closed system ,so prices are coming down
and speeds up:

http://www.homeplug.org

Adam

On Tue, 27 Jan 2009 00:42:09 +0000, Mike wrote:

Maybe not now but what does the future hold?

Darkness, no lighting, intense cold, starvation, war, no telly, no
Internet, no broadband, no telephone.

I can see your glass is half empty. Mines half full. B-)

Got to admit we are at the turning point between your description of the
future and one that is similar to our current one but far far more
sustainable. It's going to be painful but at least Obama seems to realise
it unlike his, in the pocket of Big Oil, predecessor.

--
Cheers
Dave.

Mike wrote:

Maybe not now but what does the future hold?

Darkness, no lighting, intense cold, starvation, war, no telly, no
Internet, no broadband, no telephone.

Neither the builder nor the archtect said anything about preparing for
the apocalypse.

Daniele

Adam Aglionby wrote:

Ethernet over mains can be useful where real ethernet isn't possible
(for example, if you're in a listed building). But otherwise, it's very
expensive and bears all the disadvantages of any proprietary system.

Homeplug is an alliance not a closed system ,so prices are coming down
and speeds up:

http://www.homeplug.org

It's still a proprietary system, rather than a standard that anyone can
manufacture to (even if the manufacturer base is widening).

Did you look at the Flash slideshow on their homepage? The US mains plug
looks scarily primitive!

Daniele

Appin wrote:

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

I can't imagine why I'd want one!

Daniele

Appin wrote:
The message
from "TheScullster" contains these words:



Also worth considering running telephone and co-ax from central
location (if
you still use land line).
I followed suggestions on this group and took A+B pair up to a face plate
splitter in the loft and then ran land lines to each room from there.
This avoids the need for local phone filters and provides "cleaner"
broadband. Install your modem/router here also and connect to your gigabit
switch and you have wired network internet access.

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

Its a curious point.

Many people don't even think of doing it. they just want 'phones like
they are used to' everywhere..or DECT.

Dave Liquorice wrote:
On Tue, 27 Jan 2009 00:42:09 +0000, Mike wrote:

Maybe not now but what does the future hold?
Darkness, no lighting, intense cold, starvation, war, no telly, no
Internet, no broadband, no telephone.

I can see your glass is half empty. Mines half full. B-)

Got to admit we are at the turning point between your description of the
future and one that is similar to our current one but far far more
sustainable. It's going to be painful but at least Obama seems to realise
it unlike his, in the pocket of Big Oil, predecessor.

The things we CAN afford WILL be internet.

Whether we are cold and dark depends largely on whether the prejudice
against nuclear power prevails or not.

same for starvation, really. Given the energy, the food can be grown.

War? yes..thats a very real possibility.

No Telly? Yup. end of commercial broadcasting for sure, and decent films.

But scads of Internet Broadband and telephone. These things are cheap.

D.M. Procida wrote:
Appin wrote:

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

I can't imagine why I'd want one!

Daniele

Well in my case is was a simple question of a large house, with two
lines and many phones..more than could be reliably driven by the BT line.

Plus three possible 'front doors' needing bells.

And a construction that is very radio opaque. DECT a nogo

A 3 into 8 PABX using the cheapest scrap phone plus three doorphones did
the job beautifully.

Plus when I have cooked supper, I can phone my somewhat deaf wife,
rather than shouting up the stairs, which irrtates her.

But the real bonus is being able to transfer the mother in law to her
without having to run up and down the stairs..

"tony sayer" wrote in message
...
In article , chris French
scribeth thus
In message
,
D.M. Procida writes
chris French wrote:

It'd be worth installing CAT6 cable and Gigabit switches, for a bit of
future proofing.

Gigabit ethernet runs happily over Cat 5e.

True, but if installing fixed cables in such locations, it'd be worth
considering Cat6, be setup for 10Gigbit as well :-)

Does anybody really -need- that?..

