DComTalk.com

James Knott wrote:

Vernon Schryver wrote:

The good reason your box might support RIP is to advertise a default
route to hosts on your home network.

How many hosts respond to RIP? If there's only one route to the internet,
there's no need for RIP.

no need for a routing table either if only one entry(though at least it
uses it). It dosen't even seem to use the routing protocol. But I
guess the reason it has these is that the technology is already around
and is no big deal to implement, since home routers already have their
own OS and web server built in. So, why not a routing table, and why
not a routing protocol like RIP that is just not being used. If the
router is built using things that already exist, then there's no point
removing the RIP or routing table from it.

Apparently even ethernet repeaters were built with old NICs , so I
guess the MAC address was ignored. Same principle. If the technology
is already there and not expensive, it's cheaper to use it as it is
use it as it is, and if there are unnecessary features, just let them
be and don't use them.

In comp.dcom.lans.ethernet Rod Dorman <rodd@panix.com> wrote:

I thought a "switch" was that thing on the wall you toggle to make the
lights turn on and off :-)

Nah, what your are thinking of is a layer one repeater with
user-enabled firewall functionality :)

rick jones
--
Process shall set you free from the need for rational thought.
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

Rick Jones <rick.jones2@hp.com> wrote:

The smallest unit a CPU fetches from memory is a cacheline.
These days, 64 byte cachelines are common, as are 128 byte
cache lines. Some CPUs have automagic "buddy prefetch"
that makes a 64 byte cache line size behave more like 128.
Etc etc etc...

Yes, but are GP CPUs used for routers? I doubt it. They'll
need a complete redesign. BTW: has IPv6 gone Little-Endian?

-- Robert

James Knott <james.knott@rogers.com> wrote:

One other thing they're trying to do, is arrange addresses
geographically, so you'd have, for example, a route to
Europe and only once there, worry about what country etc.
This should cut down considerably on routing tables.

Yes, it should, but only if there's enough direct connections.
For many years, much of intraeuropean traffic (eg *.fr to *.de)
was routed through MAE East or euro ISP direct links to the US.
I was surprised that Brussels hadn't set up MAE Europe.

-- Robert

J. Clarke <jclarke.usenet@snet.net.invalid> wrote:

Just look at the FCC failure on HDTV.

What "failure"? If you mean that everybody hasn't rushed out
and gotten an HD receiver, why should they if they don't want HD?

Failure because the US FCC desparately wants to pull the plug on
VHF & UHF NTSC broadcast and auction off these great swathes of
spectrum. They can't because far too many people are staying on it.

In constrast DVD has overtaken VHS not because of
convenience and production cost, but due to a surprising
quality improvement. Who dreamed NTSC could look so good?

Well, actually it's convenience and production cost.

No, it is not. Had these been sufficient drivers,
videodisk and later VCD would have taken over.

DVD looks pretty crappy next to ATSC by the way.

So? People still buy lots of these portable DVD
players with 250 line screens! And listen to MP3s.
The amount of money people are willing to pay for
quality upgrades is definitely limited.

-- Robert

James Knott <james.knott@rogers.com> wrote:

There are a couple of things driving IPv6. The most obvious
is limited addresses in IPv4. According to what I read a
while ago, the number of IPv4 addresses assigned to China,
would be insufficient for a large ISP in North America!

That maybe so, but from the way the Chinese are approaching
the internet (Great fireWall of China), they like it that way.
One IP for the whole 1.2 billion of 'em :) I think they just
might run out of ports.

IPv6 also supports encryption and authentication, by
default. The extention headers make it easier to support
new protocols etc.

Easier. I still don't hear "kill app".

-- Robert

J. Clarke <jclarke.usenet@snet.net.invalid> wrote:

Actually it is not uncommon for GP CPUs to be used for
routers--some Cisco models have Intel processors and PCI
Buses and are basically PCs with a different OS.

I'm appalled. Those will be able to handle a few 100 Mbit/s,
not more. The PCI bus cannot handle gigabit (too much overhead).

Serious routers need backplanes & switching ASICs.

Other routers are just Linux running on an embedded chip
of some sort.

Yes, my home router is an ARM4000.

-- Robert

J. Clarke <jclarke.usenet@snet.net.invalid> wrote:

The only "great swathes of spectrum" that will become
available when analog broadcast is discontinued will be
the UHF channels above 51.

IIRC, the FCC originally wanted all VHF & UHF broadcast
shutdown by 2006?

Could you burn a videodisk in your PC? How many titles
were available on VCD?

Respectively: few people burn DVDs; Chicken & egg.

So let's see, on the one hand DVD succeeded because of high
image quality but on the other nobody cares about image
quality? Would you be kind enough to make up your mind?

