As the internet steadily runs out of IPv4 addresses, making the shift from IPv4 to IPv6 is a matter of when, not if, and already a multitude of organisations and service providers are making the transition.
It’s in your interests to start planning the implementation of IPv6 sooner rather than later, allowing the time to iron out kinks, minimise downtime and compete successfully with others who have made the change.
Here’s a set-by-step guide to transitioning from IPv4 to IPv6…
The art of coexistence
The good news is, although there are few, if any, IPv4 addresses available, IPv4 and IPv6 are set to coexist for some time. The bad news is, eventually all business, providers and users of the net will need to transition to IPv6.
So how do you make the change? In the interim it comes down to coexistence and here are the most common methods of handling both IPv4 and IPv6.
The three most common methods
A dual stack network involves having all nodes capable of handling both IPv4 and IPv6. It allows both systems to run simultaneously without interruption.
In the words of Technopedia: “When a node within a dual stack network receives traffic, it is programmed to prefer IPv6 over IPv4 traffic. In the event that the traffic it receives is solely IPv4, then the dual stack node is capable of processing it as well”.
Dual stacking is the preferred method of ISP providers and business alike, but it’s not the only choice.
Tunnelling takes various forms but the outcome is the same; it allows information to be processed without the user feeling a glitch. Cisco explains it best when they describe the various forms of tunnelling available:
• Manual IPv6 -over-IPv4 tunnelling is an integration method where an IPv6 packet is encapsulated within IPv4. This requires dual-stack routers.
• Dynamic 6 to4 tunnelling is a method that automatically connects IPv6 islands through an IPv4 network , typically the Internet. The 6 to 4 tunnelling method dynamically applies a valid, unique IPv6 prefix to each IPv6 island, enabling fast deployment of IPv6 in a corporate network without address retrieval from ISPs or registries.
• Intra-Site Automatic Tunnel Addressing Protocol ( ISATAP) tunnelling is an automatic overlay tunnelling mechanism that uses the underlying IPv4 network as a link layer for IPv6 . ISATAP tunnels allow individual IPv4 or IPv6 dual-stack hosts within a site to communicate with other such hosts on a virtual link, creating an IPv6 network using the IPv4 infrastructure.
• Teredo tunnelling is an IPv6 transition technology that provides host-to-host automatic tunnelling instead of gateway tunnelling. It passes unicast IPv6 traffic when dual-stacked hosts (that is, hosts that are running both IPv6 and IPv4) are located behind one or multiple IPv4 Network Address Translators.
Proxying and translation or NAT Protocol translation
This involves the use of an NAT protocol translation device that basically converts IPv4 to IPv6. In this instance a host with IPv4 sends packets of information to a host with IPv6.
The NAT protocol translation device converts packets to IPv6. It strips down the IPv4 header, converts it to v6 and works in reverse going the other way.
Making the transition from IPv4 to IPv6
So your business has identified it needs to make the shift, well what happens next? According to Network World it’s a four-step transition that requires the following milestones.
The first step involves ascertaining exactly the cost ad method of transitioning to v6. All stakeholders should be involved in negotiations, and the benefits/negatives carefully weighed.
Next you’ll need to audit existing infrastructure to see what needs updating and what can already handle the job.
“This would include a list of all infrastructure IPv4 addresses in the network, a list of where they are referred to within all applications, and a list of all DNS mappings. This assessment would verify if the current external DNS provider supports IPv6 and if the infrastructure devices supports IPv6,” they note.
Identifying the dead wood
“All applications and infrastructure devices that do not support IPv6 should be documented,” Network World continues.
“The process and cost required to upgrade them to support IPv6 should be documented and presented to management. A decision should be made on whether these devices and applications should be immediately upgraded to support IPv6. This is a critical step to make in defining scope of an IPv6 migration.”
Plans for migration
Once the analysis is complete a detailed plan of how and when migration should occur needs to be outlined.
It involves the critical decision about moving to co-existence or whether a full IPv6 transition makes more sense for your organisation based on cost, customer impact, hardware requirements and more.
Dual stacking typically allows organisations the freedom to continue operations while transitioning to IPv6.
However enterprise should make no mistake, time is of the essence. In the end the transition to IPv6 will proceed, ready or not. And if you’re not properly prepared your business runs the very real risk of lost communication, lost revenue and lost clientele.