Of course..... actually I'd like to know about running a fibre optic cable.

whisky-dave coughed up some electrons that declared:


"tony sayer" wrote in message
...
In article , chris French
scribeth thus
In message
,
D.M. Procida writes
chris French wrote:

It'd be worth installing CAT6 cable and Gigabit switches, for a bit of
future proofing.

Gigabit ethernet runs happily over Cat 5e.

True, but if installing fixed cables in such locations, it'd be worth
considering Cat6, be setup for 10Gigbit as well :-)

Does anybody really -need- that?..

Of course..... actually I'd like to know about running a fibre optic
cable.

Lookup "Siemon" - we used their fibre terminations at Imperial College, was
quite easy to do with minimal tools and a bit of practise. Mind
you, "proving" the cable (other than plugging it in and seeing if it
worked) needed rather expensive equipment.

http://www.siemon.com/uk/e-catalog/E...ble-connectors

http://www.siemon.com/uk/e-catalog/E...ble-connectors

http://www.siemon.com/uk/e-catalog/E...lex-connectors

Cheers

Tim

On 26 Jan, 21:18, Appin wrote:

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

Once you have a decent network you can use Asterisk, no need for phone
lines at all.

whisky-dave wrote:
"tony sayer" wrote in message
...
In article , chris French
scribeth thus
In message
,
D.M. Procida writes
chris French wrote:

It'd be worth installing CAT6 cable and Gigabit switches, for a bit of
future proofing.
Gigabit ethernet runs happily over Cat 5e.

True, but if installing fixed cables in such locations, it'd be worth
considering Cat6, be setup for 10Gigbit as well :-)
Does anybody really -need- that?..

Of course..... actually I'd like to know about running a fibre optic cable.



Running the cable is easy.
Terminating it is not.

The Natural Philosopher coughed up some electrons that declared:

whisky-dave wrote:
"tony sayer" wrote in message
...
In article , chris French
scribeth thus
In message
,
D.M. Procida writes
chris French wrote:

It'd be worth installing CAT6 cable and Gigabit switches, for a bit
of future proofing.
Gigabit ethernet runs happily over Cat 5e.

True, but if installing fixed cables in such locations, it'd be worth
considering Cat6, be setup for 10Gigbit as well :-)
Does anybody really -need- that?..

Of course..... actually I'd like to know about running a fibre optic
cable.



Running the cable is easy.
Terminating it is not.


It's not actually *that* difficult these days. Systems vary - but the Siemon
crimp SC system was taught to me in about 15 minutes and the special tools
involved a) the correct crimps; b) a special little measuring and snapping
thingy. The system was "dry" as in no funny oils or epoxies.

I'm not saying it's simple, but with an instruction sheet it's within the
remit of someone with a steady hand and good eyesight.

Cheers

Tim

whisky-dave wrote:

Of course..... actually I'd like to know about running a fibre optic cable.

http://www.aaisp.net.uk/news-2009-01-ethernet.html

Pete

Appin wrote:

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

Because noone ever phones on the landline and I never phone out on it.
If I want to talk to Fred I press his name on the phone in my pocket, if
Bob wants to talk to me he presses my name on the phone in his pocket.
This is simple and works everywhere. Why would I want to use a different
and more clunky system just because I happen to be at home?

Pete

The Natural Philosopher wrote:

Crimping cat 5 structured solid core cable into plugs never really
produces reliability.

I've done it for our cheapo home LAN and had no problems - all cat5 solid
cabling goes direct to loft switch without a patch panel on the way.
Wouldn't risk it if there was to be any movement though.

Pete Verdon wrote:
Appin wrote:

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

Because noone ever phones on the landline and I never phone out on it.
If I want to talk to Fred I press his name on the phone in my pocket, if
Bob wants to talk to me he presses my name on the phone in his pocket.
This is simple and works everywhere. Why would I want to use a different
and more clunky system just because I happen to be at home?


Beacause you live in a faraday cage.

Because phones plugged into wall sockets don't get lost,stolen, or run
out of charge.

Because you need a landline for ADSL so why not use it?

