Trouble with Static IP Addresses

The Trouble with Static IP Addressesnetwork-cable-ethernet-computer-159304

A recent experience with a bad IP address was an eye opener. It caused a considerable financial loss for the business.

First let me explain what is an IP address…

Every device you have that is connected to the Internet or a network has an IP (Internet Protocol) address. Whether it is a smartphone, computer, printer, surveillance camera, etc. it must have an IP address to be joined to a network. On any given network, your IP address must be unique. A common IP address of home routers is

Most of the time IP addresses are assigned by a device called a DHCP (Dynamic Host Configuration Protocol) server. For home users, this is embedded in your router. Many businesses use this function in a server. Your home or business network is also assigned an IP address by your Internet Service Provider (ISP). The address handed out by your ISP usually changes every day or so, but sometimes it can be more or less frequent.

IP addresses on your local devices in your home or business such as on your computer or printer are called private IP addresses. The IP address assigned to your business or home on the Internet is considered a public IP address.

Why would you need a public static IP address…?

Sometimes you need to have a public IP address that never changes. You need a static IP address. A static IP address allows you to host a web site or email server or security cameras. A static IP address allows your web site or email server or security cameras to be found on the Internet.

You have a fixed mailing address for your home or business. The combination of our business address (6900 Tavistock Lakes Blvd, Suite 400, Orlando, FL 32827) is truly unique. Your full business or home address is truly unique as well. Enter your full address into Google Maps and you only get one choice. That is how to think of a static IP address.

Because there are a finite number of public static IP addresses available so your ISP will charge for a static IP address. Typically, the cost is $10 a month, but that can vary. You can buy one public static IP address or a block of a few up to several. There are currently 588,514,304 static IP addresses available.

Here is where the trouble starts

We had a business that needed to implement an in-house email server. We were on a tight deadline. The first task we completed was ordering a public static IP address from the business owner’s ISP. The next day the ISP sent a technician on site to setup the static IP address. We proceeded with the email server setup and all was good.

Or so we thought. The business owner started getting email messages that bounced back. We checked our work and confirmed we had done everything correctly in regards to email server setup and email domain settings.

We quickly figured out that the public static IP addressed was blacklisted. This means that the address was on a list referenced by email providers to check for SPAM email.

A quick call to the ISP netted the business a new static IP address. A follow up check while we were still on the phone revealed that the new address was also blacklisted. This process went on for nearly an hour. The ISP would issue a public IP address and it would fail a blacklist check.

Ultimately we ended the phone call and the ISP emailed us when they had found a good IP address. This process took a few hours.

The moral of the story…

What can cause a seemingly new static IP address to be placed on a blacklist? One cause could be that the former owner of the IP address was up to nefarious deeds such as sending SPAM. Another cause could be that the previous owner had an infected computer on their network that was sending out SPAM as part of a botnet.

We researched the cause of our problem. The ISP had previously only provided Internet service to home users before branching into business service. They had a policy of not allowing home users to host email servers. They submitted all their IP addresses to a SPAM database as addresses not allowed to send out email. Now that they are providing service to businesses they do allow the use of email servers, but they haven’t removed their IP addresses from the SPAM database.

We now have a process of checking an IP address issued from an ISP before we place it into use. If you are ordering a public IP address for your home or business give us a call and we can assist you with checking if it has a clean bill of health before you accept it. Even if you don’t plan on hosting an email server it is still important to have an IP address with a good reputation. You can check an IP yourself by using these tools.

MX Toolbox Blacklist Check

Robtex IP Reverse DNS and Blacklist lookup

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