Isn't/Wasn't there a shorage of phone lines?

[mm]

To alt.home.repair:

Did dial-up ever cause a shortage of phone lines? I never heard that, but I am surprised if the phone companies had the capacity to fulfill maybe a 50 to 300% increase in demand over the course of 10 years, from soon after dial-up's startup to its peak. There are people who spent maybe a half hour a day on the phone before the net, who must have spent 12 hours a day on the phone/modem after the net. Combined with all those who only used it for an hour extra, that's an enormous increase.

When I first got dialup, there weren't that many ways to use the Net, I didn't have that as many ways as one might have. So I was only on an hour or two a day. And even when I got more uses, I tried to stay on no more than maybe 3 hours to not tie up the phone lines. But I'm sure most people are not that considerate.

A lot of people have gone to cable now, but there was a period were

20, 40, 80? million people had dial-up and they stayed on for hours and hours, maybe all day. (Now that I know usage has slacked off, and I've never heard of shortages, I've stayed on for 36 hours once, for some reason I forget. And other days 12 hours.)

Cnversely, is there now a lot of excess capacity on phone-only lines, now that many people have switched to cable? Doesn't even switching to DSL end up using new central station hardware, leaving old phone-only hardware unused?

[Don Phillipson]

This seems unlikely because intercity calls began approx.

1960 to use microwave rather than cable links between cities. Modern circuitry has allowed microwave capacity to increase to supply current demand just about all the time. Even if cell phones do not wholly supersede wired telephones, the same circuitry could be applied to supply phone service on a smaller scale.

[Tony Hwang]

Hi, We're rather running out of numbers than line capacity(it's digital now)

[larry]

dsl "rides" on existing phone cable. and with folks using dsl and cable, the need for phone LINES for internet have dropped.

but there still are big problems with phone NUMBERS, there just weren't enough for all the new uses (cellphones, faxes, and other data devices). most of the US has gone to mandatory 10 digit dialing and 10,000 number blocks are no longer handed out to new phone companies. even so, plans are in place to go to four digit area codes when the number combinations available finally run out.

-larry / dallas

[trader4]

Dial up internet never caused a shortage of physical lines. The increased use of second/additional lines for internet, fax, etc did cause numbers to be used up to the point that more exchanges and area codes were needed. And except for the analog line between your house and the central office, the vast majority of phone traffic has been on digital fiber backbone for decades. Most people don't realize this and think that only with VOIP is their phone call handled as digital data. In fact, whether you use your ordinary land line with Verizon or VOIP with a cable company, the voice is digitized at your central office, transmitted digitally to wherever it;s going, then converted back to analog at the destination CO. The essential difference is the traditional land line establishes a guaranteed end to end digital connection with voice sampled at 8khz and each sample guaranteed to arrive at the other end at exactly that rate and sequence because it gets assigned its own time slot in the network. With VOIP, the digital sample is packetized and routed just like data from a website. Which is why VOIP still has quality issues as compared to a tradional line.

The main attraction in going to VOIP had nothing really to do with superior technology or doing something radically different. Instead, it was a way of avoiding tarrifs and opened up another route to competition.

[mm]

I wasn't really thinking about intercity, only about the number of lines in and out of my local exchange, and in and out of the exchanges that provide service to ISPs. And I also mean whatever resources I use when I'm on the phone.

After all, there was a reason they promoted party lines, or ONLY provided party lines some place, so that only one party out of all those sharing a party line could use the phone at the same time, that it takes resources for each phone line.

In locations where everyone had a private line, that worked I believe because they knew not everyone would be on the phone at the same time. All day is farily busy, and there are probably especially busy times, different ones for downtown versus residential areas. But not everyone is on the phone at the same time. When 20 to 40 to 80 million people in the 90's were on the phone for an extra 3, 6, 16 hours a day, how did they have enough of these resources? Again, not talking about the functions that microwaves perform.

I don't understand the last sentence.

[mm]

That's a big problem too, and the causes are pretty well known to some.

