landlines are interesting anachronisms

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > YOSPOS > landlines are interesting anachronisms

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

spun-off from the security fuckup megathread:

goddamnedtwisto posted:

that's the glory of backwards compatibility, flash-hooking is an example of taking a bug, turning it into a feature, then never removing that feature because half your customer base haven't upgraded their equipment since the 1970s

(the boring details if anyone are interested go like this: in the days of operator-connected calling, a line wouldn't clear down until the operator physically disconnected it. because they didn't want operators just sitting their listening to calls to see if they'd hung up (not for privacy but for financial reasons) there'd be a light next to the circuit showing whether the circuit was closed, and hanging the phone up turned that light out. the operator would then pull the plug and return it to home, clearing the line for another call

however at busy exchanges it could take several minutes for the operator to notice the call had ended and clear down, so if you wanted to make another call quickly you hammered the hook to make the light flash to make the operator notice you and clear the call. it soon became the standard way to get operator attention generally mid-call if you needed them, for example if you lost your trunk - you always see it in old movies when a call gets cut off dramatically). that's why it's called flash-hooking, you hit the hook (which was of course once an actual hook on early phones) to flash the operator's light

once automatic dialing started to come online in the thirties flash-hooking was used as the way for the phone handset to communicate with the exchange, both for dialing (old-style pulse dialing is just automated flash-hooking, and you can still dial most pots phones by hammering the hook, as everyone who's ever abused one of those freephone lines for taxis knows) and then for accessing extended features like call waiting once digital exchanges started offering that sort of thing.

a few phone systems tried to eliminate flash-hooking in the seventies as dtmf dialing started to become common, and dtmf has 16 possible values for exactly that reason, but when you're dealing with a couple of billion installed devices doing it the old way, you pretty soon give up and just go with the flow. even to this day a significant proportion of pots phones aren't even dtmf, so even though the thing at the other end of your pots line is almost certainly (absolutely definitely in the uk) a digital system of some sort it still doesn't clear down when the hook goes down, but waits for the far end to confirm that the circuit should actually be cleared. of course since the deregulation of the market and the unbundling of local loops this situation has actually got worse, because different networks have different triggers for issuing the clear-down signal, and that's what these scammers exploit.

this has been this week's effortyospost, hope you enjoyed it)

pots systems still support antique hardware which leads to some interesting legacy capabilities. post about them and other telco stuff in this thread.

# ¿ Oct 4, 2015 20:47

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# ¿ Apr 29, 2024 06:33

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

Ensign Expendable posted:

Canadian telecoms strip out caller ID and then charge you a monthly fee to put it back.

at least caller id names work in canada. in the us the carrier you are calling looks up your number in whatever lovely inaccurate db populated from cellphone contact lists they use.

# ¿ Oct 4, 2015 23:43

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

Korean Boomhauer posted:

the local cell carrier throws the name of the carrier for caller id and sometimes they'll show the carrier number rather than caller number

for outbound caller id they likely don't set names at all and the national database does it on the exchange level. for inbound caller id most carriers do nothing so you only get a name if its in your address book, or the local city/state database.

p.s. its me, im the national database

# ¿ Oct 5, 2015 00:17

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

mishaq posted:

i like how between consumer voip running over internet connections with no qos and highly compressed cellular phone codecs, making phone call in 2015 is worse quality than 1990

it sounds just as bad when the employees of lovely voip companies call from the office, a lot of the time they get landlines for some of their employees so they won't be embarrassed

# ¿ Oct 5, 2015 11:57

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

Dessert Rose posted:

and again, you also probably have access to a self-propelled generator (i.e. a car)

derailing my own thread for:
https://www.youtube.com/watch?v=sEncZHchsA4

this guy is both yospos and canadian as gently caress at machining and electromechanical stuff

# ¿ Oct 5, 2015 17:45

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

Tatsujin posted:

yeah provided the place isn't full due to a convention or some other local event

the worst is a big event at a hotel or group of hotels and even cell data is a crapshoot

i like it when they demo a fancy new phone or something with a microusb ethernet dongle because they were too cheap to rent a microcell.

# ¿ Oct 5, 2015 20:16

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

lampey posted:

411 stuff

my company did directory assistance call routing for awhile, the most interesting thing to me is that the "voice recognition" system where it prompted you for a name and then came back with a listing a short time later were actually human beings in Malaysia who were phonetically typing what you said and the server was running a fuzzy match, cuz that's WAY cheaper than licensing an actual voice recognition platform. this was notable because when reps heard a kentucky accent they just gave up, they didnt type anything because they did not have the first idea what sounds the person tried to make.

also, check out the story of the hinsdale illinois central office fire in 1988. here's the investigation report, and here's an episode of the disastercast safety podcast about it.

