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Darius's avatar
Darius
New Contributor III
6 years ago

White-listing IP addresses? C'mon!!!

Like many others, I've been having trouble accessing Cox Email  (specifically its SMTP server) while traveling. Cox personnel keep telling me Cox has to "whitelist" the IP address I'm using. But to me this sounds utterly ridiculous.

I can understand how one can whitelist a static public IP address. But I can't imagine anyone traveling using a static IP address. And if they're using dynamic IP addresses through DHCP, I can't see how whitelisting specific IP addresses can possibly work.

But maybe I'm missing something, and perhaps another participant on this forum can explain it to me. If you can, since I'm obviously being dense about this, please apply your explanation to the following example.

Joe and Jane and their son, Jack, are traveling from western Massachusetts to Europe for vacation. Each of them is taking a laptop, a tablet, and a smartphone (9 devices in all), all of which will be used to access Cox email. They'll start by taking commuter rail from their home to Logan airport, then fly to Heathrow, then Madrid. On the train, at each airport, and on the planes they'll be using WiFi and their Cox email. In Madrid they'll rent a car, then drive to Barcelona. From there they'll travel through southern France, Northern Italy, Switzerland, Germany, Holland, and Britain, generally stopping in several cities within each country. Again, at each of the places they stay, as well as in restaurants, etc. they will (try to) use their devices to access Cox Email. When they return to the U.S., they will fly to JFK, stay in New York a few days, then take Amtrak to Boston, and then take the commuter rail back home. Again, they will be using WiFi and Cox email everywhere they go, with any and all their devices.

OTOH, if you agree with me that whitelisting specific IP addresses is nonsense, then perhaps you can explain why so many Cox representatives disagree.

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  • Darius's avatar
    Darius
    New Contributor III
    6 years ago

    Lots of Cox representatives have sent me emails, but when they say something STUPID and I question them about it, they often don't reply. I did get one response from an agent who identifies himself as "Dustin" but he still won't explain how it can possibly be practical for Cox to white list IP addresses. Instead, he asks me to provide the following information every time my IP address changes: Country, Cox.net user ID, IP address (he doen't say public or private), is the IP address static or via DHCP (Earlier I told Cox than anyone traveling necessarily is using DHCP, so just assume DHCP all the time. But apparently reading is not one of the skills Cox requires for its tech support.)

    But based on my recent side-trip to Tibet I came up with the following calculations. I realize a DHCP server may assign the same IP address more than once, so in some sense these calculations are a worst-case scenario. But because the user has no way to know if they have the same IP address as before until after the DHCP server has reassigned the address, the customer still has to do the same amount of work

    Here's what I wrote back to Dustin:

    Just take my recent experience in Tibet as an example. I flew from Nepal to Tibet on an airplane -- this was IP address 1. Then from the airport it was 1 hour drive to Lhasa. If I could have gotten a SIM card, this would have been IP Address 2. Then at the hotel there was one WiFi network for my room and one for the dining room. These were IP addresses 3 & 4. But then when I came back to my room after eating dinner, the DHCP server for the network in my room would have assigned a new IP address, as would the dining room when I went to eat breakfast the next morning. These are IP addresses 5 & 6. Going back to my room would add IP address 7. If we assume breakfast, lunch, and dinner every day, we'd be adding 7 IP addresses daily. We spent four consecutive days in Lhasa, so we're up to 35 IP addresses. Then, as a side trip, we went to the city of Shigatse. Along the way going we stopped for lunch. Add 1 IP address for the restaurant where we ate lunch, one for the hotel room, and one for the hotel's dining room where we ate breakfast the next morning. So we're up to 38 IP addresses. Then it's back to Lhasa, and another IP address at the restaurant for lunch. Then it's back to the original hotel: add one IP address for the hotel room, one for the dining room, and another for the hotel room after dinner. So now it's 42 addresses. We stayed at the hotel another two days, so add 14 IP addresses, and we're up to 56. Then it's back on a plane, and we have 57 different IP addresses. Multiply this by 2 for my wife and me, and you have 114 different IP addresses. Now multiply this resulting product by 3 -- for laptop, tablet, and mobile phone -- and you have a possible 342 separate IP addresses. And we haven't even begun to count dynamic IP addresses that the DHCP server decides to reassign. And this is for just nine days in Tibet. I'm traveling for almost two months! So multiply this number by 6: that's 2,052 distinct IP addresses!

