Prevent spam and duplicate votes from same user

[3rownz]

Is your feature request related to a problem? Please describe.
I find it frustrating that when using a public link there is not way to prevent spam/duplicate votes from the same user. the only prevention included is a simple name input, this does nothing but identify a vote.

Describe the solution you'd like
Intergrate a ip address check or email input or even both before sending to the vote screen:

• So first check the current user's ip address is not stored with voter info.
• If it isnt route to email input screen - user inputs email address.
• Sent email (similar to invited user contacts email).
• Email link sends to vote page, where ip address is stored on form submition.

Describe alternatives you've considered
Another option could be to check and add a browser cookie as an alternative to ip check or maybe as an addition.

Additional context
The inclusion of all three would still not make it perfect prevtion of spam/duplicate votes, but would greatly decrease the chances of some one altering the results. Perhaps have all three of these features as options on creation of the poll.

[dartcafe]

@3rownz
The notification is designed as voting events are stored in a queue. If the same event (same poll, same user) exists unprocessed in the queue, it will not be added again. Every 5 minutes the queue gets processed and notifications are sent. Then new or changed votes will be added again, to get informed about events in the subscribed polls. A compromise between less notification and short term notifications.

In the future, we will use the NC notification system, so this will be mainly handled by core.

• We do not deal with IP addresses
  Storing IP addresses is not helpful, because most people use dynamic IP addresses and we have to handle IPv4 and IPv6.

• We do not use any cookies
  Cookies are confidential due to some privacy regulations in different countries. Additionally your solution is rather complex.

• Storage of personal information follows the rules of preventing of data collection (if not necessary).
  Email addresses for public votes is a to do, but will stay optional. They will only be used for notifications in public votes.