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Why Text Messages Are Limited To 160 Characters
The LA Times has a story about Friedhelm Hillebrand, one of the communications researchers behind efforts to standardize various cell phone technologies. In particular, he worked out the 160 character limit for text messages.
"Hillebrand sat at his typewriter, tapping out random sentences and questions on a sheet of paper. As he went along, Hillebrand counted the number of letters, numbers, punctuation marks and spaces on the page. Each blurb ran on for a line or two and nearly always clocked in under 160 characters. That became Hillebrand's magic number ... Looking for a data pipeline that would fit these micro messages, Hillebrand came up with the idea to harness a secondary radio channel that already existed on mobile networks. This smaller data lane had been used only to alert a cellphone about reception strength and to supply it with bits of information regarding incoming calls. ... Initially, Hillebrand's team could fit only 128 characters into that space, but that didn't seem like nearly enough. With a little tweaking and a decision to cut down the set of possible letters, numbers and symbols that the system could represent, they squeezed out room for another 32 characters.
it also happens to be precisely 2 lines of text on a good old 80 character wide terminal.
is the bastard offspring of the union of the hexdecimal and the decimal, literally 0xF*10
fixed that for you
Are you joking?
0x10*10...
The account's set up with your phone number, uses the same user identifier, travels with the phone number, and there's a billing infrastructure for it. Meanwhile the vast majority of phone users don't even have packet data plans. It's operator inertia, basically.
No kidding!!! What do you say at this point?
80 characters (bytes) just happened to be how many punched you can normally fit on a standard punch card.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Differences:
- SMS is available: it's built-in, e-mail is not present on every phone and relies on a third-party service provider plus settings
- SMS is faster: because there is no GPRS/TCP/IP/SMTP/IMAP/POP connection and transfer overhead
- SMS is clean: no risk of having to retrieve large attachements, hardly any spam due to sender costs
- SMS is cheaper: most plans offer a sufficient amount of free messages a month for most users, e-mail requires an additional GPRS data plan
YMMV but SMS is not as bad as some people claim.
For those that were wondering how they got 160 characters into 128 bytes (6.4 bits/char), they didn't. The increased the length of the frame to 140 bytes, which is is 160 characters using a 7 bits/char. Curiosity forced me to look this up, expecting to find some snazzy compacting algorithm for a non power-of-two alphabet.
Here's what's ridiculous. I have a Blackberry, and do not have an SMS plan with my carrier, thus each text costs me 25 cents to send. Receiving SMS is free and unlimited. I have an unlimited data plan for Blackberry, so I simply send emails using the carrier email SMS gateways for "free". The only downside is that the recipient cannot directly reply to my message. Here's the stupid part. The amount of bandwidth, processing, and inter-service gateways my emails have to pass through must require at least 100 times the resources of sending an actual SMS. The final kicker is that even if I keep my actual message under 160 chars, they are usually broken up into more than one SMS message because of the header attached by the SMS gateway that contains my email address, etc.
Better known as 318230.
And a full-screen terminal (3270, etc.) is really just 25 punch cards. You press "Enter" and they get submitted. Your batch processes and the system returns you 25 punch cards which your smart 3270 punch card reader/editor displays for you.
Punch cards are based on the civil-war-era dollar bill because there were already machine to count and stack dollar bills.
Punch cards were IBM's most profitable product ever until the introduction of the IBM PC.
"Why are we still using ancient text messages instead of regular email?"
I can't speak for everybody, but I use a Tracfone. Talking costs $.10 a minute, but text messages only cost me $.03 per message. I pay $6 per month for my phone (it's mostly for emergencies), and communicating by text message helps to spread out the amount of use I can get each month. One thing that's even better is the fact that my wife or I can text each other from our e-mail. It's easier if I'm at the store and my wife texts me to pick up eggs, milk, what-have-you, so I'll only use $.03 to get the same message I would have had to stop and answer the phone for $.10.
Taking guns away from the 99% gives the 1% 100% of the power.
You'd like to believe it was your Jesusphone being that intelligent, but in reality, the SMS standard has supported message concatenation for at least the last ten years, if not since its inception. My Nokia 2110e could turn it on and off, and you'd see the little counter for "remaining characters" go from 160 to 470 or so.
Well.... I haven't seen a 160 character limit in Europe for years because *every* handset automatically splits/reassembles arbitrary length messages. And the cost hasn't been a factor as I haven't seen a call-plan that charges for text messages in years either...
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The ruts in Roman roads are 4'whatever wide because that's how wide the cart wheels were spaced.
Cart wheels were spaced that wide because that's what fits around two horses.
The first railways used horses to pull the loads.
The width of a horse hasn't changed since Roman times, so the width is the same.
Here I was, in my dumb ignorance caused by blind experience on the field, thinking that the limit was actually caused by the magic 255 number less protocol overhead (result: 140) plus 7-bit encoding compression (result: 160).
http://dilbert.com/2010-12-13
If anyone is interested - the way they got more characters available was by cutting down characters to 7bits instead of the normal 8, thus limiting the possible characters to 128.
1120bits/7bits = 160 characters.
or else!
Snopes says undetermined on that one... http://www.snopes.com/music/media/cdlength.asp
Mind you, my iPhone has no 160 character limit, I'm sure other smart phones just piece together the rapid recieving of messages in to one while the "dumb" phones display them in 160 character chunks.
I absolutely hate when my iPhone friends text me. I end up getting this stream of text messages that are received backwards and cause a lot of hassle just to understand the message on my cell phone.
