- Software licenses are inflexible and inhibit the dynamic nature of SDN and private cloud deployments.
- Networking vendors should be developing new software licensing schemes to support the dynamism of a virtual data center.
One aspect of SDN and private clouds that does not get much discussion, but will be as much of a hurdle as any technical issue, is licensing. The problem has many dimensions, but they all boil down to a single point: software licenses are inflexible. A software license entitles you to use a product in a specific manner, but many of the licensing schemes in use are not flexible enough to really support the dynamism of an SDN or a private cloud. I believe this, more than anything, will inhibit the growth of SDN, because a rigid license conflicts with dynamic demands.
When an enterprise licenses a product, it pays a onetime fee to purchase a perpetual license or it pays a monthly recurring charge (MRC) for the product. The customer can use as many instances of the product as it is entitled via the license. Licenses get more complex when there are license tiers used to enable additional features, which often creates deficiencies that extend to subsequent feature licenses. For example, if you buy an application delivery controller that is licensed for 5,000 concurrent connections and you want to add a license for a firewall, you also need to buy a license for 5,000 connections as well. If your ADC is hardware-based and your infrastructure is relatively static, then you only need to buy the capacity you need and pay to increase it as needed.
SDN and virtual data centers are not static though. They are dynamic, and when you want to deploy a new application, you not only have to make sure you have sufficient compute, storage, and networking capacity; you also have to ensure that you have enough entitlements before the fact for any network services such as an ADC that you want to deploy. Do you need to scale up an application’s ADC or firewall to meet peak demand but you don’t have enough entitlements for one of the components? You’re out of luck, because no vendor or VAR is set up to support dynamic entitlements.
Note that network services on Amazon Web Services acquired through the Amazon Marketplace can be purchased on demand for periods as short as one hour, so dynamic licensing is possible if the proper entitlement infrastructure is in place.
I think vendors can address these licensing shortcoming in a few ways:
- Simplify the entitlement model so that all of the product features are available as a single purchase. If the entitlements are based on concurrent connections, then the license should cover all features at that capacity.
- Create a way to support dynamic entitlements that meet the needs of customers and are automated.
- Create a way to distribute a single license across many instances of a product so that entitlements can be used as a pool (versus per instance).
- Restructure entitlements into blocks of capacity over time and offer enterprises a realistic consumption-based model.
Being flexible with licensing will encourage enterprises to adopt SDN and private cloud strategies in the data center and increase the enterprise potential for this technology by removing concerns over excessive and ongoing licensing fees.