SDN is significantly improving the manageability and flexibility of the network. This includes automated traffic management, improved bandwidth engineering, and the ability to tailor the network “on demand” to customer needs. Today the large carriers are unable to offer customers truly flexible data networks, where customers can pay for only the bandwidth they use and automatically burst traffic as applications require. And, it is this bandwidth flexibility that could give carriers the edge they need to successfully deliver a range of cloud-based services.
Current hardware approaches force businesses to acquire standalone appliances per feature, resulting in costly, inflexible and slow solutions which end up having high OPEX.
Decoupling hardware and software network functions through NFV enables the provision of telco network services through COTS (Commodity Off the Shelf); standard box remotely configured and controlled by a central controller which executes network applications on demand.
Standard open SDN controllers will lead to a new scenario where hardware will be totally compatible between different providers ending any vendor-locking issues. This will also lead to a reduction in the number of devices; one server will be able to hold a series of network applications, thus having a much lower CAPEX associated with it.
One of the limitations of traditional network architectures is that applications running on L7 of the OSI model do not have visibility over the resources available on the network layer; therefore, resource provisioning is not efficient. Through SDN, developers could include software on the upper levels of the OSI (L7 / L4) to have control over the network on the lower layers (L2 / L3), thus generating added value.