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Flux gate question

J

John S

Jan 1, 1970
0
I had tried every useful tool there and got nothing. Including
anything on the domain registration.

Did my link help any?
 
J

Jasen Betts

Jan 1, 1970
0
All true, but in the end it seems not to be worth it. If you want a
dedicated LAN just for VoIP why do it in the first place? It means tons
of new cable runs, jackhammers, dirt, dust.

it shouldn't need new cable runs, there should have been excess
capacity when the cable was installed.

The voip phones I've seen all had internal 10/100 switches, if you want
to go faster you can't use the passthru socket you need a separate run
to the switch.

If you have several phones in a room you can daisy-chain them and use
wall-warts for power or put them on a local POE switch.
 
J

Joerg

Jan 1, 1970
0
Jasen said:
it shouldn't need new cable runs, there should have been excess
capacity when the cable was installed.

You mean they should have run two CAT-5 instead of one, just for the fun
of it? No way, not in business. Ok, in my case I did but to run POTS
over the other CAT-5. No way I'll let VoIP in here.

The voip phones I've seen all had internal 10/100 switches, if you want
to go faster you can't use the passthru socket you need a separate run
to the switch.

If you have several phones in a room you can daisy-chain them and use
wall-warts for power or put them on a local POE switch.

My POTS phones can just be ... plugged into an RJ-11 and that's it :)

No wall warts, no PoE. Best thing is, they always work and there are
never interruptions.
 
J

Joerg

Jan 1, 1970
0
Jeff said:
Most server based VoIP systems (i.e. Asterisk) include SNMP
monitoring. Alarms and traps are generated whenever something goes
awry, out of limits, or hiccups. During the 1990's, I used to do
quite a bit of SNMP "instrumentation" for server farms. MRTG,
RRDTool, Nagios, HP Broken View, and others were the front ends.

Sounds like monitoring nirvana? Nope... it was more like monitoring
hell. No matter how I tried, I could never get the NOC to respond to
alarms and traps. Nobody wanted to jump when a message popped up on
the console, or wanted to slog through reams of Syslog reports looking
for the culprit.

What did work was pretty pictures and graphs. Network traffic was
plotted using various tools. The admins could look at the graphs and
instantly tell if something had changed. Zero traffic is a good clue
that the line is down. Maxed out bandwidth is a good clue that the
system is under attack, or that some router was misconfigured into
dumping all its traffic via that line. Lots of other possibilities,
but the point is that a graph will show the past history, when things
changed, and what are the gross effects.

That's how it should be. No reams of faceless data but at first just one
li'l "Check System" lamp. When that's lit, a few graphs. When those
still aren't enough, some more underlying data.

The only people that do alarms and alerts are the burglar alarm
companies.

No, also aerospace people do because it saves lives there. Others should
learn from them.

There are IT service companies that specialize in maintaining Asterisk
VoIP servers. However, you're correct that these companies don't want
to deal with customer network related issues. I don't have an answer
for that problem, except to find an IT service company that can do
both.

Well, if they don't want to deal with customer network issues they
should either

a. write honest proposals that spell out that a whole new second network
is required

or

b. get out of that business.

For the last 30 years, my company motto has been:
"If this stuff worked, you wouldn't need me".
Nobody has ever disagreed.

:)


VoIP should work out of the box, but rarely does. In my never humble
opinion, VoIP configuration is the most complicated, obtuse,
confusing, difficult, and buggy part of network computing. ...


Then maybe that whole concept is no good for anything other than the
infrastructire of large teclos (where it does make sense IMHO).

... I have
dealt with network sniffing, analysis, diagnostics, and performance
issues that are comparatively trivial compared to the mess surrounding
VoIP. Unless some industry group starts over from scratch (as they
did going from ITU H.323 to SIP), it will only become more complicated
and more difficult.
<http://www.packetizer.com/ipmc/h323_vs_sip/>

Meantime we just keep switching over to cell phones if the conference
audio link goes on the fritz, like it usually does with VoIP.
 
S

Spehro Pefhany

Jan 1, 1970
0
My POTS phones can just be ... plugged into an RJ-11 and that's it :)

Generally the jacks need to be run back to a PBX or something of that
ilk, unless you only have one or two lines. That's the same work as
running another set of CAT5.
No wall warts, no PoE. Best thing is, they always work and there are
never interruptions.

