Are Your IP Addresses Portable?

Are Your IP Addresses Portable?

Address Autonomy, Routing Security, & You

Do you know who controls the IP addresses on which your company’s network and services depend? What happens to your network if you decide to switch providers or if your Internet Service Provider (ISP) asks you to return the IP addresses they assigned to you? Let’s talk a bit about why getting space directly from ARIN may be a good option for your business.

Address Autonomy

Address autonomy means that your organization directly holds the rights for IPv4 and IPv6 address blocks, which means that those addresses were provided to you directly by ARIN or its predecessors, and can be considered portable. You can use them with any ISP(s) you choose, and should you cease service with those ISPs, you can take them with you as there is no need to return the addresses to the ISP. In contrast, IP addresses you obtain from an ISP are generally considered non-portable, meaning if you cease service with the ISP from whom you obtained them, you’ll need to return them to that ISP. If you build your network using provider-assigned addresses, and the ISP from whom you obtained them takes them back, you can be put in a very challenging situation.  In addition, since you likely are no longer a customer of the ISP, there is no guarantee you would even be contacted in the event this happened.

Routing Security

Regional Internet Registries (RIRs) like ARIN now offer routing security services like Resource Public Key Infrastructure (RPKI) and our Internet Routing Registry (IRR) which allow registrants to publish information about how those addresses may be routed. These tools allow a registrant to define which addresses may be used and from which Autonomous System Numbers (ASNs) with which they may be used. This allows ISPs around the globe to not only verify which route announcements for a given IP address block are valid, but also which are invalid. While this greatly enhances Internet routing security, it also creates a potential impact to your network if you are using provider-assigned IP addresses.

How Might this Impact You?

Let’s continue the scenario above. You run a network that has built its infrastructure using IP addresses obtained from a previous ISP; perhaps you inherited this network when you acquired the company and you never knew those addresses were obtained from a former ISP. If that former ISP publishes routing security information for the address block that you are using, the information they publish about valid uses of their IP address block may disallow it from being used on your (or your new provider’s) network. You could wake up one morning to find the addresses used on your critical infrastructure are now unusable and your network is not reachable by your customers. Think that’s going to be a bit of a headache? We agree.

Check the IP Addresses in Your Network

Here’s a quick way to check the status of who controls the IP addresses in your network: Go to ARIN’s Whois and enter an IP address being used in your network. If you see the block is a “direct allocation” or a “direct assignment” to your organization, that means the block is registered directly by your organization and is considered portable. Hopefully the information is current and accurate; if not please contact us, so we can help you update the record. That’ll help ensure you can quickly make changes to your records when necessary. If the block is a “reassignment” or a “reallocation”, that means it is space obtained from an ISP and considered non-portable.

If you are still using the ISP from whom you obtained those addresses, you’re most likely OK. You may still want to obtain your own portable addresses from ARIN, but you probably have some time to do so. If not – well, you may find yourself in the scenario described above where you could potentially wake up to find the addresses in your network are unusable. In that case, we invite you to review the steps below to find out how to get your own IPv4 and IPv6 addresses from ARIN.

Get Your Own Space from ARIN

The time is now to begin your IPv6 request. IPv6 is the addressing protocol of the future and a great place to start building your autonomy with directly assigned IPv6 space from ARIN. The qualification criteria are simple:

  • Have (or qualify for) an IPv4 block, or
  • IPv6 multi-homing, or
  • 50 projected customers within 5 years (ISPs), or
  • 200 IPv6 subnets/2000 IPv6 addresses used within one year or 13+ total sites (end users), or
  • Technical explanation as to why provider-assigned addresses are unsuitable

We also have an IPv6 transition policy which can help. Once you register an IPv6 block (it’s quick and easy), you become eligible to request a /24 of IPv4 space as frequently as once every six months to assist with your IPv6 deployment. The basic requirement to be eligible is that you use each /24 specifically for IPv6 transition, which includes things like dual-stacking key infrastructure and numbering translation pools.

We have an IPv4 Waiting List through which we distribute IPv4 addresses that become available. Applying is generally quick and easy; the main requirements are that you:

  • Have efficiently used any previous space you’ve been issued
  • Have a /20 or less (4,096 IPv4 addresses) through ARIN already
  • Request up to a /22 based on your 24-month projected need

Based on availability, we fill waiting list requests each quarter; and while we can’t guarantee how long it will take for a block to become available, it’s free to go on the list.

And of course, if you haven’t yet, we recommend you request your own ASN if you plan to multi-home, peer, or use a unique routing policy for your network.

Once you obtain IP addresses directly from ARIN, you will have address autonomy and be able to set your own routing security policies – no waking up to find out your network is down due to a former ISP’s policies. You can learn more about how you can use RPKI and the ARIN IRR to manage your own routing security. Our Registration Services staff will be happy to walk you through both the process to obtain IP addresses and to set up your own routing policies.

We hope this helps you better understand the real-world impact of IP Address Portability and provides an opportunity to avoid potential future disruptions to your business.

Post written by:

Joe Westover
Director of Customer Experience and Strategy

Recent blogs categorized under: IPv4

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