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Communications Cellphones News

Why Text Messages Are Limited To 160 Characters 504

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.
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Why Text Messages Are Limited To 160 Characters

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  • by loshwomp ( 468955 ) on Monday May 04, 2009 @12:24PM (#27816985)

    The real question should be "Why are we still using ancient text messages instead of regular email?" All of my friends in Japan regularly do full-on email on their phones, and only have a vague-if-any notion of what a regular "text message" is elsewhere. 160-character limit? That is *so* 1990s.

  • by Anonymous Coward on Monday May 04, 2009 @12:26PM (#27817019)

    Piruriparopirurora

  • by Krneki ( 1192201 ) on Monday May 04, 2009 @12:30PM (#27817083)
    Because you can charge for SMS, while emails needs full Internet access. And they don't want to give us cheap Internet access.
  • by drsquare ( 530038 ) on Monday May 04, 2009 @12:32PM (#27817107)

    Because phone Internet access is incredibly expensive compared to text messages. Japan isn't a good example, they love any expensive gimmick.

  • Bad article (Score:5, Insightful)

    by Sockatume ( 732728 ) on Monday May 04, 2009 @12:39PM (#27817207)
    The article states outright that the 160-character limit came before Hillebrand's "typewriter experiment", and that the experiment actually about because of an argument between Hillebrand and a coworker about whether 160 characters was sufficient for a sensible message. This meshes with what we already know about SMS, namely that it could never have been much more than 128 characters for technical reasons. Quite why the article structures its opening to suggest that Hillebrand pulled the number out of his arse after some typewriter time is a mystery.
  • Re:biocompression (Score:1, Insightful)

    by Anonymous Coward on Monday May 04, 2009 @12:44PM (#27817281)

    You are so going to get into trouble having that attitude.

  • Re:SMS vs email (Score:2, Insightful)

    by CodingHero ( 1545185 ) on Monday May 04, 2009 @12:47PM (#27817331)
    As mentioned in the article summary above, SMS also uses a channel that isn't used for much else other than miscellaneous call and signal strength data. It is also my impression that text messages have no guaranteed timeframe for delivery, as said miscellaneous data takes precedence. So it seems to me that since SMS takes advantage of facilities that would still exist in its absence, charging $0.20 per message (or even anything at all) is akin to a ripoff. See also: http://gthing.net/the-true-price-of-sms-messages/ [gthing.net]
  • by Lumpy ( 12016 ) on Monday May 04, 2009 @12:49PM (#27817353) Homepage

    Because the packet data plans are insanely overpriced!

    In the usa it's all about raping the consumer.

  • In other words (Score:2, Insightful)

    by EmagGeek ( 574360 ) on Monday May 04, 2009 @12:49PM (#27817373) Journal

    Find a way to charge people a nickel to do something that we can provide them at no additional cost to us.

    I love capitalism :)

  • Re:SMS vs email (Score:2, Insightful)

    by LordLimecat ( 1103839 ) on Monday May 04, 2009 @12:50PM (#27817375)

    SMS is clean: no risk of having to retrieve large attachements, hardly any spam due to sender costs

    wouldnt the sender of spam have an unlimited texting account or use some email-to-text service?

  • Re:SMS vs email (Score:3, Insightful)

    by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Monday May 04, 2009 @12:50PM (#27817393) Homepage Journal

    Two words in response: Watermelon rutabaga.

    My response is only slightly more inscrutable than yours. Care to explain how one or two packets being worth more than thousands of packets can be explained by the fact that all the data has to be carried by towers? Text messagers should be encouraged. You just ratchet up the base rate, and give away text messaging. That way you save money when people text, and they thank you for it. Then they do more texting, and you can use less-performant towers because you're carrying less data. The cellphone providers have driven people to use as many minutes as possible and then they want to charge us for it, which is why more and more people are looking for alternate phone services. The only reason we don't have THOSE is due to government collusion (there is no fucking way all these AT&T mergers should ever have been approved — why did we ever split up Ma Bell in the first place?)

  • by DomNF15 ( 1529309 ) on Monday May 04, 2009 @12:51PM (#27817399)
    and it costs a lot less to upgrade their entire cell network, even if they are using vastly more expensive technology.
    In fact, Japan land area: 377,835 square km

    USA land area: 7,689,027 square km - you can fit quite a few Japans inside the USA.
    This is the prime reason why US cell networks are so slow to get the latest and greatest...
  • Re:I'll Be Damned (Score:5, Insightful)

    by BrokenHalo ( 565198 ) on Monday May 04, 2009 @12:55PM (#27817451)
    You might want to make two posts next time. Character count with space = 208.

    Don't start me. I know any number of supposedly intelligent people who are apparently incapable of reading a simple email containing a series of questions or points.

    They will respond to the first question, but anything after that is consigned to /dev/null. I occasionally get cranky about it and send off a series of single-sentence emails, with the query in the sentence line.

