one account only

per user

[FridayNight]

i created a website where i want everyone to signup only once. it is very important that a person can create only one account not more. how could i achieve that? best things i came up with (although not 100% perfect):

1) they must confirm their account by sending text message from their phone

2) i send them PIN code via regular mail (costs me money)

how else could i do that? i know i can check that with cookies but experienced users can delete cookies.

i also tried to think to put a cookie on PC which has its own age - gets older. and if its younger than 24 hours, he cannot do anything in his account. this way i could prevent switching between accounts. then i hit same problem again - someone can delete cookies and go around it. any ideas?

[vincevincevince]

Faxed or emailed copy of drivers license or passport.

Purchase of membership using credit card (warning re: disposable cards holds)

Required to telephone you for activation (or you telephone them)

Verification of name and address with other sources (electoral roll, telephone book, etc.) - no match means manual check

[FridayNight]

vince all these sound ok but the problem will be because i target couple of 100 users daily. how can i check things manually?

fax - not everyone can make copy of passport (kids, people who dont have scanner/camera)

pay $1 with cc - not everyone has cc

send SMS to me? i think thats best solution i found so far. what do you think?

[penders]

send SMS to me? i think thats best solution i found so far. what do you think?

Would your clients be OK with this? I'm not sure I would. Sending an SMS to them perhaps (with a confirm code) - but again would cost.

Prevent people with the same IP signing up? Although this would prevent anyone on the same LAN from signing up!

[FridayNight]

yeah there is no easy solution to this. i cannot limit one person to one IP. there are companies behind firewalls with 1000 employees and only one IP.

would you send SMS if you really want to join the site?

[vincevincevince]

I wouldn't send you an SMS even if there were substantial benefits to me in doing so. I don't own a mobile telephone.

[henry0]

There is perhaps a solution
I did a quick search for "driver license" database
there are a bunch of "pro" that for a fee let you search a whole country DL db
you might try to deal with those guys and figure how you could query their DB.

Will your user send you their driver license number?

Then you could use it as a login access

[Sekka]

I respect what you're trying to achieve, but its almost an impossible task.

First, there's the passive protection, things which require no effort from the user. These are things like making sure there's 1 account to an email addresss, creating algorithms to detect accounts with similar information and flag them for moderation, etc.

Then there's the active type. These can be small charges to cards, SMS codes, etc. Problem being they just add to the registration process and can deter users.

No matter what methods you undertake, people will always find a way of creating more that one account. This is a fact you are just going to have to accept. People can use their friend's phones, cards, etc. The list is endless. People can be very creative when they want something!

As VVV suggested, SMS codes and small card charges would probably be your best bet.

[FridayNight]

drivers licence wont work - lots of visitors will be 15,16,17 yrs old.

>>People can be very creative when they want something!

exactly. thats why i am afraid of! because they will WANT to create more accounts.

>>>As VVV suggested, SMS codes and small card charges would probably be your best bet.

i guess so but not everyone owns a credit card. i guess i will start with checking cookies and other data but then switch to sms as soon as possible.

[vincevincevince]

Multiple levels of verification; simple cookie / email unique test being good for up to 10 posts, 5 messages and 1 photo; go past that and you need Level 2 Authorisation (SMS or Fax or $1 pre-authorisation)... etc.

[StoutFiles]

Maybe if you could state exactly why they would want more than one account we could increase the ideas.

[vincevincevince]

StoutFiles has a good point. Could you also explain why you don't want them to have more than one account? Often the best answer to a problem is to widen things out and stop the problem occurring.

[FridayNight]

hmmmm your idea is not that bad.
thanks