poll page

[Twey]

IPs for dialup users rotate, so if you have 20 people from AOL visiting your site, you might end up with one who can't vote because their IP at the time matches what someone else had at the time they voted.

Very unlikely, I think. How many AOL users are there out there?

Logins are the only sure way. Aside from that, IPs are good, but if people wish to cheat, they can go to another computer.

True, but there's no other way, barring logins, which are too much hassle for the average poll-voter.

simonf: Since server-side scripting will be required anyway, cookies should be sent in the HTTP headers. This is much more reliable than setting a cookie using client-side scripting.

[djr33]

Lots of people use AOL. It's very popular. With the average computer user, not web designers and such, that is.

Using a cookie is pointless.... the user can just clear cookies and they can vote again.

[Twey]

Lots of people use AOL. It's very popular.

That's my point. The more AOL users there are, the less likely it is that the Guy B both obtains Guy A's old IP address and visits the site, within one day.

Using a cookie is pointless.... the user can just clear cookies and they can vote again.

It's not pointless. It's not secure, no, but it will provide a "hey, you can't do that" factor. While there are no real downsides, it's perfectly acceptable to throw pointless solutions at a problem.

[djr33]

But they rotate randomly... you're just saying it's a big pool to choose from... that is somewhat true, but certainly not foolproof. It is unlikely, though.
What about shared computers, then? Brothers, etc?

Well... as I said before, it does nothing more than a note that "please only vote once" if the people know how to delete cookies, which isn't hard.

[pistolpapa]

Thanks for all the input, they've been very helpful.
If IP rotates around randomly, and since the population of users is probably 10s of thousands, is the possibility of hitting a user near to zero?
If that's the case, IP and email address probably provide a good bundle to prevent users from voting twice on a single day.
Beside that,
Having seen all of the "self generated random" security numbers used on google, yahoo and many other major websites, is it actually necessary or useful to put something like that before they submit the vote to prevent hackers hacking into the system and mess around?

[pistolpapa]

But they rotate randomly... you're just saying it's a big pool to choose from... that is somewhat true, but certainly not foolproof. It is unlikely, though.
What about shared computers, then? Brothers, etc?

Well... as I said before, it does nothing more than a note that "please only vote once" if the people know how to delete cookies, which isn't hard.

True, good point. What if my brother wants to vote as well. In that case, the simpliest idea may be the most applicable one. Email address verification could be the solution in this situation. However, the question is, can someone writes a software and generates many different email addresses while entering many false votes on the website. Should a security check be in place?

[djr33]

Email also has issues.
You can do things to give yourself many emails... if it's nothing more than signing up a lot at hotmail.
Also, checking their email is something more than some would-be-voters would want to do.

It's hard to figure out... IP probably is the best option... but not perfect. Still thinking....