In the US and almost the entire world, the numbers used are Arabic numbers. Arabs invented these numbers many centuries ago and have controlled their production ever since. They purposely limit the supply of numbers to keep the price high. Even large corporations like AT&T can only afford to buy so many, based on a cost-benefit analysis. In other words, they can't afford to invest too much capital funding and have too many spare numbers sitting around not earning money.

Although some numbers are produced outside of Arab lands, they do that to save on the cost of shipping. But every production facility is licensed and strictly controlled the ANPB (the Arabic Number Production Board). The one or two locations which exceeded their quota were totally shut down, and the management was got no severance pay and lost their pensions.

There have been proposals to use other number systems or to create a new one specifically designed for electronics and telecommunications, but so far nothing has come of it. Some think that key corporate and govenment personnel have been bribed to prevent progress in that. I choose to think it is just the technical difficulties that have made it slow going.

[Edwin Pawlowski]

It was a huge breakthrough a few years ago when the area codes were able to use all the digits in the second position. Originally, it has to be a 1 or 0 there. There are now multiple area codes used in the same geographical region for cell phones now too.

[<aemeijers]

Most dialup calls were local calls, not intercity. And most people didn&#39;t get a second line, so number of lines was never a problem. Number of lines in use at any given time may have spiked, but the gooey GUI internet ramped up same time as analog cell tower build out, so the hardline switches were adding capacity anyway. I&#39;m sure there were problems here and there, but no more than a new office park or something opening up would cause. Ma Bell, in general, was very good at building in plenty of headroom, and service brownouts since switching from mechanical to electronic switches has been very rare, like after disasters, or in the actual disaster areas if switches get taken out.

Main cause for all the area code splits was the exponential growth of cell phones sucking up available numbers.

aem sends...

[mm]

I shouldn&#39;t have used the word "lines". I mean whatever is needed at the central stations to keep a phone call running.

Isn&#39;t that what there is a shortage of when someone gets a fast busy on a local phone call?

I&#39;m sure some resources are used in addition to my phone and the line running to my local central station.

[trader4]

What it takes at the central office to switch a local call is a central office switch. In the US, most common is the Lucent 5ESS, std version of which handles 10K lines. The switch connects local calls to local lines, and local calls going outside that CO to digital lines crossing regions. During the dial up, fax, etc line expansion days, Lucent made buckoo bucks selling these to handle the new lines. It was a big multi-million piece of hardware, that was overpriced and nothing special, but telcos bought em, right and left. It fueled Lucent&#39;s big growth and success in the 90s.

[DCT Dictator]

In my small town, yes it was a shortage.

When I was on dial-up, I used a second line. In that part of town I would get a good 33.6 on it most of the time, with frequent rocket boosts to 52000.

When I moved to another part of town that was pair-deprived, The Phone Company put my 2nd line on some mofu digital magic box that gave me 2 lines on one pair of copper. And dropped modem speed to 22000 or 14000

I outfoxed them by giving the 2nd line to the teenagers and getting a THIRD line - it was not on the magic box and I was back to 33.6/52000 speeds (someone else in the &#39;hood gave up a pair of copper and got put on a magic box, heh heh.)

DSL brought speeds topping out at 760 - woo woo. Good for a year until cable modems came along. After cable voip, I surrendered all phone company lines back to them.

[Jim Redelfs]

Lines? Yes, in some places.

Switching capacity? No. Subscribers "camped-on" for hours and days and we never broke a sweat.

Never a problem. By the time dial-up internet was at its peak, virtually all switching systems were digital. Most interoffice connectivity was (and is) via fiber optic cable.

Not a lot. The biggest factor idling ILEC (Incumbent Local Exchange Carrier) pairs was loss of customers to CATV getting into the dialtone business. It was (and is) a *HUGE* loss. :(

Yes.

No. The existing "phone-only" equipment is still used. Additional equipment is ADDED to the loop to enable DSL service.

[Jim Redelfs]

Multi-party lines were never promoted. They were a necessity due to too few cable pairs.

