...themselves offered few options other than outsourcing their public presence to obtain a public-facing presence.
The question is whether they will ever go back once IPv6 deployment is complete and addresses are available, or will those who do move to the cloud because they need a public-facing presence stay there, having invested in systems and architectures specific to addressing the challenges of a shared-resource environment?
Growth in service-layer virtualisation
For organisations that already have public IPv4 addresses, we will probably see an increase in the use of virtualisation — the same technology exploited by cloud and hosting providers to share those resources. Not the server or operating-system virtualisation that comes to mind most often when the technology is mentioned, but the service-layer virtualisation that has existed since the early days of network-address translation and load-balancing as a means to achieve scalability.
Most large organisations already employ service virtualisation — the practice of enabling multiple virtual-service hosts on the same IP address and port combination — and are using network-hosted technology such as load-balancers and application-delivery controllers to steer the traffic to the appropriate service host.
The impact of the dwindling supply of IPv4 addresses will be directly related to the length of time between depletion and full deployment of IPv6. It is in that interim period that we will see whether cloud computing can really follow through on the touted benefits of shared resources.
There is unlikely to be again a situation in which such a valuable resource will be in such short supply. Whether cloud computing or hosting providers will benefit depends largely on whether the perceived risks of cloud computing outweigh the benefits.
Of course, the rest of the industry might shift into high gear to deploy IPv6 and avoid the problem altogether. But given the scale of that switch, it is a possibility that unfortunately seems a lot less likely.
Lori MacVittie is responsible for application services education and evangelism at application delivery firm F5 Networks. Her role includes producing technical materials and participating in community-based forums and industry standards organisations. MacVittie has extensive programming experience as an application architect, as well as in network and systems development and administration.