IPv6 Peering, Part 1: Questions For Your Service Provider

July 16, 2012 - 4 Comments

Today, many organizations are focusing on how to integrate IPv6 services into their Internet edge. The World IPv6 Launch has come and gone with over 3000 sites now IPv6-enabled.  In addition, the US government has directed that all agencies must enable their Internet facing services for IPv6 by October 1st, 2012. These drivers are pushing organizations to take a harder look at how to approach IPv6 integration.  My next couple of posts will examine how to interface with your Internet Service Provider (ISP).

The Internet edge is the point in your network where your organization will interface with the IPv6 Internet, and it is how customers will access your services. It is important that your ISP have the same Service Level Agreement (SLA) as your IPv4 point of attachment. After all, you are going to be running your business over both IPv4 and IPv6 for quite some time. To ensure that your ISP’s IPv6 services meet your business and technical requirements, I’ve compiled a list of questions to ask. The questions are grouped along the lines of how IPv6 is physically delivered, how the control plane is handled, and the services that are offered. The following are several example questions:


  1. Are all components of the circuit IPv6 enabled? Yes / No (Mandatory response required)
  • If yes, does the circuit support dual stacks operation of IPv6 and IPv4? (Yes / No)
  • If no, please list components of the circuit with the following conditions: List the circuit components that are not IPv6 enabled, and are not IPv6 ready. Please include the plan, with dates, when these components will be IPv6 ready and when they will be IPv6 enabled.


  1. Do you support and publish the full IPv6 Border Gateway Protocol (BGP) Routing Table? If not what portion of the BGP Routing Table do you support? Are full IPv6 global routes available to end customers?
  2. Do you host and provide the access to a “looking glass” IPv6 BGP router, for troubleshooting purposes?
  3. Do you accept and announce /48 blocks?
  4. What is the smallest prefix length you will accept?


  1. Are the QoS Policies (queuing/discard) applicable to both IPv4 and IPv6 traffic identical ? If not, please elaborate on differences.
  2. Does the provider offer DNS services which support IPv6 forward and reverse registrations?
  3. Are the DNS servers available via IPv6 transport?
  4. Do you support IPV6 Multicast?

View the full list of questions to ask your service provider.

After the peering services capability of your ISP has been discussed, it is time to get down to the details of how to implement that peering. The first question that needs an answer is how to physically make it happen: Should separate links be used or will a single link work?  This question should be an integral part of the initial discussions with your ISP.

This choice between separate links or a single link indicates how the ISP will deliver the service to the location. It all depends on where they have IPv6 connectivity in their network. The diagrams below represent some cases for how you might choose to connect to an ISP.

In some cases, separate physical links may be required from your ISP. One case that would require a separate physical interface would be if there are separate primary carriers for IPv6 and IPv4. Keep in mind here that ISPs are not interested in burning up too many ports in their points of presence (POPs). They want to service as many customers as possible using the fewest number of ports to properly deliver the service. If you choose to have separate interfaces, an alternative is to deliver a separate sub-interface or VLAN on the same physical link. All that said, there is no reason why a single link cannot be used. IPv4 and IPv6 can peacefully co-exist on the same physical link with no issues.

Stay tuned for my next post where I’ll be continuing on to next steps for interfacing with your ISP.

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  1. What To Ask From Your Service Provider About IPv6 is really useful for me.

  2. ite very interesting one, thanks for your post

  3. IPv6 not fine , because its large

    • Mohammed,

      Integration of IPv6 into a network is certainly a large project to undertake. It involves dealing with the network infrastructure, the host/server infrastructure, the applications, etc. I’ve been trying to show that by breaking the project into multiple pieces that it can be done. I will not say “easily done” because there are still lots of pieces and parts to deal with even if the project is broken down into component projects. However, by breaking the project into smaller projects, you do get problems that are easier to manage and implement. In the interest of narrowing down the scope of your comment, is there a certain aspect of IPv6 integration that concerns you?