Pete

On Tue, 27 Jan 2009 21:02:29 +0000, Pete Verdon wrote:

If I want to talk to Fred I press his name on the phone in my pocket, if
Bob wants to talk to me he presses my name on the phone in his pocket.
This is simple and works everywhere.

I would almost put money on it not working particulary reliably here. But
hey if you can put up with phone calls with dropouts, distortion and
having to continually repeat things or get things repeated that's up to
you.

Why would I want to use a different and more clunky system just because
I happen to be at home?

Because mobile coverage is anything but reliable or universal, the voice
quality is poor and the delay annoying.

--
Cheers
Dave.

In uk.d-i-y, The Natural Philosopher wrote:
Pete Verdon wrote:
Appin wrote:

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.
Because noone ever phones on the landline and I never phone out on
it. If I want to talk to Fred I press his name on the phone in my
pocket, if Bob wants to talk to me he presses my name on the phone in
his pocket. This is simple and works everywhere. Why would I want to
use a different and more clunky system just because I happen to be at
home?

Beacause you live in a faraday cage.

Because phones plugged into wall sockets don't get lost,stolen, or run
out of charge.

Because you need a landline for ADSL so why not use it?

Because it's useful to have a number that will reach whoever happens to
be home at the time.

--
Mike Barnes

On 27 Jan, 09:11, (D.M.
Procida) wrote:
Adam Aglionby wrote:
Ethernet over mains can be useful where real ethernet isn't possible
(for example, if you're in a listed building). But otherwise, it's very
expensive and bears all the disadvantages of any proprietary system.

Homeplug is an alliance not a closed system ,so prices are coming down
and speeds up:

http://www.homeplug.org

It's still a proprietary system, rather than a standard that anyone can
manufacture to (even if the manufacturer base is widening).

Did you look at the Flash slideshow on their homepage? The US mains plug
looks scarily primitive!

Daniele

Thats the advanced US plug, with an earth pin! ;-)

Adam

The message
from The Natural Philosopher contains these words:

Appin wrote:
The message
from "TheScullster" contains these words:



Also worth considering running telephone and co-ax from central
location (if
you still use land line).
I followed suggestions on this group and took A+B pair up to a face
plate
splitter in the loft and then ran land lines to each room from there.
This avoids the need for local phone filters and provides "cleaner"
broadband. Install your modem/router here also and connect to your
gigabit
switch and you have wired network internet access.

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

Its a curious point.

Many people don't even think of doing it. they just want 'phones like
they are used to' everywhere..or DECT.

I think that's just it. All too often people don't think logically.

The message
from The Natural Philosopher contains these words:

D.M. Procida wrote:
Appin wrote:

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

I can't imagine why I'd want one!

Daniele

Well in my case is was a simple question of a large house, with two
lines and many phones..more than could be reliably driven by the BT line.

Plus three possible 'front doors' needing bells.

And a construction that is very radio opaque. DECT a nogo

A 3 into 8 PABX using the cheapest scrap phone plus three doorphones did
the job beautifully.

Plus when I have cooked supper, I can phone my somewhat deaf wife,
rather than shouting up the stairs, which irrtates her.

But the real bonus is being able to transfer the mother in law to her
without having to run up and down the stairs..

Clearly your lifestyle has certain similarities to mine.

The message
from Pete Verdon d
contains these words:

Appin wrote:

Beats me why one should go to all the trouble to install a decent
network setup and yet fail to install even a simple PABX for the
landline/s.

Because noone ever phones on the landline and I never phone out on it.
If I want to talk to Fred I press his name on the phone in my pocket, if
Bob wants to talk to me he presses my name on the phone in his pocket.
This is simple and works everywhere. Why would I want to use a different
and more clunky system just because I happen to be at home?

Because if you were like most people, you'd find that many people phone
on landlines -- though that's not a reason for you at the moment

Because you could phone out for "nothing" i.e. at no marginal cost on
any reasonable landline deal whereas mobile deals don't generally have
unlimited calls during the day

The message
from The Natural Philosopher contains these words:



Because phones plugged into wall sockets don't get lost,stolen, or run
out of charge.

or simply experence permanent battery death remarkably quickly

The message et
from "Dave Liquorice" contains these words:


Because mobile coverage is anything but reliable or universal, the voice
quality is poor and the delay annoying.


