Look into the req.ip field in more depth and determine if it is an adequate way to uniquely identify users.

[Stephan Halarewicz]

There are numerous ways to get the IP address off of the request object.

The header x-forward-for will hold the originating IP address if a proxy is placed in front of the server. This would be common for a production build.

• req.ips wwill hold an array of IP addresses in x-forward-for header. Client is likely at index zero
• req.ip will have the IP address
• req.socket.remoteAddress is an instance of net.socket which is used as another method of getting the IP address
• req.ip and req.ips will work in express but not with other frameworks

[Evan McNeely]

This is similar but different to issue #38 . Consider handling these together.