PoE is better than regular phones because they generally need a wall
wart each.

Unless you're still using those black rotary dial phones.
 
J

Joerg

Jan 1, 1970
0
Spehro said:
Generally the jacks need to be run back to a PBX or something of that
ilk, unless you only have one or two lines. That's the same work as
running another set of CAT5.

Not really. Unless the business building didn't have any upgrades in the
last 100 years or so the phone lines will already be there. Same in
homes. For example here I found to my surprise that five twitsted pairs
went to just about any phone jack.

Then, you can run four phones over just one CAT-5. I my case several
links are RF so no wires at all.

PoE is better than regular phones because they generally need a wall
wart each.

None of my corded phones needs a wall wart. Why should they?

Unless you're still using those black rotary dial phones.

Nope, Panasonic Easa-Phone. Those are for PBX systems up to 28 phones.
We do have one of these in the kitchen though, except ours is a bit older:

http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=181075975097
 
J

Jasen Betts

Jan 1, 1970
0
You mean they should have run two CAT-5 instead of one, just for the fun
of it?

Yeah! it's a lot more fun to run cat _before_ the drywall goes on.
No way, not in business. Ok, in my case I did but to run POTS
over the other CAT-5. No way I'll let VoIP in here.

VOIP doesn't have to be unreliable.
 
J

Jasen Betts

Jan 1, 1970
0
Then, you can run four phones over just one CAT-5. I my case several
links are RF so no wires at all.

You can run enough data to run 30 voip phones over two cat5 pairs.
 
J

Joerg

Jan 1, 1970
0
Jasen said:
You can run enough data to run 30 voip phones over two cat5 pairs.

But you cannot tap into that string willy-nilly fashion along its
course, and that's one of the problem, requiring some new
infrastructure. With POTS you can tap in anywhere.
 
J

Joerg

Jan 1, 1970
0
Jasen said:
Yeah! it's a lot more fun to run cat _before_ the drywall goes on.

The guys who built the place here were very modern for 1970 but not
quite this modern. Plus they could not even buy CAT-5 back then.

VOIP doesn't have to be unreliable.

True, as evidenced by telcos in their infracstructure which uses VoIP,
often without their customers knowing it. But in deployments at customer
premises my impression is that even "professional" VoIP systems are to a
large extent plain unreliable when it comes to drop-outs and such.
 
J

Joerg

Jan 1, 1970
0
Jeff said:
Close. The graphs get generated continuously, whether you need them
or not. The past history is what's important. One should be able to
look at the graphs, and instantly tell that something has changed. No
waiting for the alarm in order to start graphing. That's the way all
the network monitoring software works, including the VoIP stuff. As
for the "Check System" light, don't bother. It will be lit
continuously as errors and glitches are chronic.

The "Check System" light needs to be a little smarter than that. Like in
cars where it won't light if there is the occasional misfire in the
engine. But it will be lit if this happens a lot or if there are several
misfires in a row. IOW the light does take history into account.

Aerospace responds to alarms and alerts because failures tend to be
catastrophic. Even so, such alarms and alerts are of marginal value.


They are most definitely not of marginal value. They can save lives.
Think about the stall warning or an engine imbalance warning. These
warning lights can mean the difference between a safe emergency landing
and a sad story in the evening news.

For example, there were some warnings prior the space shuttle
Challenger falling apart on re-entry, but nobody could interpret their
meaning. Same with various airline accidents, where something went
wrong, the alarm goes off, but nobody knows what it means, much less
what to do. ...


A properly trained pilot knows what each alarm means, plus there is the
handbook. There are sometimes situations, like on the Challenger, where
there isn't all that much you can do to avoid a disaster. But very often
there is.

... My favorite was a private plane that did a wheels up
landing while the tower was yelling over the radio at the pilot to
abort the landing. When asked why he didn't respond to the tower's
warning, he indicated that he couldn't hear the radio over the alarm
buzzer. Plenty of other dumb stories of alarms that were ignored.

So he landed with the alarm buzzer and didn't even bother to check the
landing gear locking lights? That would be the perfect example of
serious human error. No alert light can avoid that.