    ARE YOU KIDDING ME? DO YOU REALLY EXPECT CUSTOMERS TO CONTACT YOU OVER TWO THOUSAND TIMES SIMPLY BECAUSE COX CAN'T FIGURE OUT HOW TO WHITE-LIST INDIRECT ADDRESSES, LIKE EMAIL ADDRESSES, INSTEAD OF IP ADDRESSES?

    ALSO, WHY ARE OTHER COMPANIES LIKE GOOGLE AND YAHOO ABLE TO HANDLE CUSTOMERS ROAMING OUTSIDE THE U.S. WITHOUT KNOWING INDIVIDUAL IP ADDRESSES, BUT COX CAN'T FIGURE OUT HOW TO DO THIS?

    YOU'RE JOKING, RIGHT?

    And I should have added, but didn't think of it at the time:

    AND HOW IS A CUSTOMER SUPPOSED TO CONTACT YOU WHENEVER AN IP ADDRESS CHANGES IF YOU BREAK THEIR EMAIL EVERY TIME IT DOES?

    I think the above clearly demonstrates either that this Cox technician and others who have also said Cox has to white list individual IP addresses don't know what they're talking about, or that Cox really hasn't thought this through.

    • OpenBSD's avatar
      OpenBSD
      Contributor II
      6 years ago

      Cox is a United States company that provides email addresses to US based customers. It does not provide this service in other countries. It blocks all foreign IP addresses for security reasons. Unless you are using a VPN you are using unsecured wireless hotspots from foreign countries to login to Cox to retrieve your email whether it be an email client or through Webmail. You should never be doing this as your information can easily be intercepted and stolen. Whitelisting IP addresses from foreign countries is dangerous for Cox and the consumer. When using cellular data (changed sim card) then your IP will be based out of a foreign country which won't work.

      This is what I suggest. You purchase an ExpressVPN monthly subscription and then install the application on your devices. ExpressVPN is a very reputable company. You might need to make configuration changes to your email. When you connect to ExpressVPN select a location in the United States such as San Jose Texas. They have numerous locations around the world you chose from but it's important you select a US based location. This will provide you with an IP address based out of the US. Try using your email client or Cox Webmail. This is your solution.

      • Darius's avatar
        Darius
        New Contributor III
        6 years ago

        Open,

        Unfortunately, what you say is not what Cox says. It says it does provide the service in foreign countries, and it does so by white-listing. Some Cox representatives say Cox white-lists email addresses, but most say it white-lists individual IP addresses, something I find absurd. Instead, I think representatives in the latter group, all of whom have lower technical status than the ones who say email addresses, don't really understand what IP addresses are or how they're assigned.

        I agree with you about using a VPN. In fact, if you look at some other threads, you will see I made the same recommendation for the same reason as you. The VPN I usually use, IP-Vanish, is installed on all my computers. But even when I select a U.S. location for the server (Chicago, Seattle, etc.), usually I still can't access the Cox SMTP server.

        If I use a foreign SIM card in my dual-SIM mobile phone, I can still get a U.S. IP address because I have IP-Vanish installed on the phone. But I doubt this alone will solve the SMTP server problem, because it doesn't solve it on my laptop or tablet.

        I've been very happy with IP-Vanish, and think adding another VPN to the mix at this point will only make things more complex and make the real problem harder to isolate.

        I think the next step is to get someone at Cox with a technical education and who really understands TCP/IP either to explain how it's practical for Cox to white-list individual IP addresses or to admit that the lower-level support personnel are confusing IP addresses with email addresses, which are an indirect form of addressing through mail servers, and therefore are indifferent to IP addresses changing frequently.