And because handsfree is generally simpler and better with a good office phone

In article ,
Rod writes:
Is the price difference between 100M and 1G for small switches
significant? Yes - there is still a premium, but not that much.

IME, for unmanaged switches:
100Mb 5 or 8 port switches under £10 brand new.
1Gb 8 port switches were down to £30 brand new,
but have crept up a bit since the pound dropped.

Occasionally you can get a bargin from eBay second hand
(I got a Netgear GS108 8 port 1GB switch for £30; this
make would normally be much more), but more usually I see
second hand ethernet switches going for more much more on
eBay than they cost brand new (if you search around).

Agreed about 5e working fine at gigabit - but I would always use 6/6a in
a harsh environment (e.g. a server cabinet) or for longer distances.

I wouldn't bother with cat 6 for home use. My home network
is 1Gb, which is pretty well matched to the data rate I can
get from a pair of 7200RPM mirrored SATA drives. (Drives
are about 75Mbyte/sec sustained, and mirroring gets me to
something over 100Mbytes/sec sustained read rate, which is
similar speed to 1Gbit network. To make good use of 10Gb,
you'd need a filesystem striped across many disks, even
when using Enterprise class 15k RPM disks, or to wait for
solid state disks to replace spinning rust.)

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Andrew Gabriel wrote:
In article ,
Rod writes:
Is the price difference between 100M and 1G for small switches
significant? Yes - there is still a premium, but not that much.

IME, for unmanaged switches:
100Mb 5 or 8 port switches under £10 brand new.
1Gb 8 port switches were down to £30 brand new,
but have crept up a bit since the pound dropped.

Occasionally you can get a bargin from eBay second hand
(I got a Netgear GS108 8 port 1GB switch for £30; this
make would normally be much more), but more usually I see
second hand ethernet switches going for more much more on
eBay than they cost brand new (if you search around).

Agreed about 5e working fine at gigabit - but I would always use 6/6a in
a harsh environment (e.g. a server cabinet) or for longer distances.

I wouldn't bother with cat 6 for home use. My home network
is 1Gb, which is pretty well matched to the data rate I can
get from a pair of 7200RPM mirrored SATA drives. (Drives
are about 75Mbyte/sec sustained, and mirroring gets me to
something over 100Mbytes/sec sustained read rate, which is
similar speed to 1Gbit network. To make good use of 10Gb,
you'd need a filesystem striped across many disks, even
when using Enterprise class 15k RPM disks, or to wait for
solid state disks to replace spinning rust.)


I actually meant to include a comment there about 100M being somewhat
short sighted given that many (most?) machines now come with gigabit as
standard. The price differences you quoted (and which I have now checked
on my usual sources) are greater than I thought - looks like the 10/100
stuff has slipped down in price and the gigabit gone up a bit.

I doubt many of us have the level of harsh environment I mentioned in
our houses - so, yes, unlikely to use Cat 6 at home.

--
Rod

Hypothyroidism is a seriously debilitating condition with an insidious
onset.
Although common it frequently goes undiagnosed.
www.thyromind.info www.thyroiduk.org www.altsupportthyroid.org

Andrew Gabriel wrote:

I wouldn't bother with cat 6 for home use. My home network
is 1Gb, which is pretty well matched to the data rate I can
get from a pair of 7200RPM mirrored SATA drives. (Drives
are about 75Mbyte/sec sustained, and mirroring gets me to
something over 100Mbytes/sec sustained read rate, which is
similar speed to 1Gbit network. To make good use of 10Gb,
you'd need a filesystem striped across many disks, even
when using Enterprise class 15k RPM disks, or to wait for
solid state disks to replace spinning rust.)


Moore's Law (doubling every 18 months) does apply to disk transfer
rates. So Gigabit is fine now, and will be for 18 months (one doubling)
and from then on will be a problem for certain uses. It's the *cable*
I'd suggest forking out for, not the electronics - the cable is there
for the long term.