Rewind please. It was you that suggested that they were hundreds of
miles away and too busy to deal with such trivial customer complaints.


No, I said the clients are hundreds of miles away so I can't do anything
about it. What we do to fix it is that they switch from VoIP to their
cell phones.

Since I'm effectively doing much the same thing for my customers, I
have a little experience in how it works. It is impossible to respond
to every complaint, especially automated alarms and automated trouble
ticket spam generators. Even worse are customers that don't want to
bother their service providers with issues that they really don't
understand and usually can't explain in detail. I had one piece of
software that I helped produce, that shipped about 2000 copies before
anyone bothered to mention that it didn't run.

Anyway, what works best is to have a single point of contact with the
customer, so that the service company is not getting conflicting
guesses. Remote admin and logging is mandatory. Outsourcing the
switching, intercom, voice mail, etc to offsite saves considerable
effort (at the expense of additional internet bandwidth). Redundancy
and fail-over solves many reliability problems but increases costs.

Agreed, and they all have service contracts et cetera in place. But the
reality is that these VoIP systems too often do not live up to the same
quality standards as older PBX systems.

The most difficult part is finding someone who can decode the
complaint, make an intelligent assessment as to its severity, and
dispatch someone with the appropriate tools to actually fix the
problem. In my limited experience with VoIP, that's incredibly
difficult bordering on impossible. It's not that they don't want to
deal with the customers issues, they simply don't know what needs
fixing.

Then maybe they should go back to PBX because that's not as complicated
and can be handled by a local telco service technician :)

Yeah, that works. I think I've spent more time dealing with the
issues of having a hot standby system, VLAN's, fail-over, etc than
with single stand alone systems. Redundancy is not easy.
Incidentally, only the largest systems have separate CAT5 for the VoIP
system. Most use the same wiring as the computers, but use a VLAN to
separate the traffic.

The ones I have personally seen were of the 2nd category. But the
traffic separation either isn't all that successful or there's other
issues. Fact is, calls nearly always go through but then chunks of the
conversation (mostly from their side) vanish. Sometimes to the point
where whole sentences become unintelligible. The VoIP party often won't
know unless a caller tells them. Then it's usually "Oh, dang, again?".

It was similar with cell networks in the 90's. There were times when I
had to ask a caller to please stop at the next phone booth and call on a
landline. Now they are better, but not all of them.

Believe me, I really don't want to do VoIP. It's way too much work
and involves far too many unrealistic expectations for the customer.
However, literally all of my business office customers want and use
VoIP. All I insist is that they have one POTS line handy not for
failures, but so I can take the system down without killing all the
incoming phone services (and talk to the VoIP service provider tech
support while trying to fix their latest screwups).

On one system we went as far as having a dedicated cell link from the
rooftop.

Nope. The concept is good, but the implementation is lacking. Lots
of reasons. I can detail if anyone is interested.

I don't doubt that. After all, the telcos successfully use VoIP. But
it's dedicated lines, usually. I only see this from a business
perspective and from that view point a system is only good if there is
enough success in general implementations. With VoIP that just isn't the
case.

It's nice to have a fallback, but as I previously suggested, there may
be something wrong with the way this particular VoIP system works.


And nearly all others :-(

Except for my own office (long story here), all of my VoIP systems
work well thanks to QoS and adequate reserved bandwidth for the number
of instruments.

That is great. But unfortunately there are a lot of other VoIP networks
out there that I'd consider unreliable. It is very similar with web
conferencing services. There are some that work flawlessly every single
time. Then there are some (big ones) that notoriously fails and have
poorly designed support software.
 
All true, but in the end it seems not to be worth it. If you want a
dedicated LAN just for VoIP why do it in the first place? It means tons
of new cable runs, jackhammers, dirt, dust.

THe VOIP phones here at work are on the same cable as our laptops. The
PC plugs into the phone. It works fine. What doesn't isn't the fault
of VOIP or the network hardware.
 
But you cannot tap into that string willy-nilly fashion along its
course, and that's one of the problem, requiring some new
infrastructure. With POTS you can tap in anywhere.

Even POTS in homes is run in a star now. It's easier.
 
J

Joerg

Jan 1, 1970
0
Even POTS in homes is run in a star now. It's easier.


Well, our home is from 1970, so ...

