The Old Joel on Software Forum: Part 4 (of 5)

Identifying users with SMS?

Hi,

What do you guys think about authenticating users via SMS?

You register, receive a short code, and must SMS it to the server to complete the registration.

That should make it difficult to "trivially reregister."

In this particular community people want their contact information public, so privacy of phone numbers isn't an issue.

Technically possible? (i.e., does the mobile number always come through?)

Alex.ro
Monday, February 2, 2004

What is SMS?

Monday, February 2, 2004

> What is SMS?

Exactly. More common in Europe than in America, and with competing standards and not everyone on the same networks (most US cell phone companies can't message Europe and v.v.) I think this isn't such a good idea.

Besides, you can't gaurantee someone has a cell phone, but you can pretty much gaurantee they have an e-mail address if they're installing software.

www.MarkTAW.com
Monday, February 2, 2004

Right.

Anyway. Email is out of the question because addresses are disposable and spamming would be a problem.

Alex.ro
Monday, February 2, 2004

email works for amazon.com

Monday, February 2, 2004

sms = short messaging system or something of that sort.. it's basically a protocol for sending back and forth packets of short messages (around 2 sentences, though that's not the limit, 500 bytes is around the traditionally known limit).

Li-fan Chen
Monday, February 2, 2004

if it's within a community where all the users have an SMS-capable phone on a network your system can reach, this sounds quite reasonable. also if you require that the user have such a phone, it verifies that condition.

on the other hand if people have land-lines, or phones on other networks, and so forth, you'll have to handle that case. back to email? if the number is small enough, human verification?

mb
Monday, February 2, 2004

I think 160 characters, including the phone number.

www.MarkTAW.com
Monday, February 2, 2004

Yes, this is a good idea.

For a system I wrote for a former employer we used this method. The user would register their number with our SMS gateway by filling in a form. They would then get SMS'd their registration code which they would then put in Step 2 of the web form.

This ensured they had a valid number for the services we provided, we were keywords. Basically the customer could send various keywords to our SMS gateway such as FIND xxxx to find someones contact details in their address list.

There was a lot to the system, if you need to know more, email me, as I spent about a year on SMS systems

Dan G
Monday, February 2, 2004

Forget about SMS, just get a good DASD manager.

Old Timer
Monday, February 2, 2004

Old Timer, just in case you aren't being sarcastic, the SMS we are referring to is the one you do on your phone.

SMS is also known as "texting", i.e. sending short text messages to and from mobile (cell) phones

Dan G
Tuesday, February 3, 2004

If you have a particular regional market, sms (or equiv) would be perfect.

SMS is popularly used by youth programs in tv, and stuff.

The other day I called a directory enquiries service; within seconds of disconnecting, I received an sms from them with the number. Completely unexpected and extremely useful. That is customer service!

In europe, smses can be massive (the phone will transparently fragment them into several smses).

Only thing is, there are internet services that provide email or web to sms gateways.

If you're writing a mobile app, then sms is great because you can tie an app to a particular device (phonenumbers aren't so easy to duplicate).

i like i
Tuesday, February 3, 2004

> Only thing is, there are internet services that provide email or web to sms gateways. <

I was just going to mention that.

btw, My cell phone will chunk up longer messages, and it has an e-mail address as well. I actually chose my provider because they have international capabilities and I have friends overseas, and plan on making more because I want to eventually see "the world."

If you're interested, from what I've been told T-Mobile (actually a branch of a European ISP as far as I can tell) and AT&T are the only two cell providers that can text message just about anyone. Verizon, Cingular, Sprint and whoever else I can't think of don't do this.

www.MarkTAW.com
Tuesday, February 3, 2004

> the only two cell providers

...in the US...

www.MarkTAW.com
Tuesday, February 3, 2004

> If you're interested, from what I've been told T-Mobile (actually a branch of a European ISP as far as I can tell

Umm, no. Actually a branch of Deutsche Telekom.

Tuesday, February 3, 2004

Ok. Thanks. All I know is t-online.de.

www.MarkTAW.com
Tuesday, February 3, 2004

Reading the title of this thread, I thought it referred to Microsoft SMS, this from a European who uses text messaging!

John Topley (www.johntopley.com)
Tuesday, February 3, 2004

It is pretty easy to send messages from one user to the next as most providers offer an email version of the SMS. So you can write to 5551234567@mobile.att.net for example. I wonder if AT&T Wireless can resolve numbers to carriers and format the email correctly.

As far as the idea, depending on where application sits in the SMS world, you might just be receiving email instead of SMS - which of course can be spoofed.

m
Tuesday, February 3, 2004

I have such terrible memory, yes the limit is 160, not 500.

Li-fan Chen
Tuesday, February 3, 2004

Why has text messaging not found its way to America yet? I'm intrigued by this. It's only the greatest invention ever, and it's very cheap compared with talking to people. (And if the receiver pays, as I hear is the case in some literally backwards areas of America, far more polite.)

Insert half smiley here.
Tuesday, February 3, 2004

cheap? nooo...
in the us, people get big packages of minutes. they're low cost.
sms is a PITA and in fact sometimes costs more money.

thus explaining why the US and Europe have completely different usage patterns.

mb
Tuesday, February 3, 2004

there are a bunch of reasons. as MB says, SMS are not cheap in the US. the competing phone services in the US do not use the same technology as do carriers in europe.
people in the US drive everywhere and blab on the phone to each other, whereas in europe (and moreso japan) people take public transport more often where it is more polite to text someone vs. yammering on the phone.

I do think the potential for SMS or some other sort of texting system in the states is huge. I am continually astounded how my younger nephews and nieces coordinate their lives through instant messaging.

Tuesday, February 3, 2004

"it is more polite to text someone vs. yammering on the phone"

I'M ON THE TRAIN!

Wednesday, February 4, 2004

WHAT. I'M ON THE BUS!!

Tapiwa
Wednesday, February 4, 2004

SMS is anything but cheap. I spend $100 a month easily. Cheap compared to calling at $1.50 a minute but not a bargain. Used in Europe because cheaper than calling cellphone to cellphone, or because parents and teachers can't listen in.

Where it's really massive is the Philipines, mainly because most have mobile phones, but few computers. Another advantage is that the message travels along a separate date stream to the voice circuit (this is because it was origninally included for technical support staff and it was only later that individuals cottoned on and it has now become the source of about 15% of phone networks revenue). Thus in the many third world countries where the voice lines quickly become overloaded or there is poor coverage, you can still communicate.

Stephen Jones
Friday, February 6, 2004

SMS however is not a reliable form of communication. If the phone is off, the message will get deleted from the server quickly. And there seem to be problems with email gateways - I've rarely lost a message sent by phone, but have quite often when sent through a computer.

Stephen Jones
Friday, February 6, 2004