In article ,
Andy Champ writes:
Andrew Gabriel wrote:

I wouldn't bother with cat 6 for home use. My home network
is 1Gb, which is pretty well matched to the data rate I can
get from a pair of 7200RPM mirrored SATA drives. (Drives
are about 75Mbyte/sec sustained, and mirroring gets me to
something over 100Mbytes/sec sustained read rate, which is
similar speed to 1Gbit network. To make good use of 10Gb,
you'd need a filesystem striped across many disks, even
when using Enterprise class 15k RPM disks, or to wait for
solid state disks to replace spinning rust.)


Moore's Law (doubling every 18 months) does apply to disk transfer
rates.

Unfortunately not. Disk capacities don't lag too far 18 month doubling
now, but all other disk performance parameters lag way behind this,
which is why disk performance has steadily become a more and more
limiting factor in performance of many computing applications.
A quick calculation shows disk transfer rates have doubled about
every 45 months over the last 25 years. That's one reason
applications often require complex disk array infrastructures, to
make up for the serious [relative] lag of disk performance behind
the progress made in CPU performance.

Out of interest, here's a table of relative performance changes
I use in a presentation I give on filesystem performance from time
to time...

25 years ago Today Improvement

Rotational speed 3,600 15,000 4x
I/O's per sec 30 300 10x
Transfer rates 1 MB/s 100 MB/s 100x
Capacity 150 MB 1.5 TB 10,000x

CPU performance 4 MIPS 400,000 MIPS 100,000x

The CPU performance improvement is pretty much spot on for doubling
every 18 months. All the disk performance parameters lag behind,
mostly _way_ behind. The exponential increase in disk capacity is
not linear over the period, being faster in more recent years, which
is why it's nearly on doubling every 18 months now. When SSD's become
mainstream, there will be a giant discontinuity in disk performance.
They're still too expensive and too small to use other than in some
specialist situations, but that's changing fast.

(Note that Moore's Law is really a doubling of transistor counts on
a chip every 2 years, although it's often used to refer to any
exponential gain scheme.)

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Andrew Gabriel wrote:

Unfortunately not. Disk capacities don't lag too far 18 month doubling
now, but all other disk performance parameters lag way behind this,
which is why disk performance has steadily become a more and more
limiting factor in performance of many computing applications.
A quick calculation shows disk transfer rates have doubled about
every 45 months over the last 25 years. That's one reason
applications often require complex disk array infrastructures, to
make up for the serious [relative] lag of disk performance behind
the progress made in CPU performance.

Out of interest, here's a table of relative performance changes
I use in a presentation I give on filesystem performance from time
to time...

25 years ago Today Improvement

Rotational speed 3,600 15,000 4x
I/O's per sec 30 300 10x
Transfer rates 1 MB/s 100 MB/s 100x
Capacity 150 MB 1.5 TB 10,000x

CPU performance 4 MIPS 400,000 MIPS 100,000x

The CPU performance improvement is pretty much spot on for doubling
every 18 months. All the disk performance parameters lag behind,
mostly _way_ behind. The exponential increase in disk capacity is
not linear over the period, being faster in more recent years, which
is why it's nearly on doubling every 18 months now. When SSD's become
mainstream, there will be a giant discontinuity in disk performance.
They're still too expensive and too small to use other than in some
specialist situations, but that's changing fast.

(Note that Moore's Law is really a doubling of transistor counts on
a chip every 2 years, although it's often used to refer to any
exponential gain scheme.)


Maybe the new faster flash memory devices will be able to provide the
performance jumps required to feed 10Gb? :-)

--
Rod

Hypothyroidism is a seriously debilitating condition with an insidious
onset.
Although common it frequently goes undiagnosed.
www.thyromind.info www.thyroiduk.org www.altsupportthyroid.org

Rod wrote:
Andrew Gabriel wrote:
lots of interesting stuff of which I leave just one line

Transfer rates 1 MB/s 100 MB/s 100x

I stand corrected. That suggests gigabit will last much longer than I
thought.