But the new runs I did are all home-run style to a central wire closet,
of course.
 
J

Joerg

Jan 1, 1970
0
Jim said:
That seems to be the convention around here... all new construction
has a central wiring closet for POTS, CATV and CAT5+

Soon I'll have to do another coax plus CAT-5 run. Closet, umpteen feet
of crawl space, up to where the lab bench is. Not looking forward to
that job, one never knows who else lives down there.

http://hvac-talk.com/vbb/showthread.php?77429-Snakes/page2&s=fbe9efeb81f24d734837558235383933

Quote "About the rattle snakes in crawl spaces,i lay there real still
untile they slitther away then i get the hell out. The boa was a
different story & didn`t wait around to say hi". ... Yikes, that
wouldn't be a job for me.
 
Well, our home is from 1970, so ...

THAT'S OLD! ;-)
But the new runs I did are all home-run style to a central wire closet,
of course.

Well, my houses (one is for sale) were both built in 2007. Both have
cute wiring. Both are wired in a star but one is missing some copper
in the middle of some of the runs and this one is missing the end of
the wires that come together. It seems inspectors miss little details
like that. :-( I'm rewiring it as need be. Other than the two
bedrooms upstairs, it's not too hard (unfinished basement). I'll have
to rip up some sheetrock to get the upstairs (one room won't be too
hard).
 
J

Joerg

Jan 1, 1970
0
THAT'S OLD! ;-)

Nah. As a kid I participated in training at a public swimming pool that
was built by the Romans and still in service. No kidding. Of course they
had installed chlorination equipment and such per latest health
standards. But some of the tile work was really ancient and so was the
structure of the building.

Well, my houses (one is for sale) were both built in 2007. Both have
cute wiring. Both are wired in a star but one is missing some copper
in the middle of some of the runs and this one is missing the end of
the wires that come together. It seems inspectors miss little details
like that. :-( I'm rewiring it as need be. Other than the two
bedrooms upstairs, it's not too hard (unfinished basement). I'll have
to rip up some sheetrock to get the upstairs (one room won't be too
hard).


New houses have advantages when it comes to infrastructure but typically
not when it comes to build quality. This one has massive beams
everywhere. Raised foundation, lots of 2*12 underneath, piered ever few
feet, 2" concrete pour on the floors, nothing moves at all if you jump
up and down in the center of the room here. Try that in a new house.
Same on the roof, you could do a Sirtaki dance up there with a large
group and none fo the rafters would wobble. Because even those are
overkill by today's "standard".
 
J

Jasen Betts

Jan 1, 1970
0
But you cannot tap into that string willy-nilly fashion along its
course,

sure you can all the IP phone's I've seen have internal switches.
 
J

Joerg

Jan 1, 1970
0
Jeff said:
Run conduit for the signal wires. That way you can add and delete as
required.

I like "Smurf Tube", also known as Carlon Resi-Gard:
<http://www.carlonsales.com/techinfo/installationtraining/IT-7F72.pdf>
<http://www.carlonsales.com/flexplusblueent.php>

Another vendor of similar conduit:
<http://store.cablesplususa.com/networking-infrastructure-premier-conduit-raceway.html>

Type NM electrical conduit will also work, but is more expensive.

I wish I could but it becomes nearly impossible as a afterthought
because I'd have to rip out drywall and, worse, tile work and stuff in
order to get through walls. With tiles that results in major remodel
because there are no spares and the chances of obtaining such tile after
more than 40 years are zilch.

Snaking a CAT-5 around things is a little easier. Quad-shield coax,
different story, but through conduit with narrow turns that isn't easy
either.

Don't forget to leave a pull string in the conduit.

I have 1" conduit running between floors and to the roof in my house,
but not along the walls. Not optimum, but better than a giant tangle
of cables running up the walls.

I don't run anything along the roof on in the partial attic. It'll bake
out over summer and eventually become brittle.

One of my customers is currently ripping out coax, long CAT5e runs,
and 25 pair telco cable. They're being replaced by CAT6 and fiber. If
they had installed conduit, it would have been MUCH easier. Conduit is
also a good idea if you're thinking of home theater.

Our home theater performances are provided by two Labradors :)

But seriously, TV or movies rank very low on our food chain.
 
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