    I don't know whether it's my circle of acquaintances, but the worst offenders seem to be MBAs. (Maybe it really does mean Master of Bugger-All). Or maybe it's just the Simpsonisation of society that gives it the attention span of a flea.
  • by julesh ( 229690 ) on Monday May 04, 2009 @12:59PM (#27817523)

    If 160 latin characters can be compressed into about 128 bytes, how many hanzi can fit? Maybe forty?

    Probably more like 64; two bytes is usually enough to represent just about anything. A clever encoding scheme might squeeze as many as 80 in. OTOH, each of those characters carries more information than a single character of English text. Not sure about Japanese, but most common Chinese words [pandagator.info] are only two characters long, so being able to include fewer characters shouldn't be a real issue.

  • by tirerim ( 1108567 ) on Monday May 04, 2009 @01:04PM (#27817599)
    Because you only get 256 different words that way? There are a lot more commonly used words than that, and then you're left with no way to spell out the uncommonly used words, either. You could use two bytes per word... but that's basically what txtspk is anyway, only with variable compression, such that the most common words get compressed down to a single byte (often as part of a longer abbreviation).
  • Comment removed (Score:3, Insightful)

    by account_deleted ( 4530225 ) on Monday May 04, 2009 @01:14PM (#27817755)
    Comment removed based on user account deletion
  • by TheRaven64 ( 641858 ) on Monday May 04, 2009 @01:20PM (#27817843) Journal
    Kanji is much denser than English text. You need a minimum of 4 characters plus a space per word in English (the average is closer to 5-6, meaning 7 bytes - 5.25 octets with a 6-bit byte). In contrast, a lot of common words in Chinese or Japanese need only one or two ideographs. These can all be represented in a 16-bit character set, and probably closer to 14 bits. This means that the 1024-bit header for SMS can carry something like 70 words in Japanese or Chinese, but only about 25 in English.
  • by Anonymous Coward on Monday May 04, 2009 @01:21PM (#27817879)

    Actually, in Korea, I can fit 90 characters in a text message. Whether I use English or Korean is up to me - it's certainly more space efficient to use Korean, since one Korean 'character' is actually a whole syllable.

    Most phones that I've seen here will simply switch automatically between an SMS and a 'long message' of 2000 characters. I haven't figured out if those are more expensive, though, since my Korean's not good enough... :P

  • Re:In other words (Score:3, Insightful)

    by MrMista_B ( 891430 ) on Monday May 04, 2009 @01:24PM (#27817919)

    Are people willing to freely pay that nickel? Do they choose to pay that nickel of their own free will?

    Yes.

    So why the snark?

  • Comment removed (Score:5, Insightful)

    by account_deleted ( 4530225 ) on Monday May 04, 2009 @01:30PM (#27818017)
    Comment removed based on user account deletion
  • Re:I'll Be Damned (Score:5, Insightful)

    by bennomatic ( 691188 ) on Monday May 04, 2009 @01:44PM (#27818255) Homepage
    You're totally right.
    • people respond somewhat well to bullet lists
    • people respond somewhat well to numbered lists
    • give people a paragraph or two and they will either ignore it, or worse, call you.
  • Re:I'll Be Damned (Score:3, Insightful)

    by BrokenHalo ( 565198 ) on Monday May 04, 2009 @01:50PM (#27818343)
    Harvard has a bad rep for its MBA degrees. That doesn't AFAIK apply to its "real" degrees.

    (I'll probably attract flames for that quoted word, so let's just say that's my prejudice and leave it at that.)
  • by ChrisMaple ( 607946 ) on Monday May 04, 2009 @02:08PM (#27818613)
    To shorten your English samples:
    I woke up. -> I woke.
    I ate in the afternoon. -> I lunched.
    I am talking on the telephone with my friend in Tokyo. -> I'm phoning my Tokyo pal.
  • by pwfffff ( 1517213 ) on Monday May 04, 2009 @02:39PM (#27819073)

    Why bother to sub a 1 for the I if you're just going to go nuts with an L at the end?!

  • by Anonymous Coward on Monday May 04, 2009 @02:53PM (#27819293)

    $20-$30/month for unlimited texting, or 20 cents a message. I can't see how they justify the costs...especially if you pay for a data plan. So, I've decided that anytime I receive an unsolicited text message, I will call my service provider and challenge the charge. It has to cost more than 20 cents to listen to a customer complain. I figure if we all do it, they'll change their plans and allow you to NOT receive text messages if you don't want them ... and who needs them when you can just e-mail or call the person?

  • by Shin-LaC ( 1333529 ) on Monday May 04, 2009 @03:11PM (#27819557)
    Posting to undo erroneous mod. Will also undo the other three mods I did on this page. There really ought to be a "cancel mod" button.
  • by UncleTogie ( 1004853 ) on Monday May 04, 2009 @03:14PM (#27819601) Homepage Journal

    Actually, I find the honesty refreshing.