In the area I have serviced since 1982 (outside Omaha but still a local call to the "big" city), enough cable had been placed that party lines were no longer "bridged in the field". Instead, they were bridged in the Central Office. We haven&#39;t had any party lines for YEARS now.

The Bell System planned ahead and built its system to handle the load, before the internet was even KNOWN in the household. It worked flawlessly.

The only time a modern switching system will bog down is in the event of a disaster. If "everyone" picks-up their phone at the "same" time, a condition known as "slow dialtone" will occur. Again, the telco system is built to handle this overload, doling-out dialtone on a first-come, first-served basis.

[Jim Redelfs]

Additional lines contribute significantly to the depletion of numbers. Also, contributing to the rapid consumption of phone numbers is pagers and Custom/Distinctive Ringing numbers - where you can get up to FOUR numbers to ring a SINGLE line.

[Jim Redelfs]

You are referring to a "reorder" or circuits busy condition. A busy signal is

60 TPM (tones-per-minute). A reorder is 120.

Getting a reorder is, thankfully, an increasingly rare occurrence. It can happen for numerous reasons, the least of which is a "shortage of equipment". Sometimes the call just goes astray and hits a brick wall. Other times the call is routed through equipment, perhaps in another city, that is experiencing trouble or extremely heavy usage. Simply redialing the call usually results in success.

[mm]

Hmmm.. I wish I had known this earlier. I woulldn&#39;t have gotten off the line.

BTW, I quote myself when I don&#39;t want my comments to follow someone else, when I don&#39;t want to look like I&#39;m arguing with someone else. I do enough of that anyhow.

Thanks to all, and especially you for clearing things up, and trader4 especially for his second post which cleared things up.

This is one of those questions I&#39;ve wondered about for year.s

What follows was interesting too.

[trader4]

In the switched phone system, staying on the phone for long periods does indeed affect switching capacity and calls being very long doesn&#39;t solve any capacity issue. In fact, it makes it worse. There is some overhead in getting the call setup and then taken down again, but once established, there is no more overhead. The call going from your phone to someone elses now just involves constantly taking the voice sample from your line card in the central office and putting into timeslot 25 and then the line card serving the guy on the other side of town taking the voice sample from timeslot 25, turing it back into analog and sending it on the wire to the guy&#39;s house. That process, once set up, is fixed in hardware contained on each line card. Once told what time slot to look for, the line card is just counting timeslots, which are like a digital highway, as they go by. One card puts it into timeslot 25, the other takes it out of 25. There is no more CPU, software, etc involved.

So, if it&#39;s said a switch has run out of capacity, it usually means that there isn&#39;t enough slots to plug in more linecards to handle more lines. It&#39;s also possible that it could run out of timeslot capacity to connect all the physical lines, because I don&#39;t think they necessarily have capacity to handle having say all 10,000 lines in service at the exact same time. But the point is, whether they run out of capacity is a function of how many lines have calls going, and not how long the calls last.

[Mark Lloyd]

The only time I&#39;ve experienced phone system overload was about 40 years ago, when I was out in the country. The local switching equipment was an older pulse-dial system. It was the first snowy day of the year (in an area that doesn&#39;t get much snow) and I tried to call my parents (long distance). They had just started letting you call long distance without the operator. I would get a busy signal when all I had dialed was the first &#39;1&#39;.

[Mark Lloyd]

I do remember some areas where you could never get a v.90 modem connection.

They did that here a couple of years ago. The new area code is an "overlay", so someone just across the street could have a different area code. All local calls now require 10-digit dialing (you get a recording if you just dial 7). I don&#39;t know of actual phone number with the new area code.

BTW, It took me a couple of months to discover why my DVR wasn&#39;t dialing for the guide any more. It needed to be told to dial 10 digits instead of 7.

BTW2, you used to be able to dial local calls here with just FIVE digits. That lasted until they put in the new ESS exchange around

1990. When I bought a washer & dryer last year (from an older person at an older store), he still wrote my number down like "7-xxxx" (5 digits).