Posted by Michael Disabato
When I was in engineering school and working as an intern, I was introduced to the term "blivet." According to Wikipedia (http://en.wikipedia.org/wiki/Blivit), "In traditional U.S. Army slang dating back to the Second World War, a blivet was defined as "ten pounds of manure in a five pound bag" (a proverbial description of anything egregiously ugly or unmanageable); it was applied to an unmanageable situation, a crucial but substandard or damaged tool, or a self-important person." What does this have to do with networking and IPv6? Everything.
I have recently held discussions with several governmental organizations, retail, medical, and financial firms about IPv6 and whether or not they should proceed with it. In every case there has been interest, but no movement, mostly citing lack of business case. Well, I have one for you.
Several of these firms are exhausting the private IP space they are using. One of them had this happen overnight as they absorbed one of their former competitors, which had a network almost as big as theirs. One firm is close to hitting limits because they are virtualizing their desktops, and I don't mean thin clients accessing instances of Windows on a central machine. I mean multiple instances of multiple operating systems on their workstations. Each of these requires an IP address, so you can see where this is going. We may be looking at public IPv4 address exhaustion in one or two years, but some firms see it now. They have a 5 pound network with 10 pounds of addresses. Blivet.
One practice to alleviate this problem is using "dark" IP addresses. Basically you take a range of addresses assigned to another registry and treat them as unroutable, hiding them behind your firewall. This is all well and good until you either acquire the company that really owns the addresses and have to deal with overlapping address space or Something Goes Wrong with your firewall and this hidden address space becomes visible (oops). The latter can bring all sorts of collateral damage when news of this hits the press.
Another practice is to segment the network and create NAT areas. However, this can impact legacy applications, real-time applications (voice and video), and peer-to-peer applications.
What's the solution to this? Get a bigger bag. There is no longer time to wait on investigating and certifying IPv6 for use in the enterprise. Either a merger, acquisition, or virtualization of your infrastructure will force you to this before we run out of IPv4 addresses. The recommendations from Burton Group are:
- Set up a lab and begin testing and learning immediately
- Enable your edge connection to the Internet to handle IPv4 and IPv6
- Identify applications and infrastructure components that cannot be upgraded to hand IPv6 and make plans to isolate them in IPv4 islands with appropriate gateways.
- Set up dual stacks (IPv4 and IPv6) into your data center for you internal network
- Inventory your IP address space and keep a close watch on consumption rates
- Make sure all new applications can handle IPv4 and IPv6 and retrofit existing applications during maintenance cycles
Burton Group has documents that cover this in detail, and our consulting group can help you plan for the migration and adoption of IPv6. Tempus fugit, folks.
Michael