    The ones I have a low opinion of are the parents that insist "My child is really smart and beautiful! It's the school/teacher/environment to blame for my child's inability to multiply single-digit numbers without a calculator!"

    Mayhaps if more parents took a realistic view of their crotch-fruit, we wouldn't have the self-absorbed, narcissistic bozos who feel entitled to do whatever they want.

    ...and before anyone asks, yes, I *am* a parent.

  • Re:BINGO! (Score:3, Insightful)

    by earlymon ( 1116185 ) on Monday May 04, 2009 @03:16PM (#27819651) Homepage Journal

    OK, cool, I can see that. At the same time, I honestly wonder if it worked that well or if it was just part of IBM's sale's pitch.

    In any case, I think it's pretty safe to say and bet that any of the BUNCH machines were better than the IBM - technically. But just like the Windows user's adherence to that OS because he has less change to cope with (insofar as his belief system supports) - if you did change, you were happier.

    Can't fight marketing. You don't have to have the #1 product. Having the #2 product with a better rap and better positioning is often the way companies win.

    Cheers!

  • by EvolutionsPeak ( 913411 ) on Monday May 04, 2009 @04:32PM (#27820775)

    Well it's easier for the GP since it is some other guys crotch-fruit, not his.

  • Re:I'll Be Damned (Score:5, Insightful)

    by theaveng ( 1243528 ) on Monday May 04, 2009 @05:44PM (#27821879)

    >>>The cost is zero to the telcos, but the profit is gravy. It is a complete rip-off scam to the consumer.

    I disagree. The retail cost is whatever the market will bear. This idea goes all the way back to John Smith, and is not necessarily tied to the actual cost of the good. You might call it a "ripoff" but it's a ripoff that customers *voluntarily* enter into. They could just as easily decide not to do texting (as I do).

    The flip-side of this is that money collected from all these texters helps subsidize my (and your) voice calls. I pay just 18 cents a minute, which is a real bargain considering wired phone calls in 1990 used to be 25 cents a minute. Simple inflation says the price should have increased to 45 cents, but instead prices have dropped and with the added benefit of being wireless. Without texting the voice calls would have to be significantly higher in order to cover the maintenance/electricity costs.

    Anyway it could be worse.
    The cellphone company could be run by Congress (like Amtrak).
    In which case you wouldn't have a choice;
    instead they'd suck the money from your paycheck.

    With today's private companies I can choose to buy or not buy, text or not text, make calls or not make calls. I control my own destiny and how much I want to spend (or not spend).

  • Comment removed (Score:5, Insightful)

    by account_deleted ( 4530225 ) on Monday May 04, 2009 @07:13PM (#27823355)
    Comment removed based on user account deletion
  • Re:I'll Be Damned (Score:5, Insightful)

    by Mr2001 ( 90979 ) on Monday May 04, 2009 @08:09PM (#27824213) Homepage Journal

    I disagree. The retail cost is whatever the market will bear. This idea goes all the way back to John Smith, and is not necessarily tied to the actual cost of the good.

    I think you mean Adam Smith, and I think you're misreading the GP. Cost != price. The retail price is whatever the market will bear, but the cost of providing SMS service is virtually zero.

    You might call it a "ripoff" but it's a ripoff that customers *voluntarily* enter into. They could just as easily decide not to do texting (as I do).

    It's awfully glib to say we shouldn't be upset about being ripped off just because we have a choice. In a free market, with healthy competition, the price of goods and services should fall to just above their actual cost. That obviously isn't happening with SMS: customers would like to pay less, but no one is offering SMS for less, even though it costs almost nothing to provide. Doesn't that suggest a market failure?

    Anyway it could be worse.
    The cellphone company could be run by Congress (like Amtrak).
    In which case you wouldn't have a choice;
    instead they'd suck the money from your paycheck.

    Or perhaps it could be run like the US Postal Service, in which case it would provide world-class service at a far lower price than any of its competitors. The USPS will carry a physical envelope from my doorstep to someone else's doorstep, thousands of miles away, for less than the price of 3 text messages.

    (I'm not saying we should nationalize cellular companies - just pointing out that services set up by the government aren't inherently inefficient as you seem to be implying.)

  • Re:I'll Be Damned (Score:3, Insightful)

    by Mr2001 ( 90979 ) on Tuesday May 05, 2009 @05:25PM (#27837935) Homepage Journal

    I have Verizon and pay $4/month for 400 txt messages...

    That's $0.01/message.

    Correction: that's $0.01 per message if you use exactly 400.

    If you only use one, it's $4 per message.

    And if you use more than 400, you pay an extra 20 cents for the 401st message (and each message after that).

    Why is there no option to pay a reasonable per-message fee without having to commit to buy more messages than you actually use?

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