Maybe the new faster flash memory devices will be able to provide the
performance jumps required to feed 10Gb? :-)

Unlikely. The big gain with SSDs (flash or not) isn't the transfer
rate, it's the latency. Or to translate that:

The peak rate isn't much different. You get similar rates - which isn't
too surprising, as they are usually hung off the same bus that was
designed to handle disc traffic.

But when you ask for a sector, you get it immediately. There's none of
this move the head to the right place, wait for the disc to spin to the
right place, read some data you get with discs. It just so happens I
ran a benchmark on a USB thumb drive the other day. While transfer rate
is nothing special, latency (which is typically several mS for a disc)
came out as 900 microseconds.

Andy

Andy Champ wrote:
Rod wrote:
Andrew Gabriel wrote:
lots of interesting stuff of which I leave just one line

Transfer rates 1 MB/s 100 MB/s 100x

I stand corrected. That suggests gigabit will last much longer than I
thought.

Maybe the new faster flash memory devices will be able to provide the
performance jumps required to feed 10Gb? :-)

Unlikely. The big gain with SSDs (flash or not) isn't the transfer
rate, it's the latency. Or to translate that:

The peak rate isn't much different. You get similar rates - which isn't
too surprising, as they are usually hung off the same bus that was
designed to handle disc traffic.

But when you ask for a sector, you get it immediately. There's none of
this move the head to the right place, wait for the disc to spin to the
right place, read some data you get with discs. It just so happens I
ran a benchmark on a USB thumb drive the other day. While transfer rate
is nothing special, latency (which is typically several mS for a disc)
came out as 900 microseconds.

Andy

SSD speeds have improved quite a lot - 220 MB/s now available (or at
least announced) from Samsung. And I would guess they likely have
further improvements not far behind.

--
Rod

Hypothyroidism is a seriously debilitating condition with an insidious
onset.
Although common it frequently goes undiagnosed.
www.thyromind.info www.thyroiduk.org www.altsupportthyroid.org

In article ,
Andy Champ writes:
Rod wrote:
Andrew Gabriel wrote:
lots of interesting stuff of which I leave just one line

Added back a second one for comment further down...


I/O's per sec 30 300 10x
Transfer rates 1 MB/s 100 MB/s 100x

I stand corrected. That suggests gigabit will last much longer than I
thought.

Maybe the new faster flash memory devices will be able to provide the
performance jumps required to feed 10Gb? :-)

Unlikely. The big gain with SSDs (flash or not) isn't the transfer
rate, it's the latency. Or to translate that:

Yes, indeed. That translates into the number of I/O's per second (IOPS).
There are now read-biased Enterprise SSD's giving 50,000 IOPS (reads),
verses 300 IOPS you get from todays Enterprise disks (SAS or fibre channel).
This can give you an astonishing speedup of applications which use
synchronous disk i/o, as they are predominately limited by the number
of IOPS they can get through the disk subsystem. 80,000 IOPS is probably
about the limit of what you can get across current disk interconnects
in any case, and actually way exceeds what most of todays disk controllers
can handle, given they weren't designed for disks that fast.

The peak rate isn't much different. You get similar rates - which isn't
too surprising, as they are usually hung off the same bus that was
designed to handle disc traffic.

But when you ask for a sector, you get it immediately. There's none of
this move the head to the right place, wait for the disc to spin to the
right place, read some data you get with discs. It just so happens I
ran a benchmark on a USB thumb drive the other day. While transfer rate
is nothing special, latency (which is typically several mS for a disc)
came out as 900 microseconds.

Yes. An Enterprise SSD should get something even better, although I don't
have a figure to hand.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Rod coughed up some electrons that declared:


Maybe the new faster flash memory devices will be able to provide the
performance jumps required to feed 10Gb? :-)


Generally, flash has fairly slow transfers in bytes/sec - just about
matching disks for the best and most expensive flash.

However, flash does have the advantage of very short random seek times.

Cheers

Tim