I get a report from our vendor that shows the IP addresses customers are accessing from. I'm noticing alot of duplicates that are accessing various customers accounts. Someone told me that this address is just that of a service provider. So how do I review this? Anyone know how to trace an IP address?

I use www.dnsstuff.com to get useful information about IP addresses - in particular, the "IPWHOIS Lookup" will trace the IP. It's true that your customer's IP address will trace to their service provider. You can test this yourself by putting your own IP address into the IPWHOIS Lookup". If you don't know your IP address or where to find it on your PC, the easiest way is to go to www.whatismyip.com . Then put this IP address into the IPWHOIS Lookup, and it will probably be your ISP.

The thing I would be concerned about is that even though customers may share the ISP, they should each have a unique IP address, unless you have a large volume of customers accessing their accounts from an Internet Cafe. (Yikes!)

How many duplicates are we talking about?

Edited to add: Also, are the IP addresses truly exact duplicates? Or are the last group of numbers different? ISPs own blocks of IP addresses that they assign to their customers, and therefore the numbers will be very similar because they are part of a range of addresses.

Start with the WHOIS lookup listed above. One thing to remember about IP addresses on the internet is that, although each computer has an IP address of their own, they are often translated by a router to a single IP address of the company or ISP actually providing access to the internet. This is especially true of dial-up connections.

If you have a large employer in the area and many of your customers are employees of this company, they may all appear to come from a single IP address - the address of the router performing the network address translation (NAT).

Dnsstuff.com also has a City lookup - check the IP address with that search as well.

The major area of concern would be if the IP addresses you lookup with a WHOIS search appear to originate from outside your geographic area. Any IP addresses that show up originating from Europe, South East Asia or Latin America should raise red flags and prompt additional inquiries.