# ¿ Oct 5, 2015 20:32

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

Nash Regex posted:

Automated Teller Machines still use dial-up to connect for transaction authorizations.

they have cell modems now

# ¿ Oct 7, 2015 02:28

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

OSI bean dip posted:

on that note, is there any place left in north america or anywhere for that matter where you'd still find a mechanical switch?

up until ~2013 i recall denying ss7 connectivity requests for mechanical switches, so im sure SOMEONE still has them, though i believe they are all behind some sort of translation gateway now.

# ¿ Oct 7, 2015 20:04

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

goddamnedtwisto posted:

i'm sure i heard there are still some places using stowger switches because they had extremely long lines and the stowgers can take a fuckload of current, but i've no idea if that's still the case

i had a customer that was in a similar situation, i dont know what switch they had but it was old because it had to continue to operate over some gently caress-off ancient coax line with awful loss. their network would isolate every time the weather turned to poo poo. they were in a bowl-shaped area so couldnt do microwave links and were too far away to cost-effectively run fiber. i think they eventually sold to at&t on the condition that they lay fiber and replace the switch

# ¿ Oct 7, 2015 20:34

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

The Fecal Jesus posted:

I'm also pretty familiar with SMS and SMS carrier integration and I have to say, SMS is the loving worst designed protocol of all time and I cannot wait until it dies.

i somehow became the last person at my company that understands inter-carrier sms/mms hubbing. i want to die and am at the point where i scream at all customers "i dont loving care what the smpp 3.4 protocol specs say, you only get the subset of features supported by all US tier 1 carriers, if youre lucky."

# ¿ Oct 9, 2015 16:09

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

spankmeister posted:

is that when you go all SS7 and kick they asses?

actually sms is part of our push to move carriers off of ss7 to pure IP networks. instead of a billion ss7 links, establish one or a small number of gige/10gige links and use it for signalling, transport, and all related connectivity. often sms was the first IP link they established, so if we got them to do more than a lovely vpn over their office isp it was a good foothold.

# ¿ Oct 9, 2015 16:16

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

mishaq posted:

ss7 chat yessssss

the java admin gui from tekelec (now oracle hahahaha) is straight out of a 1990s hacker movie, i feel like im staring at a nuclear reactor scada console. sadly i cant find screenshots on the internet.

# ¿ Oct 9, 2015 17:53

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

mishaq posted:

a few years ago i got to walk into a lab that had to have a bunch of ss7 equipment running for testing/maintenance for some really large carriers

it was like entering a time machine, magnetic tape and massive cubes everywhere

you should see our datacenter with the tandem nonstop machine that runs the national lidb.

Alereon fucked around with this message at 21:47 on Oct 9, 2015

# ¿ Oct 9, 2015 21:44

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

fritz posted:

why were they denied, idk anything about hat stuff

we didnt want to have to support connectivity for old garbage. im not familiar with the technical details about what made it inconvenient, but given that connection parameters are hand-tuned during setup i could see not wanting to deal with weird mechanical poo poo.

# ¿ Oct 10, 2015 02:20

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

atomicthumbs posted:

(the world's most reliable network!!)

who knew three nines was a lot of loving outages? not any telco ive talked to. a lot of slas were only two nines

do you know how many times i heard "technically we forgot to negotiate an sla"

# ¿ Oct 14, 2015 02:13

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

i have never known an earthlink employee to be familiar with anything even on a wikipedia level

# ¿ Nov 20, 2015 14:36

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

so i learned a major carrier is backing out of their voip interconnects and switching back to whatever legacy telco thing they did before because voip companies overseas are even more poo poo than in the us. im not privy to the details but i guess it took a huge dedicated team wrangling peering partners just to keep call success rates in the barely acceptable range (instead of totally unacceptable) and they decided it wasnt cheaper enough to justify the effort. ss7 supremacy, diameter can suck it

Alereon fucked around with this message at 07:45 on Nov 27, 2015

# ¿ Nov 27, 2015 07:39

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

spankmeister posted:

protip: ss7 is also bad

yeah but it at least has the excuse of being designed before we knew how to do it right.

# ¿ Nov 28, 2015 00:53

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# ¿ Apr 29, 2024 06:33

Alereon: Feb 6, 2004; Dehumanize yourself and face to Trumpshed; College Slice

ota tv broadcasts are literally the opposite of landlines

# ¿ Jan 7, 2016 21:58

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > YOSPOS > landlines are interesting anachronisms