It would be nice if the iPhone limited texts to 160 characters for those of us without the jesus phone (or a smart phone that supports it).
Oh wait... that's probably why Jobs did that :)
The number of characters that can be printed across CowboyNeal's buttocks. He has a very long yet narrow ass that contains a tattoo of every sig in slashdot.
Said, "It's just like dice but it's got more sides And it tells me who lives and who dies"
In AMPS, the cell phone technology being described, there's a 3600 baud control channel shared between all the phones in a cell. Text messages had to be crammed into that. Voice was analog FM, with the control channel telling the handsets which voice channel to use.
That's why SMS is so data-limited. The data channel was tiny.
I don't know what's actually more popular, but I have seen two ways for Chinese input into phones. There are probably more, I'm by no means an expert.
1. Handwriting recognition on a touchscreen, like a PDA. This, I saw a few years ago, I imagine it's a higher-end option.
2. Recognition based on strokes. It's like predictive text. There are only so many directions to draw the a stroke that combines to make the glyph. So you just pick them off the phone, I guess there's a standard pattern, like starting from the top left stroke.
Hopefully someone who knows more can provide more detail.
Technically, 160 is the number of bytes in a single GSM packet.
Which is usually used to transmit 20ms of audio. Or a single text message. If we assume your cell call costs 1 ct per minute, a single SMS should cost 0.000333ct.
Hillebrandt is not the only one claiming to have invented SMS. Another contender is Finnish Matti Makkonen
Karma: Good! Napster: Baad!
Actually, SMS is like a "stowaway" of a signal your cell must receive from time to time.
So the "real" cost of a SMS is 0.000000.
This is a broadly known fact.
Years ago, here in Chile anyway, SMS where free of charge.
Now is pure profit. (about 8ct/SMS at current exchange)
I don't know about that, just earlier today I was reading a post from a slashdotter from Norway that said cellphone modem connections don't count as broadband by some technical definition yet the Verizon Rev A, AT&T 3G and Sprint 3G (not to mention their pilot 4G) network all fit his definition. Cost is still high, especially when you consider the low 5GB caps but with a modern smart phone the US networks are plenty advanced. Personally I love an OS 4.5 Blackberry and Safari on the iPhone 3G is very cool for pages that Opera mini doesn't parse well.
Broadband is on one hand defined as a multiplex connexion, http://en.wikipedia.org/wiki/T-carrier T1 for instance, on the other the FCC defines it as a >200 kbit connection (either up or down). OT, but hopefully informative.
(NOT posting as AC, and proud of it)
All those moments will be lost in time, like tears in rain. Time to die.
UTF-16 is much better than UTF-8 for encoding asian scripts. UTF-8 needs 3 bytes per code point in that range, while UTF-16 needs only two.
If the geiger counter does not click, the coffee, she is not thick.
It's a long fail.
'To lunch' has been a legitimate verb far longer than people have been, *ahem*, texting.
/...
My understanding is that GSM protocols were largely inspired by ISDN protocols. ISDN had (has) the same short messaging capabilities on its 'D' channel which is the out of band signaling channel (2B+D). Most ISDN phones and Mac/PC softphones had messaging feature built-in.
1) Developing relationships. It's amazing how far a few seconds of idle chat can go to put a human side to your interactions with the people you need things from.
It's also amazing how annoying your idle chatter can be to a busy person who is trying to do things for you. Email is asynchronous, so the busy person can attend to it when they have time. A phone call is always an interruption.
2) Forces you to be concise: If you have 30 seconds to ask for something - you'll be forced to get to the point more quickly.
In my experience, those most likely to use the phone are also the most likely to prattle on and on about completely irrelevant topics.
Give me Classic Slashdot or give me death!
Snopes. It also mentioned the space shuttle that another responder mentioned.
The retail cost is whatever the market will bear. This idea goes all the way back to John Smith
Adam Smith?
Without texting the voice calls would have to be significantly higher in order to cover the maintenance/electricity costs.
Wouldn't the voice calls also cost whatever the market would bear, as you assert for text messages, and if not, why is this a special case?
I am not a crackpot.
Well let's see. You claim the cost per text is zero. Obviously that's not true since maintenance plus electricity for the towers costs money, but it's obviously quite cheap. So anyway..... my cellphone provider charges just 1 cent per text. That's about cheap as a plan can get, since you can't charge less than a penny (half-pennys were discontinued a long time ago).
That's impressive. Who's your cell phone provider and what sort of package do you need to get that deal? The carriers I know of charge 15 to 20 cents per message (although you can get a discount on the first N messages with a package).
That was hiliarious. The U.S.P.S. is losing money year-after-year and only survives because of taxes drawn from out of our paychecks (see my previous post).
No, that's completely false. If someone told you that, they were lying.
"The Postal Service is a self-sufficient agency. The cost of postal operations, including the costs to extend service to an additional 1.2 million new deliveries in 2008, must be financed by the revenue generated from the sale of postal products and services." (link)
And when I have something important to ship, I definitely don't use the government company. Instead I go to one of the private companies because (1) they cost less (2) they don't lose stuff and (3) if they did it's insured for free (upto $100). Oh and (4) they are the only ones who offer overnight package service; the government does not.
And when you need to send a letter, return a warranty card, pay a bill... do you use FedEx or UPS? I sure hope not: it'd cost much, much more and probably be less reliable. Sending packages is one thing, but private companies simply cannot provide the same service as the USPS for regular mail.
I can't think of a single government company that is as efficiently-run as its commercial counterpart.
That's because you're deliberately ignoring the prime example.
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