Easy. It ain't binary. The combination of user convenience
(users don't care VHS is harder to print) _and_ quality was enough
to clear the hurdle. Neither alone was enough. With the law of
diminishing return, it will take a huge increase in quality to
get the same market push.

Look at the durability of music CD format. There is better
available, but it is unlikely to succeed. Worse quality (MP3s)
might.

-- Robert

James Knott wrote:

Vernon Schryver wrote:

The good reason your box might support RIP is to advertise a default
route to hosts on your home network.

How many hosts respond to RIP? If there's only one route to the internet,
there's no need for RIP.

strange that it uses RIP then. Maybe just the technology was there in
router operating system software. The HW just doesn't make full use of
it.

I suppose since a routign protocol isn't used. They could have built a
device that wasn't a router/didn't do routing. But still got it to the
ISP. Just not iwth a routing protocol or routing table

(I know somebody said that a router is any layer 3 device, and it need
not be running a routing protocol. But I have never even heard of any
make/model of any such device.)

Robert Redelmeier wrote:

And listen to MP3s.
The amount of money people are willing to pay for
quality upgrades is definitely limited.

You can't expect anyone who listens to Britney Spears, to know anything
about quality. ;-)

Robert Redelmeier wrote:

Rick Jones <rick.jones2@hp.com> wrote:
The smallest unit a CPU fetches from memory is a cacheline.
These days, 64 byte cachelines are common, as are 128 byte
cache lines. Some CPUs have automagic "buddy prefetch"
that makes a 64 byte cache line size behave more like 128.
Etc etc etc...

Yes, but are GP CPUs used for routers? I doubt it. They'll
need a complete redesign.

Actually it is not uncommon for GP CPUs to be used for routers--some Cisco
models have Intel processors and PCI Buses and are basically PCs with a
different OS.

Other routers are just Linux running on an embedded chip of some sort.

No real magic here.

BTW: has IPv6 gone Little-Endian?

-- Robert

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

Robert Redelmeier wrote:

J. Clarke <jclarke.usenet@snet.net.invalid> wrote:
Just look at the FCC failure on HDTV.

What "failure"? If you mean that everybody hasn't rushed out
and gotten an HD receiver, why should they if they don't want HD?

Failure because the US FCC desparately wants to pull the plug on
VHF & UHF NTSC broadcast and auction off these great swathes of
spectrum. They can't because far too many people are staying on it.

The only "great swathes of spectrum" that will become available when analog
broadcast is discontinued will be the UHF channels above 51.

In constrast DVD has overtaken VHS not because of
convenience and production cost, but due to a surprising
quality improvement. Who dreamed NTSC could look so good?

Well, actually it's convenience and production cost.

No, it is not. Had these been sufficient drivers,
videodisk and later VCD would have taken over.

Could you burn a videodisk in your PC? How many titles were available on
VCD?

DVD looks pretty crappy next to ATSC by the way.

So? People still buy lots of these portable DVD
players with 250 line screens! And listen to MP3s.
The amount of money people are willing to pay for
quality upgrades is definitely limited.

So let's see, on the one hand DVD succeeded because of high image quality
but on the other nobody cares about image quality? Would you be kind
enough to make up your mind?

-- Robert

--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

James Knott <james.knott@rogers.com> wrote:

You can't expect anyone who listens to Britney Spears,
to know anything about quality. ;-)

Oh, fully agreed! However, the irrefutible data is that
many people listen to Ms. Spears, so presumably an equivalent
number care little for quality.

This is very unfortunate because economies of scale drive markets.

-- Robert

Robert Redelmeier <redelm@ev1.net.invalid> wrote:

J. Clarke <jclarke.usenet@snet.net.invalid> wrote:
Actually it is not uncommon for GP CPUs to be used for
routers--some Cisco models have Intel processors and PCI
Buses and are basically PCs with a different OS.

I'm appalled. Those will be able to handle a few 100 Mbit/s,
not more. The PCI bus cannot handle gigabit (too much overhead).

Um, _which_ PCI bus? There are roughly 6 of them IIRC, ranging from
33x32, to 66x32, 33x64, 66x64, 133x64 and 266x26 (the latter being
PCI-X). And then there is PCIe...

Serious routers need backplanes & switching ASICs.

That may be - the definition of "serious" may be somewhat subjective.
A home "router" may be just as "serious" to its end-user as a core
Internet router is to a NOC.

rick jones
--
a wide gulf separates "what if" from "if only"
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

Robert Redelmeier <redelm@ev1.net.invalid> wrote:

No, it is not. Had these been sufficient drivers, videodisk and
later VCD would have taken over.

Was videodisk actually "convenient?" IIRC it was rather common for a
title to span multiple discs, and they were rather large.

rick jones
--
oxymoron n, commuter in a gas-guzzling luxury SUV with an American flag
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...